spring-cloud-contract/1.1.x/spring-cloud-contract.xml

<?xml version="1.0" encoding="UTF-8"?>
<?asciidoc-toc maxdepth="3"?>
<?asciidoc-numbered?>
<book xmlns="http://docbook.org/ns/docbook" xmlns:xl="http://www.w3.org/1999/xlink" version="5.0" xml:lang="en">
<info>
<title>Spring Cloud Contract</title>
<date>2018-07-18</date>
</info>
<preface>
<title></title>
<simpara><emphasis>Documentation Authors: Adam Dudczak, Mathias Düsterhöft, Marcin Grzejszczak, Dennis Kieselhorst, Jakub Kubryński, Karol Lassak,
Olga Maciaszek-Sharma, Mariusz Smykuła, Dave Syer</emphasis></simpara>
<simpara>1.1.6.BUILD-SNAPSHOT</simpara>
</preface>
<chapter xml:id="_spring_cloud_contract">
<title>Spring Cloud Contract</title>
<simpara>What you always need is confidence in pushing new features into a new application or service in a distributed system.
This project provides support for Consumer Driven Contracts and service schemas in Spring applications, covering a
range of options for writing tests, publishing them as assets, asserting that a contract is kept by producers
and consumers, for HTTP and message-based interactions.</simpara>
</chapter>
<chapter xml:id="_spring_cloud_contract_verifier_introduction">
<title>Spring Cloud Contract Verifier Introduction</title>
<tip>
<simpara>The Accurest project was initially started by Marcin Grzejszczak and Jakub Kubrynski (<link xl:href="http://codearte.io">codearte.io</link>)</simpara>
</tip>
<simpara>Just to make long story short - Spring Cloud Contract Verifier is a tool that enables Consumer Driven Contract (CDC) development of JVM-based applications. It is shipped
with <emphasis>Contract Definition Language</emphasis> (DSL). Contract definitions are used to produce following resources:</simpara>
<itemizedlist>
<listitem>
<simpara>JSON stub definitions to be used by WireMock when doing integration testing on the client code (<emphasis>client tests</emphasis>).
Test code must still be written by hand, test data is produced by Spring Cloud Contract Verifier.</simpara>
</listitem>
<listitem>
<simpara>Messaging routes if you&#8217;re using one. We&#8217;re integrating with Spring Integration, Spring Cloud Stream, Spring AMQP and Apache Camel. You can however set your own integrations if you want to</simpara>
</listitem>
<listitem>
<simpara>Acceptance tests (in JUnit or Spock) used to verify if server-side implementation of the API is compliant with the contract (<emphasis>server tests</emphasis>).
Full test is generated by Spring Cloud Contract Verifier.</simpara>
</listitem>
</itemizedlist>
<simpara>Spring Cloud Contract Verifier moves TDD to the level of software architecture.</simpara>
<section xml:id="_why">
<title>Why?</title>
<simpara>Let us assume that we have a system comprising of multiple microservices:</simpara>
<informalfigure>
<mediaobject>
<imageobject>
<imagedata fileref="https://raw.githubusercontent.com/spring-cloud/spring-cloud-contract/1.0.x/docs/src/main/asciidoc/images/Deps.png"/>
</imageobject>
<textobject><phrase>Microservices Architecture</phrase></textobject>
</mediaobject>
</informalfigure>
<section xml:id="_testing_issues">
<title>Testing issues</title>
<simpara>If we wanted to test the application in top left corner if it can communicate with other services then we could do one of two things:</simpara>
<itemizedlist>
<listitem>
<simpara>deploy all microservices and perform end to end tests</simpara>
</listitem>
<listitem>
<simpara>mock other microservices in unit / integration tests</simpara>
</listitem>
</itemizedlist>
<simpara>Both have their advantages but also a lot of disadvantages. Let&#8217;s focus on the latter.</simpara>
<simpara><emphasis role="strong">Deploy all microservices and perform end to end tests</emphasis></simpara>
<simpara>Advantages:</simpara>
<itemizedlist>
<listitem>
<simpara>simulates production</simpara>
</listitem>
<listitem>
<simpara>tests real communication between services</simpara>
</listitem>
</itemizedlist>
<simpara>Disadvantages:</simpara>
<itemizedlist>
<listitem>
<simpara>to test one microservice we would have to deploy 6 microservices, a couple of databases etc.</simpara>
</listitem>
<listitem>
<simpara>the environment where the tests would be conducted would be locked for a single suite of tests (i.e. nobody else would be able to run the tests in the meantime).</simpara>
</listitem>
<listitem>
<simpara>long to run</simpara>
</listitem>
<listitem>
<simpara>very late feedback</simpara>
</listitem>
<listitem>
<simpara>extremely hard to debug</simpara>
</listitem>
</itemizedlist>
<simpara><emphasis role="strong">Mock other microservices in unit / integration tests</emphasis></simpara>
<simpara>Advantages:</simpara>
<itemizedlist>
<listitem>
<simpara>very fast feedback</simpara>
</listitem>
<listitem>
<simpara>no infrastructure requirements</simpara>
</listitem>
</itemizedlist>
<simpara>Disadvantages:</simpara>
<itemizedlist>
<listitem>
<simpara>the implementor of the service creates stubs thus they might have nothing to do with the reality</simpara>
</listitem>
<listitem>
<simpara>you can go to production with passing tests and failing production</simpara>
</listitem>
</itemizedlist>
<simpara>To solve the aforementioned issues Spring Cloud Contract Verifier with Stub Runner were created. Their main idea is to give you very fast feedback, without the need
to set up the whole world of microservices. If you work on stubs then the only applications you need are those that your application is using directly.</simpara>
<informalfigure>
<mediaobject>
<imageobject>
<imagedata fileref="https://raw.githubusercontent.com/spring-cloud/spring-cloud-contract/1.0.x/docs/src/main/asciidoc/images/Stubs2.png"/>
</imageobject>
<textobject><phrase>Stubbed Services</phrase></textobject>
</mediaobject>
</informalfigure>
<simpara>Spring Cloud Contract Verifier gives you the certainty that the stubs that you&#8217;re using were created by the service that you&#8217;re calling. Also if you can use them it means that they were
tested against the producer&#8217;s side. In other words - you can trust those stubs.</simpara>
</section>
</section>
<section xml:id="_purposes">
<title>Purposes</title>
<simpara>The main purposes of Spring Cloud Contract Verifier with Stub Runner are:</simpara>
<itemizedlist>
<listitem>
<simpara>to ensure that WireMock / Messaging stubs (used when developing the client) are doing exactly what actual server-side implementation will do,</simpara>
</listitem>
<listitem>
<simpara>to promote ATDD method and Microservices architectural style,</simpara>
</listitem>
<listitem>
<simpara>to provide a way to publish changes in contracts that are immediately visible on both sides,</simpara>
</listitem>
<listitem>
<simpara>to generate boilerplate test code used on the server side.</simpara>
</listitem>
</itemizedlist>
<important>
<simpara>Spring Cloud Contract Verifier&#8217;s purpose is NOT to start writing business features in the contracts.
Let&#8217;s assume that we have a business use case of fraud check. If a user can be a fraud for 100 different reasons,
we would assume that you would create 2 contracts. One for the positive and one for the negative fraud case.
Contract tests are used to test contracts between applications and not to simulate full behaviour.</simpara>
</important>
</section>
<section xml:id="_how">
<title>How</title>
<section xml:id="_define_the_contract">
<title>Define the contract</title>
<simpara>As consumers we need to define what exactly we want to achieve. We need to formulate our expectations. That&#8217;s why we write the following contract.</simpara>
<simpara>Let’s assume that we’d like to send the request containing the id of the client and the amount he wants to borrow from us. We’d like to send it to the /fraudcheck url via the PUT method.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package contracts

org.springframework.cloud.contract.spec.Contract.make {
	request { // (1)
		method 'PUT' // (2)
		url '/fraudcheck' // (3)
		body([ // (4)
			   "client.id": $(regex('[0-9]{10}')),
			   loanAmount: 99999
		])
		headers { // (5)
			contentType('application/json')
		}
	}
	response { // (6)
		status OK() // (7)
		body([ // (8)
			   fraudCheckStatus: "FRAUD",
			   "rejection.reason": "Amount too high"
		])
		headers { // (9)
			contentType('application/json')
		}
	}
}

/*
From the Consumer perspective, when shooting a request in the integration test:

(1) - If the consumer sends a request
(2) - With the "PUT" method
(3) - to the URL "/fraudcheck"
(4) - with the JSON body that
 * has a field `client.id` that matches a regular expression `[0-9]{10}`
 * has a field `loanAmount` that is equal to `99999`
(5) - with header `Content-Type` equal to `application/json`
(6) - then the response will be sent with
(7) - status equal `200`
(8) - and JSON body equal to
 { "fraudCheckStatus": "FRAUD", "rejectionReason": "Amount too high" }
(9) - with header `Content-Type` equal to `application/json`

From the Producer perspective, in the autogenerated producer-side test:

(1) - A request will be sent to the producer
(2) - With the "PUT" method
(3) - to the URL "/fraudcheck"
(4) - with the JSON body that
 * has a field `client.id` that will have a generated value that matches a regular expression `[0-9]{10}`
 * has a field `loanAmount` that is equal to `99999`
(5) - with header `Content-Type` equal to `application/json`
(6) - then the test will assert if the response has been sent with
(7) - status equal `200`
(8) - and JSON body equal to
 { "fraudCheckStatus": "FRAUD", "rejectionReason": "Amount too high" }
(9) - with header `Content-Type` matching `application/json.*`
 */</programlisting>
</section>
<section xml:id="_client_side">
<title>Client Side</title>
<simpara>Spring Cloud Contract will generate stubs, which you can use during client side testing.
You will have a WireMock instance / Messaging route up and running that simulates the service Y.
You would like to feed that instance with a proper stub definition.</simpara>
<simpara>At some point in time you need to send a request to the Fraud Detection service.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">ResponseEntity&lt;FraudServiceResponse&gt; response =
		restTemplate.exchange("http://localhost:" + port + "/fraudcheck", HttpMethod.PUT,
				new HttpEntity&lt;&gt;(request, httpHeaders),
				FraudServiceResponse.class);</programlisting>
<simpara>Annotate your test class with <literal>@AutoConfigureStubRunner</literal>. In the annotation provide the group id and artifact id for the Stub Runner to download stubs of your collaborators.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment=WebEnvironment.NONE)
@AutoConfigureStubRunner(ids = {"com.example:http-server-dsl:+:stubs:6565"},
		stubsMode = StubRunnerProperties.StubsMode.LOCAL)
@DirtiesContext
public class LoanApplicationServiceTests {</programlisting>
<simpara>After that, during the tests Spring Cloud Contract will automatically find the stubs (simulating the real service) in Maven repository and expose them on configured (or random) port.</simpara>
</section>
<section xml:id="_server_side">
<title>Server Side</title>
<simpara>Being a service Y since you are developing your stub, you need to be sure that it&#8217;s actually resembling your
concrete implementation. You can&#8217;t have a situation where your stub acts in one way and your application on
production behaves in a different way.</simpara>
<simpara>That&#8217;s why from the provided stub acceptance tests will be generated that will ensure
that your application behaves in the same way as you define in your stub.</simpara>
<simpara>The autogenerated test would look like this:</simpara>
<programlisting language="java" linenumbering="unnumbered">@Test
public void validate_shouldMarkClientAsFraud() throws Exception {
    // given:
        MockMvcRequestSpecification request = given()
                .header("Content-Type", "application/vnd.fraud.v1+json")
                .body("{\"client.id\":\"1234567890\",\"loanAmount\":99999}");

    // when:
        ResponseOptions response = given().spec(request)
                .put("/fraudcheck");

    // then:
        assertThat(response.statusCode()).isEqualTo(200);
        assertThat(response.header("Content-Type")).matches("application/vnd.fraud.v1.json.*");
    // and:
        DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
        assertThatJson(parsedJson).field("['fraudCheckStatus']").matches("[A-Z]{5}");
        assertThatJson(parsedJson).field("['rejection.reason']").isEqualTo("Amount too high");
}</programlisting>
</section>
</section>
<section xml:id="_step_by_step_guide_to_cdc">
<title>Step by step guide to CDC</title>
<simpara>Let&#8217;s take an example of Fraud Detection and Loan Issuance process. The business scenario is such that we want to issue loans to people but don&#8217;t want them to steal the money from us. The current implementation of our system grants loans to everybody.</simpara>
<simpara>Let&#8217;s assume that the <literal>Loan Issuance</literal> is a client to the
<literal>Fraud Detection</literal> server. In the current sprint we are required to develop a new feature - if a client wants to borrow too much money then we mark him as fraud.</simpara>
<simpara>Technical remark - Fraud Detection will have artifact id <literal>http-server</literal>, Loan Issuance <literal>http-client</literal> and both have group id <literal>com.example</literal>.</simpara>
<simpara>Social remark - both client and server development teams need to communicate directly and discuss changes while
going through the process. CDC is all about communication.</simpara>
<simpara>The <link xl:href="https://github.com/spring-cloud/spring-cloud-contract/tree/1.0.x/samples/standalone/dsl/http-server">server side code is available here</link> and <link xl:href="https://github.com/spring-cloud/spring-cloud-contract/tree/1.0.x/samples/standalone/dsl/http-client">the client side code here</link>.</simpara>
<tip>
<simpara>In this case the ownership of the contracts lays on the producer side. It means that physically
all the contract are present in the producer&#8217;s repository</simpara>
</tip>
<section xml:id="_technical_note">
<title>Technical note</title>
<simpara>If using the <emphasis role="strong">SNAPSHOT</emphasis> / <emphasis role="strong">Milestone</emphasis> / <emphasis role="strong">Release Candidate</emphasis> versions please add the following section to your</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;repositories&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-snapshots&lt;/id&gt;
		&lt;name&gt;Spring Snapshots&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/snapshot&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;true&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-milestones&lt;/id&gt;
		&lt;name&gt;Spring Milestones&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/milestone&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-releases&lt;/id&gt;
		&lt;name&gt;Spring Releases&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/release&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
&lt;/repositories&gt;
&lt;pluginRepositories&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-snapshots&lt;/id&gt;
		&lt;name&gt;Spring Snapshots&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/snapshot&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;true&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-milestones&lt;/id&gt;
		&lt;name&gt;Spring Milestones&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/milestone&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-releases&lt;/id&gt;
		&lt;name&gt;Spring Releases&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/release&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
&lt;/pluginRepositories&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">repositories {
	mavenCentral()
	mavenLocal()
	maven { url "https://repo.spring.io/snapshot" }
	maven { url "https://repo.spring.io/milestone" }
	maven { url "https://repo.spring.io/release" }
}</programlisting>
</para>
</formalpara>
</section>
<section xml:id="_consumer_side_loan_issuance">
<title>Consumer side (Loan Issuance)</title>
<simpara>As a developer of the Loan Issuance service (a consumer of the Fraud Detection server):</simpara>
<simpara><emphasis role="strong">start doing TDD by writing a test to your feature</emphasis></simpara>
<programlisting language="groovy" linenumbering="unnumbered">@Test
public void shouldBeRejectedDueToAbnormalLoanAmount() {
	// given:
	LoanApplication application = new LoanApplication(new Client("1234567890"),
			99999);
	// when:
	LoanApplicationResult loanApplication = service.loanApplication(application);
	// then:
	assertThat(loanApplication.getLoanApplicationStatus())
			.isEqualTo(LoanApplicationStatus.LOAN_APPLICATION_REJECTED);
	assertThat(loanApplication.getRejectionReason()).isEqualTo("Amount too high");
}</programlisting>
<simpara>We&#8217;ve just written a test of our new feature. If a loan application for a big amount is received we should reject that loan application with some description.</simpara>
<simpara><emphasis role="strong">write the missing implementation</emphasis></simpara>
<simpara>At some point in time you need to send a request to the Fraud Detection service. Let&#8217;s assume that we&#8217;d like to send the request containing the id of the client and the amount he wants to borrow from us. We&#8217;d like to send it to the <literal>/fraudcheck</literal> url via the <literal>PUT</literal> method.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">ResponseEntity&lt;FraudServiceResponse&gt; response =
		restTemplate.exchange("http://localhost:" + port + "/fraudcheck", HttpMethod.PUT,
				new HttpEntity&lt;&gt;(request, httpHeaders),
				FraudServiceResponse.class);</programlisting>
<simpara>For simplicity we&#8217;ve hardcoded the port of the Fraud Detection service at <literal>8080</literal> and our application is running on <literal>8090</literal>.</simpara>
<simpara>If we&#8217;d start the written test it would obviously break since we have no service running on port <literal>8080</literal>.</simpara>
<simpara><emphasis role="strong">clone the Fraud Detection service repository locally</emphasis></simpara>
<simpara>We&#8217;ll start playing around with the server side contract. That&#8217;s why we need to first clone it.</simpara>
<programlisting language="bash" linenumbering="unnumbered">git clone https://your-git-server.com/server-side.git local-http-server-repo</programlisting>
<simpara><emphasis role="strong">define the contract locally in the repo of Fraud Detection service</emphasis></simpara>
<simpara>As consumers we need to define what exactly we want to achieve. We need to formulate our expectations. That&#8217;s why we write the following contract.</simpara>
<important>
<simpara>We&#8217;re placing the contract under <literal>src/test/resources/contracts/fraud</literal> folder. The <literal>fraud</literal> folder
is important cause we&#8217;ll reference that folder in the producer&#8217;s test base class name.</simpara>
</important>
<programlisting language="groovy" linenumbering="unnumbered">package contracts

org.springframework.cloud.contract.spec.Contract.make {
	request { // (1)
		method 'PUT' // (2)
		url '/fraudcheck' // (3)
		body([ // (4)
			   "client.id": $(regex('[0-9]{10}')),
			   loanAmount: 99999
		])
		headers { // (5)
			contentType('application/json')
		}
	}
	response { // (6)
		status OK() // (7)
		body([ // (8)
			   fraudCheckStatus: "FRAUD",
			   "rejection.reason": "Amount too high"
		])
		headers { // (9)
			contentType('application/json')
		}
	}
}

/*
From the Consumer perspective, when shooting a request in the integration test:

(1) - If the consumer sends a request
(2) - With the "PUT" method
(3) - to the URL "/fraudcheck"
(4) - with the JSON body that
 * has a field `client.id` that matches a regular expression `[0-9]{10}`
 * has a field `loanAmount` that is equal to `99999`
(5) - with header `Content-Type` equal to `application/json`
(6) - then the response will be sent with
(7) - status equal `200`
(8) - and JSON body equal to
 { "fraudCheckStatus": "FRAUD", "rejectionReason": "Amount too high" }
(9) - with header `Content-Type` equal to `application/json`

From the Producer perspective, in the autogenerated producer-side test:

(1) - A request will be sent to the producer
(2) - With the "PUT" method
(3) - to the URL "/fraudcheck"
(4) - with the JSON body that
 * has a field `client.id` that will have a generated value that matches a regular expression `[0-9]{10}`
 * has a field `loanAmount` that is equal to `99999`
(5) - with header `Content-Type` equal to `application/json`
(6) - then the test will assert if the response has been sent with
(7) - status equal `200`
(8) - and JSON body equal to
 { "fraudCheckStatus": "FRAUD", "rejectionReason": "Amount too high" }
(9) - with header `Content-Type` matching `application/json.*`
 */</programlisting>
<simpara>The Contract is written using a statically typed Groovy DSL. You might be wondering what are those
<literal>value(client(&#8230;&#8203;), server(&#8230;&#8203;))</literal> parts. By using this notation Spring Cloud Contract allows you to
define parts of a JSON / URL / etc. which are dynamic. In case of an identifier or a timestamp you
don&#8217;t want to hardcode a value. You want to allow some different ranges of values. That&#8217;s why for
the consumer side you can set regular expressions matching those values. You can provide the body
either by means of a map notation or String with interpolations.
<link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract.html#_contract_dsl">Consult the docs
for more information.</link> We highly recommend using the map notation!</simpara>
<tip>
<simpara>It&#8217;s really important that you understand the map notation to set up contracts. Please read the
<link xl:href="http://groovy-lang.org/json.html">Groovy docs regarding JSON</link></simpara>
</tip>
<simpara>The aforementioned contract is an agreement between two sides that:</simpara>
<itemizedlist>
<listitem>
<simpara>if an HTTP request is sent with</simpara>
<itemizedlist>
<listitem>
<simpara>a method <literal>PUT</literal> on an endpoint <literal>/fraudcheck</literal></simpara>
</listitem>
<listitem>
<simpara>JSON body with <literal>client.id</literal> matching the regular expression <literal>[0-9]{10}</literal> and <literal>loanAmount</literal> equal to <literal>99999</literal></simpara>
</listitem>
<listitem>
<simpara>and with a header <literal>Content-Type</literal> equal to <literal>application/vnd.fraud.v1+json</literal></simpara>
</listitem>
</itemizedlist>
</listitem>
<listitem>
<simpara>then an HTTP response would be sent to the consumer that</simpara>
<itemizedlist>
<listitem>
<simpara>has status <literal>200</literal></simpara>
</listitem>
<listitem>
<simpara>contains JSON body with the <literal>fraudCheckStatus</literal> field containing a value <literal>FRAUD</literal> and the <literal>rejectionReason</literal> field having value <literal>Amount too high</literal></simpara>
</listitem>
<listitem>
<simpara>and a <literal>Content-Type</literal> header with a value of <literal>application/vnd.fraud.v1+json</literal></simpara>
</listitem>
</itemizedlist>
</listitem>
</itemizedlist>
<simpara>Once we&#8217;re ready to check the API in practice in the integration tests we need to just install the stubs locally</simpara>
<simpara><emphasis role="strong">add the Spring Cloud Contract Verifier plugin</emphasis></simpara>
<simpara>We can add either Maven or Gradle plugin - in this example we&#8217;ll show how to add Maven. First we need to add the <literal>Spring Cloud Contract</literal> BOM.</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependencyManagement&gt;
	&lt;dependencies&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
			&lt;artifactId&gt;spring-cloud-dependencies&lt;/artifactId&gt;
			&lt;version&gt;${spring-cloud-dependencies.version}&lt;/version&gt;
			&lt;type&gt;pom&lt;/type&gt;
			&lt;scope&gt;import&lt;/scope&gt;
		&lt;/dependency&gt;
	&lt;/dependencies&gt;
&lt;/dependencyManagement&gt;</programlisting>
<simpara>Next, the <literal>Spring Cloud Contract Verifier</literal> Maven plugin</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
	&lt;extensions&gt;true&lt;/extensions&gt;
	&lt;configuration&gt;
		&lt;packageWithBaseClasses&gt;com.example.fraud&lt;/packageWithBaseClasses&gt;
	&lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
<simpara>Since the plugin was added we get the <literal>Spring Cloud Contract Verifier</literal> features which from the provided contracts:</simpara>
<itemizedlist>
<listitem>
<simpara>generate and run tests</simpara>
</listitem>
<listitem>
<simpara>produce and install stubs</simpara>
</listitem>
</itemizedlist>
<simpara>We don&#8217;t want to generate tests since we, as consumers, want only to play with the stubs. That&#8217;s why we need to skip the tests generation and execution. When we execute:</simpara>
<programlisting language="bash" linenumbering="unnumbered">cd local-http-server-repo
./mvnw clean install -DskipTests</programlisting>
<simpara>In the logs we&#8217;ll see something like this:</simpara>
<programlisting language="bash" linenumbering="unnumbered">[INFO] --- spring-cloud-contract-maven-plugin:1.0.0.BUILD-SNAPSHOT:generateStubs (default-generateStubs) @ http-server ---
[INFO] Building jar: /some/path/http-server/target/http-server-0.0.1-SNAPSHOT-stubs.jar
[INFO]
[INFO] --- maven-jar-plugin:2.6:jar (default-jar) @ http-server ---
[INFO] Building jar: /some/path/http-server/target/http-server-0.0.1-SNAPSHOT.jar
[INFO]
[INFO] --- spring-boot-maven-plugin:1.5.4.BUILD-SNAPSHOT:repackage (default) @ http-server ---
[INFO]
[INFO] --- maven-install-plugin:2.5.2:install (default-install) @ http-server ---
[INFO] Installing /some/path/http-server/target/http-server-0.0.1-SNAPSHOT.jar to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT.jar
[INFO] Installing /some/path/http-server/pom.xml to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT.pom
[INFO] Installing /some/path/http-server/target/http-server-0.0.1-SNAPSHOT-stubs.jar to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT-stubs.jar</programlisting>
<simpara>This line is extremely important</simpara>
<programlisting language="bash" linenumbering="unnumbered">[INFO] Installing /some/path/http-server/target/http-server-0.0.1-SNAPSHOT-stubs.jar to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT-stubs.jar</programlisting>
<simpara>It&#8217;s confirming that the stubs of the <literal>http-server</literal> have been installed in the local repository.</simpara>
<simpara><emphasis role="strong">run the integration tests</emphasis></simpara>
<simpara>In order to profit from the Spring Cloud Contract Stub Runner functionality of automatic stub downloading you have to do the following in our consumer side project (<literal>Loan Application service</literal>).</simpara>
<simpara>Add the <literal>Spring Cloud Contract</literal> BOM</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependencyManagement&gt;
	&lt;dependencies&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
			&lt;artifactId&gt;spring-cloud-dependencies&lt;/artifactId&gt;
			&lt;version&gt;${spring-cloud-dependencies.version}&lt;/version&gt;
			&lt;type&gt;pom&lt;/type&gt;
			&lt;scope&gt;import&lt;/scope&gt;
		&lt;/dependency&gt;
	&lt;/dependencies&gt;
&lt;/dependencyManagement&gt;</programlisting>
<simpara>Add the dependency to <literal>Spring Cloud Contract Stub Runner</literal></simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-starter-contract-stub-runner&lt;/artifactId&gt;
	&lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;</programlisting>
<simpara>Annotate your test class with <literal>@AutoConfigureStubRunner</literal>. In the annotation provide the group id and artifact id for the Stub Runner to download stubs of your collaborators. Also provide the offline work switch since you&#8217;re playing with the collaborators offline (optional step).</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment=WebEnvironment.NONE)
@AutoConfigureStubRunner(ids = {"com.example:http-server-dsl:+:stubs:6565"},
		stubsMode = StubRunnerProperties.StubsMode.LOCAL)
@DirtiesContext
public class LoanApplicationServiceTests {</programlisting>
<simpara>Now if you run your tests you&#8217;ll see sth like this:</simpara>
<programlisting language="bash" linenumbering="unnumbered">2016-07-19 14:22:25.403  INFO 41050 --- [           main] o.s.c.c.stubrunner.AetherStubDownloader  : Desired version is + - will try to resolve the latest version
2016-07-19 14:22:25.438  INFO 41050 --- [           main] o.s.c.c.stubrunner.AetherStubDownloader  : Resolved version is 0.0.1-SNAPSHOT
2016-07-19 14:22:25.439  INFO 41050 --- [           main] o.s.c.c.stubrunner.AetherStubDownloader  : Resolving artifact com.example:http-server:jar:stubs:0.0.1-SNAPSHOT using remote repositories []
2016-07-19 14:22:25.451  INFO 41050 --- [           main] o.s.c.c.stubrunner.AetherStubDownloader  : Resolved artifact com.example:http-server:jar:stubs:0.0.1-SNAPSHOT to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT-stubs.jar
2016-07-19 14:22:25.465  INFO 41050 --- [           main] o.s.c.c.stubrunner.AetherStubDownloader  : Unpacking stub from JAR [URI: file:/path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT-stubs.jar]
2016-07-19 14:22:25.475  INFO 41050 --- [           main] o.s.c.c.stubrunner.AetherStubDownloader  : Unpacked file to [/var/folders/0p/xwq47sq106x1_g3dtv6qfm940000gq/T/contracts100276532569594265]
2016-07-19 14:22:27.737  INFO 41050 --- [           main] o.s.c.c.stubrunner.StubRunnerExecutor    : All stubs are now running RunningStubs [namesAndPorts={com.example:http-server:0.0.1-SNAPSHOT:stubs=8080}]</programlisting>
<simpara>Which means that Stub Runner has found your stubs and started a server for app with group id <literal>com.example</literal>, artifact id <literal>http-server</literal> with version <literal>0.0.1-SNAPSHOT</literal> of the stubs and with <literal>stubs</literal> classifier on port <literal>8080</literal>.</simpara>
<simpara><emphasis role="strong">file a PR</emphasis></simpara>
<simpara>What we did until now is an iterative process. We can play around with the contract, install it locally and work on the consumer side until we&#8217;re happy with the contract.</simpara>
<simpara>Once we&#8217;re satisfied with the results and the test passes publish a PR to the server side. Currently the consumer side work is done.</simpara>
</section>
<section xml:id="_producer_side_fraud_detection_server">
<title>Producer side (Fraud Detection server)</title>
<simpara>As a developer of the Fraud Detection server (a server to the Loan Issuance service):</simpara>
<simpara><emphasis role="strong">initial implementation</emphasis></simpara>
<simpara>As a reminder here you can see the initial implementation</simpara>
<programlisting language="java" linenumbering="unnumbered">@RequestMapping(value = "/fraudcheck", method = PUT)
public FraudCheckResult fraudCheck(@RequestBody FraudCheck fraudCheck) {
return new FraudCheckResult(FraudCheckStatus.OK, NO_REASON);
}</programlisting>
<simpara><emphasis role="strong">take over the PR</emphasis></simpara>
<programlisting language="bash" linenumbering="unnumbered">git checkout -b contract-change-pr master
git pull https://your-git-server.com/server-side-fork.git contract-change-pr</programlisting>
<simpara>You have to add the dependencies needed by the autogenerated tests</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-starter-contract-verifier&lt;/artifactId&gt;
	&lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;</programlisting>
<simpara>In the configuration of the Maven plugin we passed the <literal>packageWithBaseClasses</literal> property</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
	&lt;extensions&gt;true&lt;/extensions&gt;
	&lt;configuration&gt;
		&lt;packageWithBaseClasses&gt;com.example.fraud&lt;/packageWithBaseClasses&gt;
	&lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
<important>
<simpara>We&#8217;ve decided to use the "convention based" naming by setting the <literal>packageWithBaseClasses</literal> property.
That means that 2 last packages will be combined into a name of the base test class. In our case the contracts
were placed under <literal>src/test/resources/contracts/fraud</literal>. Since we don&#8217;t have 2 packages starting from the <literal>contracts</literal>
folder we&#8217;re picking only one which is <literal>fraud</literal>. We&#8217;re adding the <literal>Base</literal> suffix and we&#8217;re capitalizing <literal>fraud</literal>.
That gives us the <literal>FraudBase</literal> test class name.</simpara>
</important>
<simpara>That&#8217;s because all the generated tests will extend that class. Over there you can set up your Spring Context or
whatever is necessary. In our case we&#8217;re using <link xl:href="http://rest-assured.io/">Rest Assured MVC</link> to start the server side <literal>FraudDetectionController</literal>.</simpara>
<programlisting language="java" linenumbering="unnumbered">package com.example.fraud;

import org.junit.Before;

import io.restassured.module.mockmvc.RestAssuredMockMvc;

public class FraudBase {
	@Before
	public void setup() {
		RestAssuredMockMvc.standaloneSetup(new FraudDetectionController(),
				new FraudStatsController(stubbedStatsProvider()));
	}

	private StatsProvider stubbedStatsProvider() {
		return fraudType -&gt; {
			switch (fraudType) {
			case DRUNKS:
				return 100;
			case ALL:
				return 200;
			}
			return 0;
		};
	}

	public void assertThatRejectionReasonIsNull(Object rejectionReason) {
		assert rejectionReason == null;
	}
}</programlisting>
<simpara>Now, if you run the <literal>./mvnw clean install</literal> you would get sth like this:</simpara>
<programlisting language="bash" linenumbering="unnumbered">Results :

Tests in error:
  ContractVerifierTest.validate_shouldMarkClientAsFraud:32 » IllegalState Parsed...</programlisting>
<simpara>That&#8217;s because you have a new contract from which a test was generated and it failed since you haven&#8217;t implemented the feature. The autogenerated test would look like this:</simpara>
<programlisting language="java" linenumbering="unnumbered">@Test
public void validate_shouldMarkClientAsFraud() throws Exception {
    // given:
        MockMvcRequestSpecification request = given()
                .header("Content-Type", "application/vnd.fraud.v1+json")
                .body("{\"client.id\":\"1234567890\",\"loanAmount\":99999}");

    // when:
        ResponseOptions response = given().spec(request)
                .put("/fraudcheck");

    // then:
        assertThat(response.statusCode()).isEqualTo(200);
        assertThat(response.header("Content-Type")).matches("application/vnd.fraud.v1.json.*");
    // and:
        DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
        assertThatJson(parsedJson).field("['fraudCheckStatus']").matches("[A-Z]{5}");
        assertThatJson(parsedJson).field("['rejection.reason']").isEqualTo("Amount too high");
}</programlisting>
<simpara>As you can see all the <literal>producer()</literal> parts of the Contract that were present in the <literal>value(consumer(&#8230;&#8203;), producer(&#8230;&#8203;))</literal> blocks got injected into the test.</simpara>
<simpara>What&#8217;s important here to note is that on the producer side we also are doing TDD. We have expectations in form of a test. This test is shooting a request to our own application to an URL, headers and body defined in the contract. It also is expecting very precisely defined values in the response. In other words you have is your <literal>red</literal> part of <literal>red</literal>, <literal>green</literal> and <literal>refactor</literal>. Time to convert the <literal>red</literal> into the <literal>green</literal>.</simpara>
<simpara><emphasis role="strong">write the missing implementation</emphasis></simpara>
<simpara>Now since we now what is the expected input and expected output let&#8217;s write the missing implementation.</simpara>
<programlisting language="java" linenumbering="unnumbered">@RequestMapping(value = "/fraudcheck", method = PUT)
public FraudCheckResult fraudCheck(@RequestBody FraudCheck fraudCheck) {
if (amountGreaterThanThreshold(fraudCheck)) {
	return new FraudCheckResult(FraudCheckStatus.FRAUD, AMOUNT_TOO_HIGH);
}
return new FraudCheckResult(FraudCheckStatus.OK, NO_REASON);
}</programlisting>
<simpara>If we execute <literal>./mvnw clean install</literal> again the tests will pass. Since the <literal>Spring Cloud Contract Verifier</literal> plugin adds the tests to the <literal>generated-test-sources</literal> you can actually run those tests from your IDE.</simpara>
<simpara><emphasis role="strong">deploy your app</emphasis></simpara>
<simpara>Once you&#8217;ve finished your work it&#8217;s time to deploy your change. First merge the branch</simpara>
<programlisting language="bash" linenumbering="unnumbered">git checkout master
git merge --no-ff contract-change-pr
git push origin master</programlisting>
<simpara>Then we assume that your CI would run sth like <literal>./mvnw clean deploy</literal> which would publish both the application and the stub artifcats.</simpara>
</section>
<section xml:id="_consumer_side_loan_issuance_final_step">
<title>Consumer side (Loan Issuance) final step</title>
<simpara>As a developer of the Loan Issuance service (a consumer of the Fraud Detection server):</simpara>
<simpara><emphasis role="strong">merge branch to master</emphasis></simpara>
<programlisting language="bash" linenumbering="unnumbered">git checkout master
git merge --no-ff contract-change-pr</programlisting>
<simpara><emphasis role="strong">work online</emphasis></simpara>
<simpara>Now you can disable the offline work for Spring Cloud Contract Stub Runner and provide where the repository with your stubs is placed. At this moment the stubs of the server side will be automatically downloaded from Nexus / Artifactory.
You can switch off the value of the <literal>workOffline</literal> parameter in your annotation. Below you can see an
example of achieving the same by changing the properties.</simpara>
<programlisting language="yaml" linenumbering="unnumbered">stubrunner:
  ids: 'com.example:http-server-dsl:+:stubs:8080'
  repositoryRoot: https://repo.spring.io/libs-snapshot</programlisting>
<simpara>And that&#8217;s it!</simpara>
</section>
</section>
<section xml:id="_dependencies">
<title>Dependencies</title>
<simpara>The best way to add the dependencies is to just use the proper <literal>starter</literal> dependency.</simpara>
<simpara>For <literal>stub-runner</literal> use <literal>spring-cloud-starter-stub-runner</literal> and when you&#8217;re using a plugin just add
<literal>spring-cloud-starter-contract-verifier</literal>.</simpara>
</section>
<section xml:id="_additional_links">
<title>Additional links</title>
<simpara>Below you can find some resources related to Spring Cloud Contract Verifier and Stub Runner. Note that some can be outdated since the Spring Cloud Contract Verifier project
is under constant development.</simpara>
<section xml:id="_spring_cloud_contract_video">
<title>Spring Cloud Contract video</title>
<simpara>You can check out the video from the Warsaw JUG about Spring Cloud Contract:</simpara>

</section>
<section xml:id="_readings">
<title>Readings</title>
<itemizedlist>
<listitem>
<simpara><link xl:href="https://www.slideshare.net/MarcinGrzejszczak/stick-to-the-rules-consumer-driven-contracts-201507-confitura">Slides from Marcin Grzejszczak&#8217;s talk about Accurest</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="http://toomuchcoding.com/blog/categories/accurest/">Accurest related articles from Marcin Grzejszczak&#8217;s blog</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="http://toomuchcoding.com/blog/categories/spring-cloud-contract/">Spring Cloud Contract related articles from Marcin Grzejszczak&#8217;s blog</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="http://groovy-lang.org/json.html">Groovy docs regarding JSON</link></simpara>
</listitem>
</itemizedlist>
</section>
</section>
<section xml:id="_samples">
<title>Samples</title>
<simpara>Here you can find some <link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples">samples</link>.</simpara>
</section>
</chapter>
<chapter xml:id="_spring_cloud_contract_verifier_setup">
<title>Spring Cloud Contract Verifier Setup</title>
<section xml:id="_gradle_project">
<title>Gradle Project</title>
<section xml:id="_prerequisites">
<title>Prerequisites</title>
<simpara>In order to use Spring Cloud Contract Verifier with WireMock you have to use Gradle or Maven plugin.</simpara>
<warning>
<simpara>If you want to use Spock in your projects you have to add separately
the <literal>spock-core</literal> and <literal>spock-spring</literal> modules. Check <link xl:href="https://spockframework.github.io/">Spock docs for more information</link></simpara>
</warning>
</section>
<section xml:id="_add_gradle_plugin_with_dependencies">
<title>Add gradle plugin with dependencies</title>
<programlisting language="groovy" linenumbering="unnumbered">buildscript {
	repositories {
		mavenCentral()
	}
	dependencies {
	    classpath "org.springframework.boot:spring-boot-gradle-plugin:${springboot_version}"
		classpath "org.springframework.cloud:spring-cloud-contract-gradle-plugin:${verifier_version}"
	}
}

apply plugin: 'groovy'
apply plugin: 'spring-cloud-contract'

dependencyManagement {
	imports {
		mavenBom "org.springframework.cloud:spring-cloud-contract-dependencies:${verifier_version}"
	}
}

dependencies {
	testCompile 'org.codehaus.groovy:groovy-all:2.4.6'
	// example with adding Spock core and Spock Spring
	testCompile 'org.spockframework:spock-core:1.0-groovy-2.4'
	testCompile 'org.spockframework:spock-spring:1.0-groovy-2.4'
	testCompile 'org.springframework.cloud:spring-cloud-starter-contract-verifier'
}</programlisting>
</section>
<section xml:id="_gradle_and_rest_assured_3_0">
<title>Gradle and Rest Assured 3.0</title>
<simpara>By default Rest Assured 2.x is added to the classpath. However in order to give the users the
opportunity to use Rest Assured 3.x it&#8217;s enough to add it to the plugins classpath.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">buildscript {
	repositories {
		mavenCentral()
	}
	dependencies {
	    classpath "org.springframework.boot:spring-boot-gradle-plugin:${springboot_version}"
		classpath "org.springframework.cloud:spring-cloud-contract-gradle-plugin:${verifier_version}"
		classpath "io.rest-assured:rest-assured:3.0.2"
		classpath "io.rest-assured:spring-mock-mvc:3.0.2"
	}
}

depenendencies {
    // all dependencies
    // you can exclude rest-assured from spring-cloud-contract-verifier
    testCompile "io.rest-assured:rest-assured:3.0.2"
    testCompile "io.rest-assured:spring-mock-mvc:3.0.2"
}</programlisting>
<simpara>That way the plugin will automatically see that Rest Assured 3.x is present on the classpath
and will modify the imports accordingly.</simpara>
</section>
<section xml:id="_snapshot_versions_for_gradle">
<title>Snapshot versions for Gradle</title>
<simpara>Add the additional snapshot repository to your build.gradle to use snapshot versions which are automatically uploaded after every successful build:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">buildscript {
	repositories {
		mavenCentral()
		mavenLocal()
		maven { url "https://repo.spring.io/snapshot" }
		maven { url "https://repo.spring.io/milestone" }
		maven { url "https://repo.spring.io/release" }
	}
}</programlisting>
</section>
<section xml:id="_add_stubs">
<title>Add stubs</title>
<simpara>By default Spring Cloud Contract Verifier is looking for stubs in <literal>src/test/resources/contracts</literal> directory.</simpara>
<simpara>Directory containing stub definitions is treated as a class name, and each stub definition is treated as a single test.
We assume that it contains at least one directory which will be used as test class name. If there is more than one level of nested directories all except the last one will be used as package name.
So with following structure</simpara>
<programlisting language="groovy" linenumbering="unnumbered">src/test/resources/contracts/myservice/shouldCreateUser.groovy
src/test/resources/contracts/myservice/shouldReturnUser.groovy</programlisting>
<simpara>Spring Cloud Contract Verifier will create test class <literal>defaultBasePackage.MyService</literal> with two methods</simpara>
<itemizedlist>
<listitem>
<simpara><literal>shouldCreateUser()</literal></simpara>
</listitem>
<listitem>
<simpara><literal>shouldReturnUser()</literal></simpara>
</listitem>
</itemizedlist>
</section>
<section xml:id="_run_plugin">
<title>Run plugin</title>
<simpara>Plugin registers itself to be invoked before <literal>check</literal> task. You have nothing to do as long as you want it to be part of your build process. If you just want to generate tests please invoke <literal>generateContractTests</literal> task.</simpara>
</section>
<section xml:id="_default_setup">
<title>Default setup</title>
<simpara>Default Gradle Plugin setup creates the following Gradle part of the build (it&#8217;s a pseudocode)</simpara>
<programlisting language="groovy" linenumbering="unnumbered">contracts {
    targetFramework = 'JUNIT'
    testMode = 'MockMvc'
    generatedTestSourcesDir = project.file("${project.buildDir}/generated-test-sources/contracts")
    contractsDslDir = "${project.rootDir}/src/test/resources/contracts"
    basePackageForTests = 'org.springframework.cloud.verifier.tests'
    stubsOutputDir = project.file("${project.buildDir}/stubs")

    // the following properties are used when you want to provide where the JAR with contract lays
    contractDependency {
        stringNotation = ''
    }
    contractsPath = ''
    contractsWorkOffline = false
    contractRepository {
        cacheDownloadedContracts(true)
    }
}

tasks.create(type: Jar, name: 'verifierStubsJar', dependsOn: 'generateClientStubs') {
    baseName = project.name
    classifier = contracts.stubsSuffix
    from contractVerifier.stubsOutputDir
}

project.artifacts {
    archives task
}

tasks.create(type: Copy, name: 'copyContracts') {
    from contracts.contractsDslDir
    into contracts.stubsOutputDir
}

verifierStubsJar.dependsOn 'copyContracts'

publishing {
    publications {
        stubs(MavenPublication) {
            artifactId project.name
            artifact verifierStubsJar
        }
    }
}</programlisting>
</section>
<section xml:id="_configure_plugin">
<title>Configure plugin</title>
<simpara>To change default configuration just add <literal>contracts</literal> snippet to your Gradle config</simpara>
<programlisting language="groovy" linenumbering="unnumbered">contracts {
	testMode = 'MockMvc'
	baseClassForTests = 'org.mycompany.tests'
	generatedTestSourcesDir = project.file('src/generatedContract')
}</programlisting>
</section>
<section xml:id="_configuration_options">
<title>Configuration options</title>
<itemizedlist>
<listitem>
<simpara><emphasis role="strong">testMode</emphasis> - defines mode for acceptance tests. By default MockMvc which is based on Spring&#8217;s MockMvc. It can also be changed to <emphasis role="strong">JaxRsClient</emphasis> or to <emphasis role="strong">Explicit</emphasis> for real HTTP calls.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">imports</emphasis> - array with imports that should be included in generated tests (for example ['org.myorg.Matchers']). By default empty array []</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">staticImports</emphasis> - array with static imports that should be included in generated tests(for example ['org.myorg.Matchers.*']). By default empty array []</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">basePackageForTests</emphasis> - specifies base package for all generated tests. By default set to org.springframework.cloud.verifier.tests</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">baseClassForTests</emphasis> - base class for all generated tests. By default <literal>spock.lang.Specification</literal> if using Spock tests.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">packageWithBaseClasses</emphasis> - instead of providing a fixed value for base class you can provide a package where all the base classes lay. Takes precedence over <emphasis role="strong">baseClassForTests</emphasis>.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">baseClassMappings</emphasis> - explicitly map contract package to a FQN of a base class. Takes precedence over <emphasis role="strong">packageWithBaseClasses</emphasis> and <emphasis role="strong">baseClassForTests</emphasis>.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">ruleClassForTests</emphasis> - specifies Rule which should be added to generated test classes.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">ignoredFiles</emphasis> - Ant matcher allowing defining stub files for which processing should be skipped. By default empty array []</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsDslDir</emphasis> - directory containing contracts written using the GroovyDSL. By default <literal>$rootDir/src/test/resources/contracts</literal></simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">generatedTestSourcesDir</emphasis> - test source directory where tests generated from Groovy DSL should be placed. By default <literal>$buildDir/generated-test-sources/contractVerifier</literal></simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">stubsOutputDir</emphasis> - dir where the generated WireMock stubs from Groovy DSL should be placed</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">targetFramework</emphasis> - the target test framework to be used; currently Spock and JUnit are supported with JUnit being the default framework</simpara>
</listitem>
</itemizedlist>
<simpara>The following properties are used when you want to provide where the JAR with contract lays</simpara>
<itemizedlist>
<listitem>
<simpara><emphasis role="strong">contractDependency</emphasis> - the Dependency that provides <literal>groupid:artifactid:version:classifier</literal> coordinates. You can use the <literal>contractDependency</literal> closure to set it up</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsPath</emphasis> - if contract deps are downloaded will default to <literal>groupid/artifactid</literal> where <literal>groupid</literal> will be slash separated. Otherwise will scan contracts under provided directory</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsWorkOffline</emphasis> - in order not to download the dependencies each time you can download them once and work offline afterwards (reuse local Maven repo)</simpara>
</listitem>
</itemizedlist>
</section>
<section xml:id="_single_base_class_for_all_tests">
<title>Single base class for all tests</title>
<simpara>When using Spring Cloud Contract Verifier in default MockMvc you need to create a base specification for all generated acceptance tests. In this class you need to point to endpoint which should be verified.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">abstract class BaseMockMvcSpec extends Specification {

	def setup() {
		RestAssuredMockMvc.standaloneSetup(new PairIdController())
	}

	void isProperCorrelationId(Integer correlationId) {
		assert correlationId == 123456
	}

	void isEmpty(String value) {
		assert value == null
	}

}</programlisting>
<simpara>In case of using <literal>Explicit</literal> mode, you can use base class to initialize the whole tested app similarly as in regular integration tests. In case of <literal>JAXRSCLIENT</literal> mode this base class
should also contain <literal>protected WebTarget webTarget</literal> field, right now the only option to test JAX-RS API is to start a web server.</simpara>
</section>
<section xml:id="_different_base_classes_for_contracts">
<title>Different base classes for contracts</title>
<simpara>If your base classes differ between contracts you can tell the Spring Cloud Contract plugin which class should get
extended by the autogenerated tests. You have two options:</simpara>
<itemizedlist>
<listitem>
<simpara>follow a convention by providing the <literal>packageWithBaseClasses</literal></simpara>
</listitem>
<listitem>
<simpara>provide explicit mapping via <literal>baseClassMappings</literal></simpara>
</listitem>
</itemizedlist>
<simpara><emphasis role="strong">Convention</emphasis></simpara>
<simpara>The convention is such that if you have a contract under e.g. <literal>src/test/resources/contract/foo/bar/baz/</literal> and provide the value of the <literal>packageWithBaseClasses</literal> property
to <literal>com.example.base</literal> then we will assume that there is a <literal>BarBazBase</literal> class under <literal>com.example.base</literal> package. In other words we take last two parts of package
if they exist and form a class with a <literal>Base</literal> suffix. Takes precedence over <emphasis role="strong">baseClassForTests</emphasis>. Example of usage in the <literal>contracts</literal> closure:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">packageWithBaseClasses = 'com.example.base'</programlisting>
<simpara><emphasis role="strong">Mapping</emphasis></simpara>
<simpara>You can manually map a regular expression of the contract&#8217;s package to fully qualified name of the base class for the matched contract.
Let&#8217;s take a look at the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">baseClassForTests = "com.example.FooBase"
baseClassMappings {
	baseClassMapping('.*/com/.*', 'com.example.ComBase')
	baseClassMapping('.*/bar/.*':'com.example.BarBase')
}</programlisting>
<simpara>Let&#8217;s assume that you have contracts under
 - <literal>src/test/resources/contract/com/</literal>
 - <literal>src/test/resources/contract/foo/</literal></simpara>
<simpara>By providing the <literal>baseClassForTests</literal> we have a fallback in case mapping didn&#8217;t succeed (you could also provide
the <literal>packageWithBaseClasses</literal> as fallback). That way the tests generated from <literal>src/test/resources/contract/com/</literal> contracts
will be extending the <literal>com.example.ComBase</literal> whereas the rest of tests will extend <literal>com.example.FooBase</literal>.</simpara>
</section>
<section xml:id="_invoking_generated_tests">
<title>Invoking generated tests</title>
<simpara>To ensure that provider side is complaint with defined contracts, you need to invoke:</simpara>
<programlisting language="bash" linenumbering="unnumbered">./gradlew generateContractTests test</programlisting>
</section>
<section xml:id="_spring_cloud_contract_verifier_on_consumer_side">
<title>Spring Cloud Contract Verifier on consumer side</title>
<simpara>In consumer service you need to configure Spring Cloud Contract Verifier plugin in exactly the same way as in case of provider. If you don&#8217;t want to use Stub Runner then you need to copy contracts stored in
<literal>src/test/resources/contracts</literal> and generate WireMock json stubs using:</simpara>
<programlisting language="bash" linenumbering="unnumbered">./gradlew generateClientStubs</programlisting>
<simpara>Note that <literal>stubsOutputDir</literal> option has to be set for stub generation to work.</simpara>
<simpara>When present, json stubs can be used in consumer automated tests.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@ContextConfiguration(loader == SpringApplicationContextLoader, classes == Application)
class LoanApplicationServiceSpec extends Specification {

 @ClassRule
 @Shared
 WireMockClassRule wireMockRule == new WireMockClassRule()

 @Autowired
 LoanApplicationService sut

 def 'should successfully apply for loan'() {
   given:
 	LoanApplication application =
			new LoanApplication(client: new Client(clientPesel: '12345678901'), amount: 123.123)
   when:
	LoanApplicationResult loanApplication == sut.loanApplication(application)
   then:
	loanApplication.loanApplicationStatus == LoanApplicationStatus.LOAN_APPLIED
	loanApplication.rejectionReason == null
 }
}</programlisting>
<simpara>Underneath LoanApplication makes a call to FraudDetection service. This request is handled by WireMock server configured using stubs generated by Spring Cloud Contract Verifier.</simpara>
</section>
</section>
<section xml:id="_using_in_your_maven_project">
<title>Using in your Maven project</title>
<section xml:id="_add_maven_plugin">
<title>Add maven plugin</title>
<simpara>Add the Spring Cloud Contract BOM</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependencyManagement&gt;
	&lt;dependencies&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
			&lt;artifactId&gt;spring-cloud-dependencies&lt;/artifactId&gt;
			&lt;version&gt;${spring-cloud-dependencies.version}&lt;/version&gt;
			&lt;type&gt;pom&lt;/type&gt;
			&lt;scope&gt;import&lt;/scope&gt;
		&lt;/dependency&gt;
	&lt;/dependencies&gt;
&lt;/dependencyManagement&gt;</programlisting>
<simpara>Next, the <literal>Spring Cloud Contract Verifier</literal> Maven plugin</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
	&lt;extensions&gt;true&lt;/extensions&gt;
	&lt;configuration&gt;
		&lt;packageWithBaseClasses&gt;com.example.fraud&lt;/packageWithBaseClasses&gt;
	&lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
<simpara>You can read more in the <link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract-maven-plugin/">Spring Cloud Contract Maven Plugin Docs</link></simpara>
</section>
<section xml:id="_maven_and_rest_assured_3_0">
<title>Maven and Rest Assured 3.0</title>
<simpara>By default Rest Assured 2.x is added to the classpath. However in order to give the users the
opportunity to use Rest Assured 3.x it&#8217;s enough to add it to the plugins classpath.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">&lt;plugin&gt;
    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
    &lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
    &lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
    &lt;extensions&gt;true&lt;/extensions&gt;
    &lt;configuration&gt;
        &lt;packageWithBaseClasses&gt;com.example&lt;/packageWithBaseClasses&gt;
    &lt;/configuration&gt;
    &lt;dependencies&gt;
        &lt;dependency&gt;
            &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
            &lt;artifactId&gt;spring-cloud-contract-verifier&lt;/artifactId&gt;
            &lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
        &lt;/dependency&gt;
        &lt;dependency&gt;
           &lt;groupId&gt;io.rest-assured&lt;/groupId&gt;
           &lt;artifactId&gt;rest-assured&lt;/artifactId&gt;
           &lt;version&gt;3.0.2&lt;/version&gt;
           &lt;scope&gt;compile&lt;/scope&gt;
        &lt;/dependency&gt;
        &lt;dependency&gt;
           &lt;groupId&gt;io.rest-assured&lt;/groupId&gt;
           &lt;artifactId&gt;spring-mock-mvc&lt;/artifactId&gt;
           &lt;version&gt;3.0.2&lt;/version&gt;
           &lt;scope&gt;compile&lt;/scope&gt;
        &lt;/dependency&gt;
    &lt;/dependencies&gt;
&lt;/plugin&gt;

&lt;dependencies&gt;
    &lt;!-- all dependencies --&gt;
    &lt;!-- you can exclude rest-assured from spring-cloud-contract-verifier --&gt;
    &lt;dependency&gt;
       &lt;groupId&gt;io.rest-assured&lt;/groupId&gt;
       &lt;artifactId&gt;rest-assured&lt;/artifactId&gt;
       &lt;version&gt;3.0.2&lt;/version&gt;
       &lt;scope&gt;test&lt;/scope&gt;
    &lt;/dependency&gt;
    &lt;dependency&gt;
       &lt;groupId&gt;io.rest-assured&lt;/groupId&gt;
       &lt;artifactId&gt;spring-mock-mvc&lt;/artifactId&gt;
       &lt;version&gt;3.0.2&lt;/version&gt;
       &lt;scope&gt;test&lt;/scope&gt;
    &lt;/dependency&gt;
&lt;/dependencies&gt;</programlisting>
<simpara>That way the plugin will automatically see that Rest Assured 3.x is present on the classpath
and will modify the imports accordingly.</simpara>
</section>
<section xml:id="_snapshot_versions_for_maven">
<title>Snapshot versions for Maven</title>
<simpara>For Snapshot / Milestone versions you have to add the following section to your <literal>pom.xml</literal></simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;repositories&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-snapshots&lt;/id&gt;
		&lt;name&gt;Spring Snapshots&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/snapshot&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;true&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-milestones&lt;/id&gt;
		&lt;name&gt;Spring Milestones&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/milestone&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-releases&lt;/id&gt;
		&lt;name&gt;Spring Releases&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/release&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
&lt;/repositories&gt;
&lt;pluginRepositories&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-snapshots&lt;/id&gt;
		&lt;name&gt;Spring Snapshots&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/snapshot&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;true&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-milestones&lt;/id&gt;
		&lt;name&gt;Spring Milestones&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/milestone&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-releases&lt;/id&gt;
		&lt;name&gt;Spring Releases&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/release&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
&lt;/pluginRepositories&gt;</programlisting>
</section>
<section xml:id="_add_stubs_2">
<title>Add stubs</title>
<simpara>By default Spring Cloud Contract Verifier is looking for stubs in <literal>src/test/resources/contracts</literal> directory.
Directory containing stub definitions is treated as a class name, and each stub definition is treated as a single test.
We assume that it contains at least one directory which will be used as test class name. If there is more than one level of nested directories all except the last one will be used as package name.
So with following structure</simpara>
<programlisting language="groovy" linenumbering="unnumbered">src/test/resources/contracts/myservice/shouldCreateUser.groovy
src/test/resources/contracts/myservice/shouldReturnUser.groovy</programlisting>
<simpara>Spring Cloud Contract Verifier will create test class <literal>defaultBasePackage.MyService</literal> with two methods
 - <literal>shouldCreateUser()</literal>
 - <literal>shouldReturnUser()</literal></simpara>
</section>
<section xml:id="_run_plugin_2">
<title>Run plugin</title>
<simpara>Plugin goal <literal>generateTests</literal> is assigned to be invoked in phase <literal>generate-test-sources</literal>. You have nothing to do as long as you want it to be part of your build process. If you just want to generate tests please invoke <literal>generateTests</literal> goal.</simpara>
</section>
<section xml:id="_configure_plugin_2">
<title>Configure plugin</title>
<simpara>To change default configuration just add <literal>configuration</literal> section to plugin definition or <literal>execution</literal> definition.</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
    &lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
    &lt;executions&gt;
        &lt;execution&gt;
            &lt;goals&gt;
                &lt;goal&gt;convert&lt;/goal&gt;
                &lt;goal&gt;generateStubs&lt;/goal&gt;
                &lt;goal&gt;generateTests&lt;/goal&gt;
            &lt;/goals&gt;
        &lt;/execution&gt;
    &lt;/executions&gt;
    &lt;configuration&gt;
        &lt;basePackageForTests&gt;org.springframework.cloud.verifier.twitter.place&lt;/basePackageForTests&gt;
        &lt;baseClassForTests&gt;org.springframework.cloud.verifier.twitter.place.BaseMockMvcSpec&lt;/baseClassForTests&gt;
    &lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
</section>
<section xml:id="_important_configuration_options">
<title>Important configuration options</title>
<itemizedlist>
<listitem>
<simpara><emphasis role="strong">testMode</emphasis> - defines mode for acceptance tests. By default <literal>MockMvc</literal> which is based on Spring&#8217;s MockMvc. It can also be changed to <literal>JaxRsClient</literal> or to <literal>Explicit</literal> for real HTTP calls.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">basePackageForTests</emphasis> - specifies base package for all generated tests. By default set to <literal>org.springframework.cloud.verifier.tests</literal>.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">ruleClassForTests</emphasis> - specifies Rule which should be added to generated test classes.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">baseClassForTests</emphasis> - base class for generated tests. By default <literal>spock.lang.Specification</literal> if using Spock tests.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsDirectory</emphasis> - directory containing contracts written using the GroovyDSL. By default <literal>/src/test/resources/contracts</literal>.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">testFramework</emphasis> - the target test framework to be used; currently Spock and JUnit are supported with JUnit being the default framework</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">packageWithBaseClasses</emphasis> - instead of providing a fixed value for base class you can provide a package where all the base classes lay.
The convention is such that if you have a contract under <literal>src/test/resources/contract/foo/bar/baz/</literal> and provide the value of this property
to <literal>com.example.base</literal> then we will assume that there is a <literal>BarBazBase</literal> class under <literal>com.example.base</literal> package. Takes precedence
over <emphasis role="strong">baseClassForTests</emphasis></simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">baseClassMappings</emphasis> - list of base class mappings that where you have to provide <literal>contractPackageRegex</literal> which is checked
against the package in which the contract lays and <literal>baseClassFQN</literal> that maps to fully qualified name of the base class for the matched
contract. If you have a contract under <literal>src/test/resources/contract/foo/bar/baz/</literal> and map the property <literal>.*</literal> &#8594; <literal>com.example.base.BaseClass</literal> then
the test class generated from these contracts will extend <literal>com.example.base.BaseClass</literal>. Takes precedence over <emphasis role="strong">packageWithBaseClasses</emphasis>
 and <emphasis role="strong">baseClassForTests</emphasis>.</simpara>
</listitem>
</itemizedlist>
<simpara>If you want to download your contract definitions from a Maven repository you can use</simpara>
<itemizedlist>
<listitem>
<simpara><emphasis role="strong">contractDependency</emphasis> - the contract dependency that contains all the packaged contracts</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsPath</emphasis> - path to concrete contracts in the JAR with packaged contracts. Defaults to <literal>groupid/artifactid</literal> where <literal>gropuid</literal> is slash separated.</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsWorkOffline</emphasis> - if the dependencies should be downloaded or local Maven only should be reused</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractsRepositoryUrl</emphasis> - <emphasis role="strong">DEPRECATED PROPERTY - please use the <literal>contractRepository</literal> closure</emphasis> - URL to a repo with the artifacts with contracts, if not provided should use the current Maven ones</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">contractRepository</emphasis> - closure where you can define properties related to repository with contracts</simpara>
<itemizedlist>
<listitem>
<simpara><emphasis role="strong">username</emphasis> - username to be used to connect to the repo</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">password</emphasis> - username to be used to connect to the repo</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">proxyHost</emphasis> - proxy host to be used to connect to the repo</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">proxyPort</emphasis> - proxy port to be used to connect to the repo</simpara>
</listitem>
<listitem>
<simpara><emphasis role="strong">cacheDownloadedContracts</emphasis> - if you want to reuse download JARs that contain contract definitions.
We cache only non-snapshot, explicitly provided versions (e.g. <literal>+</literal> or <literal>1.0.0.BUILD-SNAPSHOT</literal> won&#8217;t get cached).
By default this feature is turned on.</simpara>
</listitem>
</itemizedlist>
</listitem>
</itemizedlist>
</section>
<section xml:id="_single_base_class_for_all_tests_2">
<title>Single base class for all tests</title>
<simpara>When using Spring Cloud Contract Verifier in default MockMvc you need to create a base specification for all generated acceptance tests.
In this class you need to point to endpoint which should be verified.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.mycompany.tests

import org.mycompany.ExampleSpringController
import com.jayway.restassured.module.mockmvc.RestAssuredMockMvc
import spock.lang.Specification

class  MvcSpec extends Specification {
  def setup() {
   RestAssuredMockMvc.standaloneSetup(new ExampleSpringController())
  }
}</programlisting>
<simpara>In case of using <literal>Explicit</literal> mode, you can use base class to initialize the whole tested app similarly as in regular integration tests. In case of <literal>JAXRSCLIENT</literal> mode this base class should also contain <literal>protected WebTarget webTarget</literal> field, right now the only option to test JAX-RS API is to start a web server.</simpara>
</section>
<section xml:id="_different_base_classes_for_contracts_2">
<title>Different base classes for contracts</title>
<simpara>If your base classes differ between contracts you can tell the Spring Cloud Contract plugin which class should get
extended by the autogenerated tests. You have two options:</simpara>
<itemizedlist>
<listitem>
<simpara>follow a convention by providing the <literal>packageWithBaseClasses</literal></simpara>
</listitem>
<listitem>
<simpara>provide explicit mapping via <literal>baseClassMappings</literal></simpara>
</listitem>
</itemizedlist>
<simpara><emphasis role="strong">Convention</emphasis></simpara>
<simpara>The convention is such that if you have a contract under e.g. <literal>src/test/resources/contract/hello/v1/</literal> and provide the value of the <literal>packageWithBaseClasses</literal> property
to <literal>hello</literal> then we will assume that there is a <literal>HelloV1Base</literal> class under <literal>hello</literal> package. In other words we take last two parts of package
if they exist and form a class with a <literal>Base</literal> suffix. Takes precedence over <emphasis role="strong">baseClassForTests</emphasis>. Example of usage:</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;configuration&gt;
		&lt;packageWithBaseClasses&gt;hello&lt;/packageWithBaseClasses&gt;
	&lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
<simpara><emphasis role="strong">Mapping</emphasis></simpara>
<simpara>You can manually map a regular expression of the contract&#8217;s package to fully qualified name of the base class for the matched contract.
You have to provide a list <literal>baseClassMappings</literal> of <literal>baseClassMapping</literal> that takes a <literal>contractPackageRegex</literal> to <literal>baseClassFQN</literal> mapping.
Let&#8217;s take a look at the following example:</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;configuration&gt;
		&lt;baseClassForTests&gt;com.example.FooBase&lt;/baseClassForTests&gt;
		&lt;baseClassMappings&gt;
			&lt;baseClassMapping&gt;
				&lt;contractPackageRegex&gt;.*com.*&lt;/contractPackageRegex&gt;
				&lt;baseClassFQN&gt;com.example.TestBase&lt;/baseClassFQN&gt;
			&lt;/baseClassMapping&gt;
		&lt;/baseClassMappings&gt;
	&lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
<simpara>Let&#8217;s assume that you have contracts under
 - <literal>src/test/resources/contract/com/</literal>
 - <literal>src/test/resources/contract/foo/</literal></simpara>
<simpara>By providing the <literal>baseClassForTests</literal> we have a fallback in case mapping didn&#8217;t succeed (you could also provide
the <literal>packageWithBaseClasses</literal> as fallback). That way the tests generated from <literal>src/test/resources/contract/com/</literal> contracts
will be extending the <literal>com.example.ComBase</literal> whereas the rest of tests will extend <literal>com.example.FooBase</literal>.</simpara>
</section>
<section xml:id="_invoking_generated_tests_2">
<title>Invoking generated tests</title>
<simpara>Spring Cloud Contract Maven Plugin generates verification code into directory <literal>/generated-test-sources/contractVerifier</literal> and attach this directory to <literal>testCompile</literal> goal.</simpara>
<simpara>For Groovy Spock code use:</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.codehaus.gmavenplus&lt;/groupId&gt;
	&lt;artifactId&gt;gmavenplus-plugin&lt;/artifactId&gt;
	&lt;version&gt;1.5&lt;/version&gt;
	&lt;executions&gt;
		&lt;execution&gt;
			&lt;goals&gt;
				&lt;goal&gt;testCompile&lt;/goal&gt;
			&lt;/goals&gt;
		&lt;/execution&gt;
	&lt;/executions&gt;
	&lt;configuration&gt;
		&lt;testSources&gt;
			&lt;testSource&gt;
				&lt;directory&gt;${project.basedir}/src/test/groovy&lt;/directory&gt;
				&lt;includes&gt;
					&lt;include&gt;**/*.groovy&lt;/include&gt;
				&lt;/includes&gt;
			&lt;/testSource&gt;
			&lt;testSource&gt;
				&lt;directory&gt;${project.build.directory}/generated-test-sources/contractVerifier&lt;/directory&gt;
				&lt;includes&gt;
					&lt;include&gt;**/*.groovy&lt;/include&gt;
				&lt;/includes&gt;
			&lt;/testSource&gt;
		&lt;/testSources&gt;
	&lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
<simpara>To ensure that provider side is complaint with defined contracts, you need to invoke <literal>mvn generateTest test</literal></simpara>
</section>
<section xml:id="_faq_with_maven_plugin">
<title>FAQ with Maven Plugin</title>

</section>
<section xml:id="_maven_plugin_and_sts">
<title>Maven Plugin and STS</title>
<simpara>In case you see the following exception while using STS</simpara>
<informalfigure>
<mediaobject>
<imageobject>
<imagedata fileref="https://raw.githubusercontent.com/spring-cloud/spring-cloud-contract/1.0.x/docs/src/main/asciidoc/images/sts_exception.png"/>
</imageobject>
<textobject><phrase>STS Exception</phrase></textobject>
</mediaobject>
</informalfigure>
<simpara>when you click on the marker you should see sth like this</simpara>
<programlisting language="bash" linenumbering="unnumbered"> plugin:1.1.0.M1:convert:default-convert:process-test-resources) org.apache.maven.plugin.PluginExecutionException: Execution default-convert of goal org.springframework.cloud:spring-
 cloud-contract-maven-plugin:1.1.0.M1:convert failed. at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:145) at
 org.eclipse.m2e.core.internal.embedder.MavenImpl.execute(MavenImpl.java:331) at org.eclipse.m2e.core.internal.embedder.MavenImpl$11.call(MavenImpl.java:1362) at
...
 org.eclipse.core.internal.jobs.Worker.run(Worker.java:55) Caused by: java.lang.NullPointerException at
 org.eclipse.m2e.core.internal.builder.plexusbuildapi.EclipseIncrementalBuildContext.hasDelta(EclipseIncrementalBuildContext.java:53) at
 org.sonatype.plexus.build.incremental.ThreadBuildContext.hasDelta(ThreadBuildContext.java:59) at</programlisting>
<simpara>In order to fix this issue just provide the following section in your <literal>pom.xml</literal></simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;build&gt;
    &lt;pluginManagement&gt;
        &lt;plugins&gt;
            &lt;!--This plugin's configuration is used to store Eclipse m2e settings
                only. It has no influence on the Maven build itself. --&gt;
            &lt;plugin&gt;
                &lt;groupId&gt;org.eclipse.m2e&lt;/groupId&gt;
                &lt;artifactId&gt;lifecycle-mapping&lt;/artifactId&gt;
                &lt;version&gt;1.0.0&lt;/version&gt;
                &lt;configuration&gt;
                    &lt;lifecycleMappingMetadata&gt;
                        &lt;pluginExecutions&gt;
                             &lt;pluginExecution&gt;
                                &lt;pluginExecutionFilter&gt;
                                    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
                                    &lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
                                    &lt;versionRange&gt;[1.0,)&lt;/versionRange&gt;
                                    &lt;goals&gt;
                                        &lt;goal&gt;convert&lt;/goal&gt;
                                    &lt;/goals&gt;
                                &lt;/pluginExecutionFilter&gt;
                                &lt;action&gt;
                                    &lt;execute /&gt;
                                &lt;/action&gt;
                             &lt;/pluginExecution&gt;
                        &lt;/pluginExecutions&gt;
                    &lt;/lifecycleMappingMetadata&gt;
                &lt;/configuration&gt;
            &lt;/plugin&gt;
        &lt;/plugins&gt;
    &lt;/pluginManagement&gt;
&lt;/build&gt;</programlisting>
</section>
<section xml:id="_spring_cloud_contract_verifier_on_consumer_side_2">
<title>Spring Cloud Contract Verifier on consumer side</title>
<simpara>You can actually use the Spring Cloud Contract Verifier also for the consumer side!
You can use the plugin so that it only converts the contracts and generates the stubs.
To achieve that you need to configure Spring Cloud Contract Verifier plugin in exactly
the same way as in case of provider. You need to copy contracts stored in
<literal>src/test/resources/contracts</literal> and generate WireMock json stubs using:
<literal>mvn generateStubs</literal> command. By default generated WireMock mapping is
stored in directory <literal>target/mappings</literal>. Your project should create from
this generated mappings additional artifact with classifier <literal>stubs</literal> for
easy deploy to maven repository.</simpara>
<simpara>Sample configuration:</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
    &lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
    &lt;version&gt;${verifier-plugin.version}&lt;/version&gt;
    &lt;executions&gt;
        &lt;execution&gt;
            &lt;goals&gt;
                &lt;goal&gt;convert&lt;/goal&gt;
                &lt;goal&gt;generateStubs&lt;/goal&gt;
            &lt;/goals&gt;
        &lt;/execution&gt;
    &lt;/executions&gt;
&lt;/plugin&gt;</programlisting>
<simpara>When present, json stubs can be used in consumer automated tests.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@RunWith(SpringTestRunner.class)
@SpringBootTest
@AutoConfigureStubRunner
public class LoanApplicationServiceTests {

  @Autowired
  LoanApplicationService service;

  @Test
  public void shouldSuccessfullyApplyForLoan() {
    //given:
 	LoanApplication application =
			new LoanApplication(new Client("12345678901"), 123.123);
    //when:
	LoanApplicationResult loanApplication = service.loanApplication(application);
    // then:
	assertThat(loanApplication.loanApplicationStatus).isEqualTo(LoanApplicationStatus.LOAN_APPLIED);
	assertThat(loanApplication.rejectionReason).isNull();
  }
}</programlisting>
<simpara>Underneath <literal>LoanApplication</literal> makes a call to the <literal>FraudDetection</literal> service. This request is handled by
a WireMock server configured using stubs generated by Spring Cloud Contract Verifier.</simpara>
</section>
</section>
<section xml:id="_scenarios">
<title>Scenarios</title>
<simpara>It&#8217;s possible to handle scenarios with Spring Cloud Contract Verifier. All you need to do is to stick to proper naming convention while creating your contracts. The convention requires to include order number followed by the underscore.</simpara>
<screen>my_contracts_dir\
  scenario1\
    1_login.groovy
    2_showCart.groovy
    3_logout.groovy</screen>
<simpara>Such tree will cause Spring Cloud Contract Verifier generating WireMock&#8217;s scenario with name <literal>scenario1</literal> and three steps:</simpara>
<itemizedlist>
<listitem>
<simpara>login marked as <literal>Started</literal> pointing to:</simpara>
</listitem>
<listitem>
<simpara>showCart marked as <literal>Step1</literal> pointing to:</simpara>
</listitem>
<listitem>
<simpara>logout marked as <literal>Step2</literal> which will close the scenario.</simpara>
</listitem>
</itemizedlist>
<simpara>More details about WireMock scenarios can be found under <link xl:href="http://wiremock.org/stateful-behaviour.html">http://wiremock.org/stateful-behaviour.html</link></simpara>
<simpara>Spring Cloud Contract Verifier will also generate tests with guaranteed order of execution.</simpara>
</section>
<section xml:id="_stubs_and_transitive_dependencies">
<title>Stubs and transitive dependencies</title>
<simpara>The Maven and Gradle plugin that we&#8217;re created are adding the tasks that create the stubs jar for you. What can be problematic
is that when reusing the stubs you can by mistake import all of that stub dependencies! When building a Maven artifact
even though you have a couple of different jars, all of them share one pom:</simpara>
<programlisting language="bash" linenumbering="unnumbered">├── github-webhook-0.0.1.BUILD-20160903.075506-1-stubs.jar
├── github-webhook-0.0.1.BUILD-20160903.075506-1-stubs.jar.sha1
├── github-webhook-0.0.1.BUILD-20160903.075655-2-stubs.jar
├── github-webhook-0.0.1.BUILD-20160903.075655-2-stubs.jar.sha1
├── github-webhook-0.0.1.BUILD-SNAPSHOT.jar
├── github-webhook-0.0.1.BUILD-SNAPSHOT.pom
├── github-webhook-0.0.1.BUILD-SNAPSHOT-stubs.jar
├── ...
└── ...</programlisting>
<simpara>There are three possibilities of working with those dependencies so as not to have any issues with transitive dependencies.</simpara>
<simpara><emphasis role="strong">Mark all application dependencies as optional</emphasis></simpara>
<simpara>If in the <literal>github-webhook</literal> application we would mark all of our dependencies as optional, when you include the
<literal>github-webhook</literal> stubs in another application (or when that dependency gets downloaded by Stub Runner) then, since
all of the depenencies are optional, they will not get downloaded.</simpara>
<simpara><emphasis role="strong">Create a separate artifactid for stubs</emphasis></simpara>
<simpara>If you create a separate artifactid then you can set it up in whatever way you wish. For example by having no dependencies at all.</simpara>
<simpara><emphasis role="strong">Exclude dependencies on the consumer side</emphasis></simpara>
<simpara>As a consumer, if you add the stub dependency to your classpath you can explicitly exclude the unwanted dependencies.</simpara>
</section>
</chapter>
<chapter xml:id="_spring_cloud_contract_verifier_messaging">
<title>Spring Cloud Contract Verifier Messaging</title>
<simpara>Spring Cloud Contract Verifier allows you to verify your application that uses messaging as means of communication.
All of our integrations are working with Spring but you can also create one yourself and use it.</simpara>
<section xml:id="_integrations">
<title>Integrations</title>
<simpara>You can use one of the four integration configurations:</simpara>
<itemizedlist>
<listitem>
<simpara>Apache Camel</simpara>
</listitem>
<listitem>
<simpara>Spring Integration</simpara>
</listitem>
<listitem>
<simpara>Spring Cloud Stream</simpara>
</listitem>
<listitem>
<simpara>Spring AMQP</simpara>
</listitem>
</itemizedlist>
<simpara>Since we&#8217;re using Spring Boot then if you have added one of the aforementioned libraries
to the classpath then automatically all the messaging configuration will be set up.</simpara>
<important>
<simpara>Remember to put <literal>@AutoConfigureMessageVerifier</literal> on the base class of your
generated tests. Otherwise messaging part of Spring Cloud Contract Verifier will not work.</simpara>
</important>
<important>
<simpara>If you want to use Spring Cloud Stream remember to add a
<literal>org.springframework.cloud:spring-cloud-stream-test-support</literal> dependency.</simpara>
</important>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
    &lt;artifactId&gt;spring-cloud-stream-test-support&lt;/artifactId&gt;
    &lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">testCompile "org.springframework.cloud:spring-cloud-stream-test-support"</programlisting>
</para>
</formalpara>
</section>
<section xml:id="_manual_integration_testing">
<title>Manual Integration Testing</title>
<simpara>The main interface used by the tests is the <literal>org.springframework.cloud.contract.verifier.messaging.MessageVerifier</literal>.
It defines how to send and receive messages. You can create your own implementation to achieve the
same goal.</simpara>
<simpara>In the a test you can inject a <literal>ContractVerifierMessageExchange</literal> to send and receive messages that follow the contract.
Then add <literal>@AutoConfigureMessageVerifier</literal> to your test, e.g.</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringTestRunner.class)
@SpringBootTest
@AutoConfigureMessageVerifier
public static class MessagingContractTests {

  @Autowired
  private MessageVerifier verifier;
  ...
}</programlisting>
<note>
<simpara>If your tests require stubs as well, then
<literal>@AutoConfigureStubRunner</literal> includes the messaging configuration, so
you only need the one annotation.</simpara>
</note>
</section>
<section xml:id="_publisher_side_test_generation">
<title>Publisher side test generation</title>
<simpara>Having the <literal>input</literal> or <literal>outputMessage</literal> sections in your DSL will result in creation of tests on the publisher&#8217;s side. By default
JUnit tests will be created, however there is also a possibility to create Spock tests.</simpara>
<simpara>There are 3 main scenarios that we should take into consideration:</simpara>
<itemizedlist>
<listitem>
<simpara>Scenario 1: there is no input message that produces an output one. The output message is triggered by a component
inside the application (e.g. scheduler)</simpara>
</listitem>
<listitem>
<simpara>Scenario 2: the input message triggers an output message</simpara>
</listitem>
<listitem>
<simpara>Scenario 3: the input message is consumed and there is no output message</simpara>
</listitem>
</itemizedlist>
<important>
<simpara>The destination passed to <literal>messageFrom</literal> or <literal>sentTo</literal> can have different meanings for different
 messaging implementations. For <emphasis role="strong">Stream</emphasis> and <emphasis role="strong">Integration</emphasis> it&#8217;s first resolved as a <literal>destination</literal> of a channel, and then if
 there is no such <literal>destination</literal> it&#8217;s resolved as a channel name. For <emphasis role="strong">Camel</emphasis> that&#8217;s a certain component (e.x. <literal>jms</literal>).</simpara>
</important>
<simpara>Example for Camel:</simpara>
<section xml:id="_scenario_1_no_input_message">
<title>Scenario 1 (no input message)</title>
<simpara>For the given contract:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">def contractDsl = Contract.make {
	label 'some_label'
	input {
		triggeredBy('bookReturnedTriggered()')
	}
	outputMessage {
		sentTo('activemq:output')
		body('''{ "bookName" : "foo" }''')
		headers {
			header('BOOK-NAME', 'foo')
			messagingContentType(applicationJson())
		}
	}
}</programlisting>
<simpara>The following JUnit test will be created:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
 // when:
  bookReturnedTriggered();

 // then:
  ContractVerifierMessage response = contractVerifierMessaging.receive("activemq:output");
  assertThat(response).isNotNull();
  assertThat(response.getHeader("BOOK-NAME")).isNotNull();
  assertThat(response.getHeader("BOOK-NAME").toString()).isEqualTo("foo");
  assertThat(response.getHeader("contentType")).isNotNull();
  assertThat(response.getHeader("contentType").toString()).isEqualTo("application/json");
 // and:
  DocumentContext parsedJson = JsonPath.parse(contractVerifierObjectMapper.writeValueAsString(response.getPayload()));
  assertThatJson(parsedJson).field("bookName").isEqualTo("foo");
'''</programlisting>
<simpara>And the following Spock test would be created:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
 when:
  bookReturnedTriggered()

 then:
  ContractVerifierMessage response = contractVerifierMessaging.receive('activemq:output')
  assert response != null
  response.getHeader('BOOK-NAME')?.toString()  == 'foo'
  response.getHeader('contentType')?.toString()  == 'application/json'
 and:
  DocumentContext parsedJson = JsonPath.parse(contractVerifierObjectMapper.writeValueAsString(response.payload))
  assertThatJson(parsedJson).field("bookName").isEqualTo("foo")

'''</programlisting>
</section>
<section xml:id="_scenario_2_output_triggered_by_input">
<title>Scenario 2 (output triggered by input)</title>
<simpara>For the given contract:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">def contractDsl = Contract.make {
	label 'some_label'
	input {
		messageFrom('jms:input')
		messageBody([
				bookName: 'foo'
		])
		messageHeaders {
			header('sample', 'header')
		}
	}
	outputMessage {
		sentTo('jms:output')
		body([
				bookName: 'foo'
		])
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
<simpara>The following JUnit test will be created:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
// given:
 ContractVerifierMessage inputMessage = contractVerifierMessaging.create(
  "{\\"bookName\\":\\"foo\\"}"
, headers()
  .header("sample", "header"));

// when:
 contractVerifierMessaging.send(inputMessage, "jms:input");

// then:
 ContractVerifierMessage response = contractVerifierMessaging.receive("jms:output");
 assertThat(response).isNotNull();
 assertThat(response.getHeader("BOOK-NAME")).isNotNull();
 assertThat(response.getHeader("BOOK-NAME").toString()).isEqualTo("foo");
// and:
 DocumentContext parsedJson = JsonPath.parse(contractVerifierObjectMapper.writeValueAsString(response.getPayload()));
 assertThatJson(parsedJson).field("bookName").isEqualTo("foo");
'''</programlisting>
<simpara>And the following Spock test would be created:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">"""\
given:
   ContractVerifierMessage inputMessage = contractVerifierMessaging.create(
    '''{"bookName":"foo"}''',
    ['sample': 'header']
  )

when:
   contractVerifierMessaging.send(inputMessage, 'jms:input')

then:
   ContractVerifierMessage response = contractVerifierMessaging.receive('jms:output')
   assert response !- null
   response.getHeader('BOOK-NAME')?.toString()  == 'foo'
and:
   DocumentContext parsedJson = JsonPath.parse(contractVerifierObjectMapper.writeValueAsString(response.payload))
   assertThatJson(parsedJson).field("bookName").isEqualTo("foo")
"""</programlisting>
</section>
<section xml:id="_scenario_3_no_output_message">
<title>Scenario 3 (no output message)</title>
<simpara>For the given contract:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">def contractDsl = Contract.make {
	label 'some_label'
	input {
		messageFrom('jms:delete')
		messageBody([
				bookName: 'foo'
		])
		messageHeaders {
			header('sample', 'header')
		}
		assertThat('bookWasDeleted()')
	}
}</programlisting>
<simpara>The following JUnit test will be created:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
// given:
 ContractVerifierMessage inputMessage = contractVerifierMessaging.create(
	"{\\"bookName\\":\\"foo\\"}"
, headers()
	.header("sample", "header"));

// when:
 contractVerifierMessaging.send(inputMessage, "jms:delete");

// then:
 bookWasDeleted();
'''</programlisting>
<simpara>And the following Spock test would be created:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
given:
	 ContractVerifierMessage inputMessage = contractVerifierMessaging.create(
		\'\'\'{"bookName":"foo"}\'\'\',
		['sample': 'header']
	)

when:
	 contractVerifierMessaging.send(inputMessage, 'jms:delete')

then:
	 noExceptionThrown()
	 bookWasDeleted()
'''</programlisting>
</section>
</section>
<section xml:id="_consumer_stub_side_generation">
<title>Consumer Stub Side generation</title>
<simpara>Unlike the HTTP part - in Messaging we need to publish the Groovy DSL inside the JAR with a stub. Then it&#8217;s parsed on the consumer side
and proper stubbed routes are created.</simpara>
<simpara>For more information please consult the Stub Runner Messaging sections.</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependencies&gt;
	&lt;dependency&gt;
		&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
		&lt;artifactId&gt;spring-cloud-starter-stream-rabbit&lt;/artifactId&gt;
	&lt;/dependency&gt;

	&lt;dependency&gt;
		&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
		&lt;artifactId&gt;spring-cloud-starter-contract-stub-runner&lt;/artifactId&gt;
		&lt;scope&gt;test&lt;/scope&gt;
	&lt;/dependency&gt;
	&lt;dependency&gt;
		&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
		&lt;artifactId&gt;spring-cloud-stream-test-support&lt;/artifactId&gt;
		&lt;scope&gt;test&lt;/scope&gt;
	&lt;/dependency&gt;
&lt;/dependencies&gt;

&lt;dependencyManagement&gt;
	&lt;dependencies&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
			&lt;artifactId&gt;spring-cloud-dependencies&lt;/artifactId&gt;
			&lt;version&gt;Dalston.BUILD-SNAPSHOT&lt;/version&gt;
			&lt;type&gt;pom&lt;/type&gt;
			&lt;scope&gt;import&lt;/scope&gt;
		&lt;/dependency&gt;
	&lt;/dependencies&gt;
&lt;/dependencyManagement&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">ext {
	contractsDir = file("mappings")
	stubsOutputDirRoot = file("${project.buildDir}/production/${project.name}-stubs/")
}

// Automatically added by plugin:
// copyContracts - copies contracts to the output folder from which JAR will be created
// verifierStubsJar - JAR with a provided stub suffix
// the presented publication is also added by the plugin but you can modify it as you wish

publishing {
	publications {
		stubs(MavenPublication) {
			artifactId "${project.name}-stubs"
			artifact verifierStubsJar
		}
	}
}</programlisting>
</para>
</formalpara>
</section>
</chapter>
<chapter xml:id="_spring_cloud_contract_stub_runner">
<title>Spring Cloud Contract Stub Runner</title>
<simpara>One of the issues that you could have encountered while using Spring Cloud Contract Verifier was to pass the generated WireMock JSON stubs from the server side to the client side (or various clients).
 The same takes place in terms of client side generation for messaging.</simpara>
<simpara>Copying the JSON files / setting the client side for messaging manually is out of the question.</simpara>
<simpara>That&#8217;s why we&#8217;ll introduce Spring Cloud Contract Stub Runner that can download and run the stubs
automatically for you.</simpara>
<section xml:id="_snapshot_versions">
<title>Snapshot versions</title>
<simpara>Add the additional snapshot repository to your build.gradle to use snapshot versions which are automatically uploaded after every successful build:</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;repositories&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-snapshots&lt;/id&gt;
		&lt;name&gt;Spring Snapshots&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/snapshot&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;true&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-milestones&lt;/id&gt;
		&lt;name&gt;Spring Milestones&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/milestone&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
	&lt;repository&gt;
		&lt;id&gt;spring-releases&lt;/id&gt;
		&lt;name&gt;Spring Releases&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/release&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/repository&gt;
&lt;/repositories&gt;
&lt;pluginRepositories&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-snapshots&lt;/id&gt;
		&lt;name&gt;Spring Snapshots&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/snapshot&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;true&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-milestones&lt;/id&gt;
		&lt;name&gt;Spring Milestones&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/milestone&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
	&lt;pluginRepository&gt;
		&lt;id&gt;spring-releases&lt;/id&gt;
		&lt;name&gt;Spring Releases&lt;/name&gt;
		&lt;url&gt;https://repo.spring.io/release&lt;/url&gt;
		&lt;snapshots&gt;
			&lt;enabled&gt;false&lt;/enabled&gt;
		&lt;/snapshots&gt;
	&lt;/pluginRepository&gt;
&lt;/pluginRepositories&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">buildscript {
	repositories {
		mavenCentral()
		mavenLocal()
		maven { url "https://repo.spring.io/snapshot" }
		maven { url "https://repo.spring.io/milestone" }
		maven { url "https://repo.spring.io/release" }
	}</programlisting>
</para>
</formalpara>
</section>
<section xml:id="_publishing_stubs_as_jars">
<title>Publishing stubs as JARs</title>
<simpara>The easiest approach would be to centralize the way stubs are kept. For example you can keep them as JARs in a Maven repository.</simpara>
<tip>
<simpara>For both Maven and Gradle the setup comes out of the box. But you can customize it if you want to.</simpara>
</tip>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;!-- First disable the default jar setup in the properties section--&gt;
&lt;!-- we don't want the verifier to do a jar for us --&gt;
&lt;spring.cloud.contract.verifier.skip&gt;true&lt;/spring.cloud.contract.verifier.skip&gt;

&lt;!-- Next add the assembly plugin to your build --&gt;
&lt;!-- we want the assembly plugin to generate the JAR --&gt;
&lt;plugin&gt;
	&lt;groupId&gt;org.apache.maven.plugins&lt;/groupId&gt;
	&lt;artifactId&gt;maven-assembly-plugin&lt;/artifactId&gt;
	&lt;executions&gt;
		&lt;execution&gt;
			&lt;id&gt;stub&lt;/id&gt;
			&lt;phase&gt;prepare-package&lt;/phase&gt;
			&lt;goals&gt;
				&lt;goal&gt;single&lt;/goal&gt;
			&lt;/goals&gt;
			&lt;inherited&gt;false&lt;/inherited&gt;
			&lt;configuration&gt;
				&lt;attach&gt;true&lt;/attach&gt;
				&lt;descriptors&gt;
					${basedir}/src/assembly/stub.xml
				&lt;/descriptors&gt;
			&lt;/configuration&gt;
		&lt;/execution&gt;
	&lt;/executions&gt;
&lt;/plugin&gt;

&lt;!-- Finally setup your assembly. Below you can find the contents of src/main/assembly/stub.xml --&gt;
&lt;assembly
	xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3 https://maven.apache.org/xsd/assembly-1.1.3.xsd"&gt;
	&lt;id&gt;stubs&lt;/id&gt;
	&lt;formats&gt;
		&lt;format&gt;jar&lt;/format&gt;
	&lt;/formats&gt;
	&lt;includeBaseDirectory&gt;false&lt;/includeBaseDirectory&gt;
	&lt;fileSets&gt;
		&lt;fileSet&gt;
			&lt;directory&gt;src/main/java&lt;/directory&gt;
			&lt;outputDirectory&gt;/&lt;/outputDirectory&gt;
			&lt;includes&gt;
				&lt;include&gt;**com/example/model/*.*&lt;/include&gt;
			&lt;/includes&gt;
		&lt;/fileSet&gt;
		&lt;fileSet&gt;
			&lt;directory&gt;${project.build.directory}/classes&lt;/directory&gt;
			&lt;outputDirectory&gt;/&lt;/outputDirectory&gt;
			&lt;includes&gt;
				&lt;include&gt;**com/example/model/*.*&lt;/include&gt;
			&lt;/includes&gt;
		&lt;/fileSet&gt;
		&lt;fileSet&gt;
			&lt;directory&gt;${project.build.directory}/snippets/stubs&lt;/directory&gt;
			&lt;outputDirectory&gt;META-INF/${project.groupId}/${project.artifactId}/${project.version}/mappings&lt;/outputDirectory&gt;
			&lt;includes&gt;
				&lt;include&gt;**/*&lt;/include&gt;
			&lt;/includes&gt;
		&lt;/fileSet&gt;
		&lt;fileSet&gt;
			&lt;directory&gt;${basedir}/src/test/resources/contracts&lt;/directory&gt;
			&lt;outputDirectory&gt;META-INF/${project.groupId}/${project.artifactId}/${project.version}/contracts&lt;/outputDirectory&gt;
			&lt;includes&gt;
				&lt;include&gt;**/*.groovy&lt;/include&gt;
			&lt;/includes&gt;
		&lt;/fileSet&gt;
	&lt;/fileSets&gt;
&lt;/assembly&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">ext {
	contractsDir = file("mappings")
	stubsOutputDirRoot = file("${project.buildDir}/production/${project.name}-stubs/")
}

// Automatically added by plugin:
// copyContracts - copies contracts to the output folder from which JAR will be created
// verifierStubsJar - JAR with a provided stub suffix
// the presented publication is also added by the plugin but you can modify it as you wish

publishing {
	publications {
		stubs(MavenPublication) {
			artifactId "${project.name}-stubs"
			artifact verifierStubsJar
		}
	}
}</programlisting>
</para>
</formalpara>
</section>
<section xml:id="_stub_runner_core">
<title>Stub Runner Core</title>
<simpara>Runs stubs for service collaborators. Treating stubs as contracts of services allows to use stub-runner as an implementation of
<link xl:href="https://martinfowler.com/articles/consumerDrivenContracts.html">Consumer Driven Contracts</link>.</simpara>
<simpara>Stub Runner allows you to automatically download the stubs of the provided dependencies (or pick those from the classpath), start WireMock servers for them and feed them with proper stub definitions.
For messaging, special stub routes are defined.</simpara>
<section xml:id="_retrieving_stubs">
<title>Retrieving stubs</title>
<simpara>You can pick the following options of acquiring stubs</simpara>
<itemizedlist>
<listitem>
<simpara>Aether based solution that downloads JARs with stubs from Artifactory / Nexus</simpara>
</listitem>
<listitem>
<simpara>Classpath scanning solution that searches classpath via pattern to retrieve stubs</simpara>
</listitem>
<listitem>
<simpara>Write your own implementation of the <literal>org.springframework.cloud.contract.stubrunner.StubDownloaderBuilder</literal> for full customization</simpara>
</listitem>
</itemizedlist>
<simpara>The latter example is described in the <link linkend="custom_stub_runner">Custom Stub Runner</link> section.</simpara>
<section xml:id="_stub_downloading">
<title>Stub downloading</title>
<simpara>If you provide the <literal>stubrunner.repositoryRoot</literal> or <literal>stubrunner.workOffline</literal> flag will be set
to <literal>true</literal> then Stub Runner will connect to the given server and download the required jars.
It will then unpack the JAR to a temporary folder and reference those files in further
contract processing.</simpara>
<simpara>Example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@AutoConfigureStubRunner(repositoryRoot="https://foo.bar", ids = "com.example:beer-api-producer:+:stubs:8095")</programlisting>
</section>
<section xml:id="_classpath_scanning">
<title>Classpath scanning</title>
<simpara>If you <emphasis role="strong">DON&#8217;T</emphasis> provide the <literal>stubrunner.repositoryRoot</literal> and <literal>stubrunner.workOffline</literal> flag will
be set to <literal>false</literal> (that&#8217;s the default) then classpath will get scanned. Let&#8217;s look at the
following example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@AutoConfigureStubRunner(ids = {
    "com.example:beer-api-producer:+:stubs:8095",
    "com.example.foo:bar:1.0.0:superstubs:8096"
})</programlisting>
<simpara>If you&#8217;ve added the dependencies to your classpath</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
    &lt;groupId&gt;com.example&lt;/groupId&gt;
    &lt;artifactId&gt;beer-api-producer-restdocs&lt;/artifactId&gt;
    &lt;classifier&gt;stubs&lt;/classifier&gt;
    &lt;version&gt;0.0.1-SNAPSHOT&lt;/version&gt;
    &lt;scope&gt;test&lt;/scope&gt;
    &lt;exclusions&gt;
        &lt;exclusion&gt;
            &lt;groupId&gt;*&lt;/groupId&gt;
            &lt;artifactId&gt;*&lt;/artifactId&gt;
        &lt;/exclusion&gt;
    &lt;/exclusions&gt;
&lt;/dependency&gt;
&lt;dependency&gt;
    &lt;groupId&gt;com.example.foo&lt;/groupId&gt;
    &lt;artifactId&gt;bar&lt;/artifactId&gt;
    &lt;classifier&gt;superstubs&lt;/classifier&gt;
    &lt;version&gt;1.0.0&lt;/version&gt;
    &lt;scope&gt;test&lt;/scope&gt;
    &lt;exclusions&gt;
        &lt;exclusion&gt;
            &lt;groupId&gt;*&lt;/groupId&gt;
            &lt;artifactId&gt;*&lt;/artifactId&gt;
        &lt;/exclusion&gt;
    &lt;/exclusions&gt;
&lt;/dependency&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">testCompile("com.example:beer-api-producer-restdocs:0.0.1-SNAPSHOT:stubs") {
    transitive = false
}
testCompile("com.example.foo:bar:1.0.0:superstubs") {
    transitive = false
}</programlisting>
</para>
</formalpara>
<simpara>Then the following locations on your classpath will get scanned. For <literal>com.example:beer-api-producer-restdocs</literal></simpara>
<itemizedlist>
<listitem>
<simpara>/META-INF/com.example/beer-api-producer-restdocs/<emphasis role="strong">*/</emphasis>.*</simpara>
</listitem>
<listitem>
<simpara>/contracts/com.example/beer-api-producer-restdocs/<emphasis role="strong">*/</emphasis>.*</simpara>
</listitem>
<listitem>
<simpara>/mappings/com.example/beer-api-producer-restdocs/<emphasis role="strong">*/</emphasis>.*</simpara>
</listitem>
</itemizedlist>
<simpara>and <literal>com.example.foo:bar</literal></simpara>
<itemizedlist>
<listitem>
<simpara>/META-INF/com.example.foo/bar/<emphasis role="strong">*/</emphasis>.*</simpara>
</listitem>
<listitem>
<simpara>/contracts/com.example.foo/bar/<emphasis role="strong">*/</emphasis>.*</simpara>
</listitem>
<listitem>
<simpara>/mappings/com.example.foo/bar/<emphasis role="strong">*/</emphasis>.*</simpara>
</listitem>
</itemizedlist>
<tip>
<simpara>As you can see you have to explicitly provide the group and artifact ids when packaging the
producer stubs.</simpara>
</tip>
<simpara>The producer would setup the contracts like this:</simpara>
<programlisting language="bash" linenumbering="unnumbered">└── src
    └── test
        └── resources
            └── contracts
                └── com.example
                    └── beer-api-producer-restdocs
                        └── nested
                            └── contract3.groovy</programlisting>
<simpara>To achieve proper stub packaging.</simpara>
<simpara>Or using the <link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples/blob/master/producer_with_restdocs/pom.xml">Maven <literal>assembly</literal> plugin</link> or
<link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples/blob/master/producer_with_restdocs/build.gradle">Gradle Jar</link> task you have to create the following
structure in your stubs jar.</simpara>
<programlisting language="bash" linenumbering="unnumbered">└── META-INF
    └── com.example
        └── beer-api-producer-restdocs
            └── 2.0.0
                ├── contracts
                │   └── nested
                │       └── contract2.groovy
                └── mappings
                    └── mapping.json</programlisting>
<simpara>By maintaining this structure classpath gets scanned and you can profit from the messaging /
HTTP stubs without the need to download artifacts.</simpara>
</section>
</section>
<section xml:id="_running_stubs">
<title>Running stubs</title>
<section xml:id="_limitations">
<title>Limitations</title>
<important>
<simpara>There might be a problem with StubRunner shutting down ports between tests. You might
 have a situation in which you get port conflicts. As long as you use the same context across tests
 everything works fine. But when the context are different (e.g. different stubs or different profiles)
 then you have to either use <literal>@DirtiesContext</literal> to shut down the stub servers, or else run them on
 different ports per test.</simpara>
</important>
</section>
<section xml:id="_running_using_main_app">
<title>Running using main app</title>
<simpara>You can set the following options to the main class:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">-c, --classifier                Suffix for the jar containing stubs (e.
                                  g. 'stubs' if the stub jar would
                                  have a 'stubs' classifier for stubs:
                                  foobar-stubs ). Defaults to 'stubs'
                                  (default: stubs)
--maxPort, --maxp &lt;Integer&gt;     Maximum port value to be assigned to
                                  the WireMock instance. Defaults to
                                  15000 (default: 15000)
--minPort, --minp &lt;Integer&gt;     Minimum port value to be assigned to
                                  the WireMock instance. Defaults to
                                  10000 (default: 10000)
-p, --password                  Password to user when connecting to
                                  repository
--phost, --proxyHost            Proxy host to use for repository
                                  requests
--pport, --proxyPort [Integer]  Proxy port to use for repository
                                  requests
-r, --root                      Location of a Jar containing server
                                  where you keep your stubs (e.g. http:
                                  //nexus.
                                  net/content/repositories/repository)
-s, --stubs                     Comma separated list of Ivy
                                  representation of jars with stubs.
                                  Eg. groupid:artifactid1,groupid2:
                                  artifactid2:classifier
-u, --username                  Username to user when connecting to
                                  repository
--wo, --workOffline             Switch to work offline. Defaults to
                                  'false'</programlisting>
</section>
<section xml:id="_http_stubs">
<title>HTTP Stubs</title>
<simpara>Stubs are defined in JSON documents, whose syntax is defined in <link xl:href="http://wiremock.org/stubbing.html">WireMock documentation</link></simpara>
<simpara>Example:</simpara>
<programlisting language="javascript" linenumbering="unnumbered">{
    "request": {
        "method": "GET",
        "url": "/ping"
    },
    "response": {
        "status": 200,
        "body": "pong",
        "headers": {
            "Content-Type": "text/plain"
        }
    }
}</programlisting>
</section>
<section xml:id="_viewing_registered_mappings">
<title>Viewing registered mappings</title>
<simpara>Every stubbed collaborator exposes list of defined mappings under <literal>__/admin/</literal> endpoint.</simpara>
</section>
<section xml:id="_messaging_stubs">
<title>Messaging Stubs</title>
<simpara>Depending on the provided Stub Runner dependency and the DSL the messaging routes are automatically set up.</simpara>
</section>
</section>
</section>
<section xml:id="_stub_runner_junit_rule">
<title>Stub Runner JUnit Rule</title>
<simpara>Stub Runner comes with a JUnit rule thanks to which you can very easily download and run stubs for given group and artifact id:</simpara>
<programlisting language="java" linenumbering="unnumbered">@ClassRule public static StubRunnerRule rule = new StubRunnerRule()
		.repoRoot(repoRoot())
		.downloadStub("org.springframework.cloud.contract.verifier.stubs", "loanIssuance")
		.downloadStub("org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer");</programlisting>
<simpara>After that rule gets executed Stub Runner connects to your Maven repository and for the given list of dependencies tries to:</simpara>
<itemizedlist>
<listitem>
<simpara>download them</simpara>
</listitem>
<listitem>
<simpara>cache them locally</simpara>
</listitem>
<listitem>
<simpara>unzip them to a temporary folder</simpara>
</listitem>
<listitem>
<simpara>start a WireMock server for each Maven dependency on a random port from the provided range of ports / provided port</simpara>
</listitem>
<listitem>
<simpara>feed the WireMock server with all JSON files that are valid WireMock definitions</simpara>
</listitem>
<listitem>
<simpara>can also send messages (remember to pass an implementation of <literal>MessageVerifier</literal> interface)</simpara>
</listitem>
</itemizedlist>
<simpara>Stub Runner uses <link xl:href="https://wiki.eclipse.org/Aether">Eclipse Aether</link> mechanism to download the Maven dependencies.
Check their <link xl:href="https://wiki.eclipse.org/Aether">docs</link> for more information.</simpara>
<simpara>Since the <literal>StubRunnerRule</literal> implements the <literal>StubFinder</literal> it allows you to find the started stubs:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.stubrunner;

import java.net.URL;
import java.util.Collection;
import java.util.Map;

import org.springframework.cloud.contract.spec.Contract;

public interface StubFinder extends StubTrigger {
	/**
	 * For the given groupId and artifactId tries to find the matching
	 * URL of the running stub.
	 *
	 * @param groupId - might be null. In that case a search only via artifactId takes place
	 * @return URL of a running stub or throws exception if not found
	 */
	URL findStubUrl(String groupId, String artifactId) throws StubNotFoundException;

	/**
	 * For the given Ivy notation {@code [groupId]:artifactId:[version]:[classifier]} tries to
	 * find the matching URL of the running stub. You can also pass only {@code artifactId}.
	 *
	 * @param ivyNotation - Ivy representation of the Maven artifact
	 * @return URL of a running stub or throws exception if not found
	 */
	URL findStubUrl(String ivyNotation) throws StubNotFoundException;

	/**
	 * Returns all running stubs
	 */
	RunningStubs findAllRunningStubs();

	/**
	 * Returns the list of Contracts
	 */
	Map&lt;StubConfiguration, Collection&lt;Contract&gt;&gt; getContracts();
}</programlisting>
<simpara>Example of usage in Spock tests:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@ClassRule @Shared StubRunnerRule rule = new StubRunnerRule()
		.repoRoot(StubRunnerRuleSpec.getResource("/m2repo/repository").toURI().toString())
		.downloadStub("org.springframework.cloud.contract.verifier.stubs", "loanIssuance")
		.downloadStub("org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer")

def 'should start WireMock servers'() {
	expect: 'WireMocks are running'
		rule.findStubUrl('org.springframework.cloud.contract.verifier.stubs', 'loanIssuance') != null
		rule.findStubUrl('loanIssuance') != null
		rule.findStubUrl('loanIssuance') == rule.findStubUrl('org.springframework.cloud.contract.verifier.stubs', 'loanIssuance')
		rule.findStubUrl('org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer') != null
	and:
		rule.findAllRunningStubs().isPresent('loanIssuance')
		rule.findAllRunningStubs().isPresent('org.springframework.cloud.contract.verifier.stubs', 'fraudDetectionServer')
		rule.findAllRunningStubs().isPresent('org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer')
	and: 'Stubs were registered'
		"${rule.findStubUrl('loanIssuance').toString()}/name".toURL().text == 'loanIssuance'
		"${rule.findStubUrl('fraudDetectionServer').toString()}/name".toURL().text == 'fraudDetectionServer'
}</programlisting>
<simpara>Example of usage in JUnit tests:</simpara>
<programlisting language="java" linenumbering="unnumbered">@Test
public void should_start_wiremock_servers() throws Exception {
	// expect: 'WireMocks are running'
		then(rule.findStubUrl("org.springframework.cloud.contract.verifier.stubs", "loanIssuance")).isNotNull();
		then(rule.findStubUrl("loanIssuance")).isNotNull();
		then(rule.findStubUrl("loanIssuance")).isEqualTo(rule.findStubUrl("org.springframework.cloud.contract.verifier.stubs", "loanIssuance"));
		then(rule.findStubUrl("org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer")).isNotNull();
	// and:
		then(rule.findAllRunningStubs().isPresent("loanIssuance")).isTrue();
		then(rule.findAllRunningStubs().isPresent("org.springframework.cloud.contract.verifier.stubs", "fraudDetectionServer")).isTrue();
		then(rule.findAllRunningStubs().isPresent("org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer")).isTrue();
	// and: 'Stubs were registered'
		then(httpGet(rule.findStubUrl("loanIssuance").toString() + "/name")).isEqualTo("loanIssuance");
		then(httpGet(rule.findStubUrl("fraudDetectionServer").toString() + "/name")).isEqualTo("fraudDetectionServer");
}</programlisting>
<simpara>Check the <emphasis role="strong">Common properties for JUnit and Spring</emphasis> for more information on how to apply global configuration of Stub Runner.</simpara>
<important>
<simpara>To use the JUnit rule together with messaging you have to provide an implementation of the
<literal>MessageVerifier</literal> interface to the rule builder (e.g. <literal>rule.messageVerifier(new MyMessageVerifier())</literal>).
If you don&#8217;t do this then whenever you try to send a message an exception will be thrown.</simpara>
</important>
<section xml:id="_maven_settings">
<title>Maven settings</title>
<simpara>The stub downloader honors Maven settings for a different local repository folder.
Authentication details for repositories and profiles are currently not taken into account, so you need to specify it using the properties mentioned above.</simpara>
</section>
<section xml:id="_providing_fixed_ports">
<title>Providing fixed ports</title>
<simpara>You can also run your stubs on fixed ports. You can do it in two different ways. One is to pass it in the properties, and the other via fluent API of
JUnit rule.</simpara>
</section>
<section xml:id="_fluent_api">
<title>Fluent API</title>
<simpara>When using the <literal>StubRunnerRule</literal> you can add a stub to download and then pass the port for the last downloaded stub.</simpara>
<programlisting language="java" linenumbering="unnumbered">@ClassRule public static StubRunnerRule rule = new StubRunnerRule()
		.repoRoot(repoRoot())
		.downloadStub("org.springframework.cloud.contract.verifier.stubs", "loanIssuance")
		.withPort(12345)
		.downloadStub("org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer:12346");</programlisting>
<simpara>You can see that for this example the following test is valid:</simpara>
<programlisting language="java" linenumbering="unnumbered">then(rule.findStubUrl("loanIssuance")).isEqualTo(URI.create("http://localhost:12345").toURL());
then(rule.findStubUrl("fraudDetectionServer")).isEqualTo(URI.create("http://localhost:12346").toURL());</programlisting>
</section>
<section xml:id="_stub_runner_with_spring">
<title>Stub Runner with Spring</title>
<simpara>Sets up Spring configuration of the Stub Runner project.</simpara>
<simpara>By providing a list of stubs inside your configuration file the Stub Runner automatically downloads
and registers in WireMock the selected stubs.</simpara>
<simpara>If you want to find the URL of your stubbed dependency you can autowire the <literal>StubFinder</literal> interface and use
its methods as presented below:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@ContextConfiguration(classes = Config, loader = SpringBootContextLoader)
@SpringBootTest(properties = [" stubrunner.cloud.enabled=false",
		"stubrunner.camel.enabled=false",
		'foo=${stubrunner.runningstubs.fraudDetectionServer.port}'])
@AutoConfigureStubRunner
@DirtiesContext
@ActiveProfiles("test")
class StubRunnerConfigurationSpec extends Specification {

	@Autowired StubFinder stubFinder
	@Autowired Environment environment
	@Value('${foo}') Integer foo

	@BeforeClass
	@AfterClass
	void setupProps() {
		System.clearProperty("stubrunner.repository.root")
		System.clearProperty("stubrunner.classifier")
	}

	def 'should start WireMock servers'() {
		expect: 'WireMocks are running'
			stubFinder.findStubUrl('org.springframework.cloud.contract.verifier.stubs', 'loanIssuance') != null
			stubFinder.findStubUrl('loanIssuance') != null
			stubFinder.findStubUrl('loanIssuance') == stubFinder.findStubUrl('org.springframework.cloud.contract.verifier.stubs', 'loanIssuance')
			stubFinder.findStubUrl('loanIssuance') == stubFinder.findStubUrl('org.springframework.cloud.contract.verifier.stubs:loanIssuance')
			stubFinder.findStubUrl('org.springframework.cloud.contract.verifier.stubs:loanIssuance:0.0.1-SNAPSHOT') == stubFinder.findStubUrl('org.springframework.cloud.contract.verifier.stubs:loanIssuance:0.0.1-SNAPSHOT:stubs')
			stubFinder.findStubUrl('org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer') != null
		and:
			stubFinder.findAllRunningStubs().isPresent('loanIssuance')
			stubFinder.findAllRunningStubs().isPresent('org.springframework.cloud.contract.verifier.stubs', 'fraudDetectionServer')
			stubFinder.findAllRunningStubs().isPresent('org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer')
		and: 'Stubs were registered'
			"${stubFinder.findStubUrl('loanIssuance').toString()}/name".toURL().text == 'loanIssuance'
			"${stubFinder.findStubUrl('fraudDetectionServer').toString()}/name".toURL().text == 'fraudDetectionServer'
	}

	def 'should throw an exception when stub is not found'() {
		when:
			stubFinder.findStubUrl('nonExistingService')
		then:
			thrown(StubNotFoundException)
		when:
			stubFinder.findStubUrl('nonExistingGroupId', 'nonExistingArtifactId')
		then:
			thrown(StubNotFoundException)
	}

	def 'should register started servers as environment variables'() {
		expect:
			environment.getProperty("stubrunner.runningstubs.loanIssuance.port") != null
			stubFinder.findAllRunningStubs().getPort("loanIssuance") == (environment.getProperty("stubrunner.runningstubs.loanIssuance.port") as Integer)
		and:
			environment.getProperty("stubrunner.runningstubs.fraudDetectionServer.port") != null
			stubFinder.findAllRunningStubs().getPort("fraudDetectionServer") == (environment.getProperty("stubrunner.runningstubs.fraudDetectionServer.port") as Integer)
	}

	def 'should be able to interpolate a running stub in the passed test property'() {
		given:
			int fraudPort = stubFinder.findAllRunningStubs().getPort("fraudDetectionServer")
		expect:
			fraudPort &gt; 0
			environment.getProperty("foo", Integer) == fraudPort
			foo == fraudPort
	}

	@Configuration
	@EnableAutoConfiguration
	static class Config {}
}</programlisting>
<simpara>for the following configuration file:</simpara>
<programlisting language="yml" linenumbering="unnumbered">stubrunner:
  repositoryRoot: classpath:m2repo/repository/
  ids:
    - org.springframework.cloud.contract.verifier.stubs:loanIssuance
    - org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer
    - org.springframework.cloud.contract.verifier.stubs:bootService</programlisting>
<simpara>Instead of using the properties you can also use the properties inside the <literal>@AutoConfigureStubRunner</literal>.
Below you can find an example of achieving the same result by setting values on the annotation.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@AutoConfigureStubRunner(
		ids = ["org.springframework.cloud.contract.verifier.stubs:loanIssuance",
		"org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer",
		"org.springframework.cloud.contract.verifier.stubs:bootService"],
		repositoryRoot = "classpath:m2repo/repository/")</programlisting>
<simpara>Stub Runner Spring registers environment variables in the following manner
for every registered WireMock server. Example for Stub Runner ids
 <literal>com.example:foo</literal>, <literal>com.example:bar</literal>.</simpara>
<itemizedlist>
<listitem>
<simpara><literal>stubrunner.runningstubs.foo.port</literal></simpara>
</listitem>
<listitem>
<simpara><literal>stubrunner.runningstubs.bar.port</literal></simpara>
</listitem>
</itemizedlist>
<simpara>Which you can reference in your code.</simpara>
</section>
</section>
<section xml:id="_stub_runner_spring_cloud">
<title>Stub Runner Spring Cloud</title>
<simpara>Stub Runner can integrate with Spring Cloud.</simpara>
<simpara>For real life examples you can check the</simpara>
<itemizedlist>
<listitem>
<simpara><link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples/tree/master/producer">producer app sample</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples/tree/master/consumer_with_discovery">consumer app sample</link></simpara>
</listitem>
</itemizedlist>
<section xml:id="_stubbing_service_discovery">
<title>Stubbing Service Discovery</title>
<simpara>The most important feature of <literal>Stub Runner Spring Cloud</literal> is the fact that it&#8217;s stubbing</simpara>
<itemizedlist>
<listitem>
<simpara><literal>DiscoveryClient</literal></simpara>
</listitem>
<listitem>
<simpara><literal>Ribbon</literal> <literal>ServerList</literal></simpara>
</listitem>
</itemizedlist>
<simpara>that means that regardless of the fact whether you&#8217;re using Zookeeper, Consul, Eureka or anything else, you don&#8217;t need that in your tests.
We&#8217;re starting WireMock instances of your dependencies and we&#8217;re telling your application whenever you&#8217;re using <literal>Feign</literal>, load balanced <literal>RestTemplate</literal>
or <literal>DiscoveryClient</literal> directly, to call those stubbed servers instead of calling the real Service Discovery tool.</simpara>
<simpara>For example this test will pass</simpara>
<programlisting language="groovy" linenumbering="unnumbered">def 'should make service discovery work'() {
	expect: 'WireMocks are running'
		"${stubFinder.findStubUrl('loanIssuance').toString()}/name".toURL().text == 'loanIssuance'
		"${stubFinder.findStubUrl('fraudDetectionServer').toString()}/name".toURL().text == 'fraudDetectionServer'
	and: 'Stubs can be reached via load service discovery'
		restTemplate.getForObject('http://loanIssuance/name', String) == 'loanIssuance'
		restTemplate.getForObject('http://someNameThatShouldMapFraudDetectionServer/name', String) == 'fraudDetectionServer'
}</programlisting>
<simpara>for the following configuration file</simpara>
<programlisting language="yml" linenumbering="unnumbered">stubrunner:
  idsToServiceIds:
    ivyNotation: someValueInsideYourCode
    fraudDetectionServer: someNameThatShouldMapFraudDetectionServer</programlisting>
<section xml:id="_test_profiles_and_service_discovery">
<title>Test profiles and service discovery</title>
<simpara>In your integration tests you typically don&#8217;t want to call neither a discovery service (e.g. Eureka)
or Config Server. That&#8217;s why you create an additional test configuration in which you want to disable
these features.</simpara>
<simpara>Due to certain limitations of <link xl:href="https://github.com/spring-cloud/spring-cloud-commons/issues/156"><literal>spring-cloud-commons</literal></link> to achieve this you have disable these properties
via a static block like presented below (example for Eureka)</simpara>
<programlisting language="java" linenumbering="unnumbered">    //Hack to work around https://github.com/spring-cloud/spring-cloud-commons/issues/156
    static {
        System.setProperty("eureka.client.enabled", "false");
        System.setProperty("spring.cloud.config.failFast", "false");
    }</programlisting>
</section>
</section>
<section xml:id="_additional_configuration">
<title>Additional Configuration</title>
<simpara>You can match the artifactId of the stub with the name of your app by using the <literal>stubrunner.idsToServiceIds:</literal> map.
You can disable Stub Runner Ribbon support by providing: <literal>stubrunner.cloud.ribbon.enabled</literal> equal to <literal>false</literal>
You can disable Stub Runner support by providing: <literal>stubrunner.cloud.enabled</literal> equal to <literal>false</literal></simpara>
<tip>
<simpara>By default all service discovery will be stubbed. That means that regardless of the fact if you have
an existing <literal>DiscoveryClient</literal> its results will be ignored. However, if you want to reuse it, just set
 <literal>stubrunner.cloud.delegate.enabled</literal> to <literal>true</literal> and then your existing <literal>DiscoveryClient</literal> results will be
 merged with the stubbed ones.</simpara>
</tip>
</section>
</section>
<section xml:id="_stub_runner_boot_application">
<title>Stub Runner Boot Application</title>
<simpara>Spring Cloud Contract Stub Runner Boot is a Spring Boot application that exposes REST endpoints to
trigger the messaging labels and to access started WireMock servers.</simpara>
<simpara>One of the use-cases is to run some smoke (end to end) tests on a deployed application.
You can check out the <link xl:href="https://github.com/spring-cloud/spring-cloud-pipelines">Spring Cloud Pipelines</link>
project for more information.</simpara>
<section xml:id="_how_to_use_it">
<title>How to use it?</title>
<section xml:id="_stub_runner_server">
<title>Stub Runner Server</title>
<simpara>Just add the</simpara>
<programlisting language="groovy" linenumbering="unnumbered">compile "org.springframework.cloud:spring-cloud-starter-stub-runner"</programlisting>
<simpara>Annotate a class with <literal>@EnableStubRunnerServer</literal>, build a fat-jar and you&#8217;re ready to go!</simpara>
<simpara>For the properties check the <emphasis role="strong">Stub Runner Spring</emphasis> section.</simpara>
</section>
<section xml:id="_spring_cloud_cli">
<title>Spring Cloud CLI</title>
<simpara>Starting from <literal>1.4.0.RELEASE</literal> version of the <link xl:href="https://cloud.spring.io/spring-cloud-cli">Spring Cloud CLI</link>
project you can start Stub Runner Boot by executing <literal>spring cloud stubrunner</literal>.</simpara>
<simpara>In order to pass the configuration just create a <literal>stubrunner.yml</literal> file in the current working directory
or a subdirectory called <literal>config</literal> or in <literal>~/.spring-cloud</literal>. The file could look like this
(example for running stubs installed locally)</simpara>
<formalpara>
<title>stubrunner.yml</title>
<para>
<programlisting language="yml" linenumbering="unnumbered">stubrunner:
  workOffline: true
  ids:
    - com.example:beer-api-producer:+:9876</programlisting>
</para>
</formalpara>
<simpara>and then just call <literal>spring cloud stubrunner</literal> from your terminal window to start
the Stub Runner server. It will be available at port <literal>8750</literal>.</simpara>
</section>
</section>
<section xml:id="_endpoints">
<title>Endpoints</title>
<section xml:id="_http">
<title>HTTP</title>
<itemizedlist>
<listitem>
<simpara>GET <literal>/stubs</literal> - returns a list of all running stubs in <literal>ivy:integer</literal> notation</simpara>
</listitem>
<listitem>
<simpara>GET <literal>/stubs/{ivy}</literal> - returns a port for the given <literal>ivy</literal> notation (when calling the endpoint <literal>ivy</literal> can also be <literal>artifactId</literal> only)</simpara>
</listitem>
</itemizedlist>
</section>
<section xml:id="_messaging">
<title>Messaging</title>
<simpara>For Messaging</simpara>
<itemizedlist>
<listitem>
<simpara>GET <literal>/triggers</literal> - returns a list of all running labels in <literal>ivy : [ label1, label2 &#8230;&#8203;]</literal> notation</simpara>
</listitem>
<listitem>
<simpara>POST <literal>/triggers/{label}</literal> - executes a trigger with <literal>label</literal></simpara>
</listitem>
<listitem>
<simpara>POST <literal>/triggers/{ivy}/{label}</literal> - executes a trigger with <literal>label</literal> for the given <literal>ivy</literal> notation (when calling the endpoint <literal>ivy</literal> can also be <literal>artifactId</literal> only)</simpara>
</listitem>
</itemizedlist>
</section>
</section>
<section xml:id="_example">
<title>Example</title>
<programlisting language="groovy" linenumbering="unnumbered">@ContextConfiguration(classes = StubRunnerBoot, loader = SpringBootContextLoader)
@SpringBootTest(properties = "spring.cloud.zookeeper.enabled=false")
@ActiveProfiles("test")
class StubRunnerBootSpec extends Specification {

	@Autowired StubRunning stubRunning

	def setup() {
		RestAssuredMockMvc.standaloneSetup(new HttpStubsController(stubRunning),
				new TriggerController(stubRunning))
	}

	def 'should return a list of running stub servers in "full ivy:port" notation'() {
		when:
			String response = RestAssuredMockMvc.get('/stubs').body.asString()
		then:
			def root = new JsonSlurper().parseText(response)
			root.'org.springframework.cloud.contract.verifier.stubs:bootService:0.0.1-SNAPSHOT:stubs' instanceof Integer
	}

	def 'should return a port on which a [#stubId] stub is running'() {
		when:
			def response = RestAssuredMockMvc.get("/stubs/${stubId}")
		then:
			response.statusCode == 200
			response.body.as(Integer) &gt; 0
		where:
			stubId &lt;&lt; ['org.springframework.cloud.contract.verifier.stubs:bootService:+:stubs',
					   'org.springframework.cloud.contract.verifier.stubs:bootService:0.0.1-SNAPSHOT:stubs',
					   'org.springframework.cloud.contract.verifier.stubs:bootService:+',
					   'org.springframework.cloud.contract.verifier.stubs:bootService',
					   'bootService']
	}

	def 'should return 404 when missing stub was called'() {
		when:
			def response = RestAssuredMockMvc.get("/stubs/a:b:c:d")
		then:
			response.statusCode == 404
	}

	def 'should return a list of messaging labels that can be triggered when version and classifier are passed'() {
		when:
			String response = RestAssuredMockMvc.get('/triggers').body.asString()
		then:
			def root = new JsonSlurper().parseText(response)
			root.'org.springframework.cloud.contract.verifier.stubs:bootService:0.0.1-SNAPSHOT:stubs'?.containsAll(["delete_book","return_book_1","return_book_2"])
	}

	def 'should trigger a messaging label'() {
		given:
			StubRunning stubRunning = Mock()
			RestAssuredMockMvc.standaloneSetup(new HttpStubsController(stubRunning), new TriggerController(stubRunning))
		when:
			def response = RestAssuredMockMvc.post("/triggers/delete_book")
		then:
			response.statusCode == 200
		and:
			1 * stubRunning.trigger('delete_book')
	}

	def 'should trigger a messaging label for a stub with [#stubId] ivy notation'() {
		given:
			StubRunning stubRunning = Mock()
			RestAssuredMockMvc.standaloneSetup(new HttpStubsController(stubRunning), new TriggerController(stubRunning))
		when:
			def response = RestAssuredMockMvc.post("/triggers/$stubId/delete_book")
		then:
			response.statusCode == 200
		and:
			1 * stubRunning.trigger(stubId, 'delete_book')
		where:
			stubId &lt;&lt; ['org.springframework.cloud.contract.verifier.stubs:bootService:stubs', 'org.springframework.cloud.contract.verifier.stubs:bootService', 'bootService']
	}

	def 'should throw exception when trigger is missing'() {
		when:
			RestAssuredMockMvc.post("/triggers/missing_label")
		then:
			Exception e = thrown(Exception)
			e.message.contains("Exception occurred while trying to return [missing_label] label.")
			e.message.contains("Available labels are")
			e.message.contains("org.springframework.cloud.contract.verifier.stubs:loanIssuance:0.0.1-SNAPSHOT:stubs=[]")
			e.message.contains("org.springframework.cloud.contract.verifier.stubs:bootService:0.0.1-SNAPSHOT:stubs=")
	}

}</programlisting>
</section>
<section xml:id="_stub_runner_boot_with_service_discovery">
<title>Stub Runner Boot with Service Discovery</title>
<simpara>One of the possibilities of using Stub Runner Boot is to use it as a feed of stubs for "smoke-tests". What does it mean?
 Let&#8217;s assume that you don&#8217;t want to deploy 50 microservice to a test environment in order
 to check if your application is working fine. You&#8217;ve already executed a suite of tests during the build process
 but you would also like to ensure that the packaging of your application is fine. What you can do
 is to deploy your application to an environment, start it and run a couple of tests on it to see if
 it&#8217;s working fine. We can call those tests smoke-tests since their idea is to check only a handful
 of testing scenarios.</simpara>
<simpara>The problem with this approach is such that if you&#8217;re doing microservices most likely you&#8217;re
 using a service discovery tool. Stub Runner Boot allows you to solve this issue by starting the
 required stubs and register them in a service discovery tool. Let&#8217;s take a look at an example of
 such a setup with Eureka. Let&#8217;s assume that Eureka was already running.</simpara>
<programlisting language="java" linenumbering="unnumbered">@SpringBootApplication
@EnableStubRunnerServer
@EnableEurekaClient
@AutoConfigureStubRunner
public class StubRunnerBootEurekaExample {

	public static void main(String[] args) {
		SpringApplication.run(StubRunnerBootEurekaExample.class, args);
	}

}</programlisting>
<simpara>As you can see we want to start a Stub Runner Boot server <literal>@EnableStubRunnerServer</literal>, enable Eureka client <literal>@EnableEurekaClient</literal>
and we want to have the stub runner feature turned on <literal>@AutoConfigureStubRunner</literal>.</simpara>
<simpara>Now let&#8217;s assume that we want to start this application so that the stubs get automatically registered.
 We can do it by running the app <literal>java -jar ${SYSTEM_PROPS} stub-runner-boot-eureka-example.jar</literal> where
 <literal>${SYSTEM_PROPS}</literal> would contain the following list of properties</simpara>
<programlisting language="bash" linenumbering="unnumbered">-Dstubrunner.repositoryRoot=https://repo.spring.io/snapshots (1)
-Dstubrunner.cloud.stubbed.discovery.enabled=false (2)
-Dstubrunner.ids=org.springframework.cloud.contract.verifier.stubs:loanIssuance,org.springframework.cloud.contract.verifier.stubs:fraudDetectionServer,org.springframework.cloud.contract.verifier.stubs:bootService (3)
-Dstubrunner.idsToServiceIds.fraudDetectionServer=someNameThatShouldMapFraudDetectionServer (4)

(1) - we tell Stub Runner where all the stubs reside
(2) - we don't want the default behaviour where the discovery service is stubbed. That's why the stub registration will be picked
(3) - we provide a list of stubs to download
(4) - we provide a list of artifactId to serviceId mapping</programlisting>
<simpara>That way your deployed application can send requests to started WireMock servers via the service
discovery. Most likely points 1-3 could be set by default in <literal>application.yml</literal> cause they are not
likely to change. That way you can provide only the list of stubs to download whenever you start
the Stub Runner Boot.</simpara>
</section>
</section>
<section xml:id="_stubs_per_consumer">
<title>Stubs Per Consumer</title>
<simpara>There are cases in which 2 consumers of the same endpoint want to have 2 different responses.</simpara>
<tip>
<simpara>This approach also allows you to immediately know which consumer is using which part of your API.
You can remove part of a response that your API produces and you can see which of your autogenerated tests
fails. If none fails then you can safely delete that part of the response cause nobody is using it.</simpara>
</tip>
<simpara>Let&#8217;s look at the following example for contract defined for the producer called <literal>producer</literal>.
There are 2 consumers: <literal>foo-consumer</literal> and <literal>bar-consumer</literal>.</simpara>
<simpara><emphasis role="strong">Consumer <literal>foo-service</literal></emphasis></simpara>
<programlisting language="groovy" linenumbering="unnumbered">request {
   url '/foo'
   method GET()
}
response {
    status 200
    body(
       foo: "foo"
    }
}</programlisting>
<simpara><emphasis role="strong">Consumer <literal>bar-service</literal></emphasis></simpara>
<programlisting language="groovy" linenumbering="unnumbered">request {
   url '/foo'
   method GET()
}
response {
    status 200
    body(
       bar: "bar"
    }
}</programlisting>
<simpara>You can&#8217;t produce for the same request 2 different responses. That&#8217;s why you can properly package the
contracts and then profit from the <literal>stubsPerConsumer</literal> feature.</simpara>
<simpara>On the producer side the consumers can have a folder that contains contracts related only to them.
By setting the <literal>stubrunner.stubs-per-consumer</literal> flag to <literal>true</literal> we no longer register all stubs but only those that
correspond to the consumer application&#8217;s name. In other words we&#8217;ll scan the path of every stub and
if it contains the subfolder with name of the consumer in the path only then will it get registered.</simpara>
<simpara>On the <literal>foo</literal> producer side the contracts would look like this</simpara>
<programlisting language="bash" linenumbering="unnumbered">.
└── contracts
    ├── bar-consumer
    │   ├── bookReturnedForBar.groovy
    │   └── shouldCallBar.groovy
    └── foo-consumer
        ├── bookReturnedForFoo.groovy
        └── shouldCallFoo.groovy</programlisting>
<simpara>Being the <literal>bar-consumer</literal> consumer you can either set the <literal>spring.application.name</literal> or the <literal>stubrunner.consumer-name</literal> to <literal>bar-consumer</literal>
Or set the test as follows:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@ContextConfiguration(classes = Config, loader = SpringBootContextLoader)
@SpringBootTest(properties = ["spring.application.name=bar-consumer"])
@AutoConfigureStubRunner(ids = "org.springframework.cloud.contract.verifier.stubs:producerWithMultipleConsumers",
		repositoryRoot = "classpath:m2repo/repository/",
		stubsPerConsumer = true)
@DirtiesContext
class StubRunnerStubsPerConsumerSpec extends Specification {
...
}</programlisting>
<simpara>Then only the stubs registered under a path that contains the <literal>bar-consumer</literal> in its name (i.e. those from the
<literal>src/test/resources/contracts/bar-consumer/some/contracts/&#8230;&#8203;</literal> folder) will be allowed to be referenced.</simpara>
<simpara>Or set the consumer name explicitly</simpara>
<programlisting language="groovy" linenumbering="unnumbered">@ContextConfiguration(classes = Config, loader = SpringBootContextLoader)
@SpringBootTest
@AutoConfigureStubRunner(ids = "org.springframework.cloud.contract.verifier.stubs:producerWithMultipleConsumers",
		repositoryRoot = "classpath:m2repo/repository/",
		consumerName = "foo-consumer",
		stubsPerConsumer = true)
@DirtiesContext
class StubRunnerStubsPerConsumerWithConsumerNameSpec extends Specification {
...
}</programlisting>
<simpara>Then only the stubs registered under a path that contains the <literal>foo-consumer</literal> in its name (i.e. those from the
<literal>src/test/resources/contracts/foo-consumer/some/contracts/&#8230;&#8203;</literal> folder) will be allowed to be referenced.</simpara>
<simpara>You can check out <link xl:href="https://github.com/spring-cloud/spring-cloud-contract/issues/224">issue 224</link> for more
information about the reasons behind this change.</simpara>
</section>
<section xml:id="_common">
<title>Common</title>
<section xml:id="_common_properties_for_junit_and_spring">
<title>Common properties for JUnit and Spring</title>
<simpara>Some of the properties that are repetitive can be set using system properties or configuration properties (for Spring). Here are their names with their default values:</simpara>
<informaltable frame="topbot" rowsep="1" colsep="1">
<tgroup cols="3">
<colspec colname="col_1" colwidth="33.3333*"/>
<colspec colname="col_2" colwidth="33.3333*"/>
<colspec colname="col_3" colwidth="33.3334*"/>
<thead>
<row>
<entry align="left" valign="top">Property name</entry>
<entry align="left" valign="top">Default value</entry>
<entry align="left" valign="top">Description</entry>
</row>
</thead>
<tbody>
<row>
<entry align="left" valign="top"><simpara>stubrunner.minPort</simpara></entry>
<entry align="left" valign="top"><simpara>10000</simpara></entry>
<entry align="left" valign="top"><simpara>Minimal value of a port for a started WireMock with stubs</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.maxPort</simpara></entry>
<entry align="left" valign="top"><simpara>15000</simpara></entry>
<entry align="left" valign="top"><simpara>Minimal value of a port for a started WireMock with stubs</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.repositoryRoot</simpara></entry>
<entry align="left" valign="top"></entry>
<entry align="left" valign="top"><simpara>Maven repo url. If blank then will call the local maven repo</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.classifier</simpara></entry>
<entry align="left" valign="top"><simpara>stubs</simpara></entry>
<entry align="left" valign="top"><simpara>Default classifier for the stub artifacts</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.workOffline</simpara></entry>
<entry align="left" valign="top"><simpara>false</simpara></entry>
<entry align="left" valign="top"><simpara>If true then will not contact any remote repositories to download stubs</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.ids</simpara></entry>
<entry align="left" valign="top"></entry>
<entry align="left" valign="top"><simpara>Array of Ivy notation stubs to download</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.username</simpara></entry>
<entry align="left" valign="top"></entry>
<entry align="left" valign="top"><simpara>Optional username to access the tool that stores the JARs with stubs</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.password</simpara></entry>
<entry align="left" valign="top"></entry>
<entry align="left" valign="top"><simpara>Optional password to access the tool that stores the JARs with stubs</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.stubsPerConsumer</simpara></entry>
<entry align="left" valign="top"><simpara>false</simpara></entry>
<entry align="left" valign="top"><simpara>Set to <literal>true</literal> if you want to use different stubs per each consumer instead of registering all stubs for every consumer</simpara></entry>
</row>
<row>
<entry align="left" valign="top"><simpara>stubrunner.consumerName</simpara></entry>
<entry align="left" valign="top"></entry>
<entry align="left" valign="top"><simpara>If you want to use stubs per consumer and want to override the consumer name just change this value</simpara></entry>
</row>
</tbody>
</tgroup>
</informaltable>
</section>
<section xml:id="_stub_runner_stubs_ids">
<title>Stub runner stubs ids</title>
<simpara>You can provide the stubs to download via the <literal>stubrunner.ids</literal> system property. They follow the following pattern:</simpara>
<programlisting language="java" linenumbering="unnumbered">groupId:artifactId:version:classifier:port</programlisting>
<simpara><literal>version</literal>, <literal>classifier</literal> and <literal>port</literal> are optional.</simpara>
<itemizedlist>
<listitem>
<simpara>If you don&#8217;t provide the <literal>port</literal> then a random one will be picked</simpara>
</listitem>
<listitem>
<simpara>If you don&#8217;t provide the <literal>classifier</literal> then the default one will be taken. (NOTE that you can pass an empty classifier like this <literal>groupId:artifactId:version:</literal>)</simpara>
</listitem>
<listitem>
<simpara>If you don&#8217;t provide the <literal>version</literal> then the <literal>+</literal> will be passed and the latest one will be downloaded</simpara>
</listitem>
</itemizedlist>
<simpara>Where <literal>port</literal> means the port of the WireMock server.</simpara>
<important>
<simpara>Starting from version 1.0.4 as a version you can provide a range of versions that you would like
the Stub Runner to take into consideration. You can read more about the <link xl:href="https://wiki.eclipse.org/Aether/New_and_Noteworthy#Version_Ranges">Aether versioning ranges here</link>.</simpara>
</important>
<simpara>Taken from <link xl:href="https://download.eclipse.org/aether/aether-core/0.9.0/apidocs/org/eclipse/aether/util/version/GenericVersionScheme.html">Aether Docs</link>:</simpara>
<blockquote>
<simpara>This scheme accepts versions of any form, interpreting a version as a sequence of numeric and alphabetic segments. The characters '-', '_', and '.' as well as the mere
transitions from digit to letter and vice versa delimit the version segments. Delimiters are treated as equivalent.</simpara>
<simpara>Numeric segments are compared mathematically, alphabetic segments are compared lexicographically and case-insensitively. However, the following qualifier strings are
recognized and treated specially: "alpha" = "a" &lt; "beta" = "b" &lt; "milestone" = "m" &lt; "cr" = "rc" &lt; "snapshot" &lt; "final" = "ga" &lt; "sp". All of those well-known qualifiers
are considered smaller/older than other strings. An empty segment/string is equivalent to 0.</simpara>
<simpara>In addition to the above mentioned qualifiers, the tokens "min" and "max" may be used as final version segment to denote the smallest/greatest version having a given prefix.
For example, "1.2.min" denotes the smallest version in the 1.2 line, "1.2.max" denotes the greatest version in the 1.2 line. A version range of the form "[M.N.*]" is short for "[M.N.min, M.N.max]".</simpara>
<simpara>Numbers and strings are considered incomparable against each other. Where version segments of different kind would collide, comparison will instead assume that the previous
segments are padded with trailing 0 or "ga" segments, respectively, until the kind mismatch is resolved, e.g. "1-alpha" = "1.0.0-alpha" &lt; "1.0.1-ga" = "1.0.1".</simpara>
</blockquote>
</section>
</section>
</chapter>
<chapter xml:id="_stub_runner_for_messaging">
<title>Stub Runner for Messaging</title>
<simpara>Stub Runner has the functionality to run the published stubs in memory. It can integrate with the following frameworks out of the box</simpara>
<itemizedlist>
<listitem>
<simpara>Spring Integration</simpara>
</listitem>
<listitem>
<simpara>Spring Cloud Stream</simpara>
</listitem>
<listitem>
<simpara>Apache Camel</simpara>
</listitem>
<listitem>
<simpara>Spring AMQP</simpara>
</listitem>
</itemizedlist>
<simpara>It also provides points of entry to integrate with any other solution on the market.</simpara>
<important>
<simpara>If you have multiple frameworks on the classpath Stub Runner will need to
define which one should be used. Let&#8217;s assume that you have both AMQP, Spring Cloud Stream and Spring Integration
on the classpath. Then you need to set <literal>stubrunner.stream.enabled=false</literal> and <literal>stubrunner.integration.enabled=false</literal>.
That way the only remaining framework is Spring AMQP.</simpara>
</important>
<section xml:id="_stub_triggering">
<title>Stub triggering</title>
<simpara>To trigger a message it&#8217;s enough to use the <literal>StubTrigger</literal> interface:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.stubrunner;

import java.util.Collection;
import java.util.Map;

public interface StubTrigger {

	/**
	 * Triggers an event by a given label for a given {@code groupid:artifactid} notation. You can use only {@code artifactId} too.
	 *
	 * Feature related to messaging.
	 *
	 * @return true - if managed to run a trigger
	 */
	boolean trigger(String ivyNotation, String labelName);

	/**
	 * Triggers an event by a given label.
	 *
	 * Feature related to messaging.
	 *
	 * @return true - if managed to run a trigger
	 */
	boolean trigger(String labelName);

	/**
	 * Triggers all possible events.
	 *
	 * Feature related to messaging.
	 *
	 * @return true - if managed to run a trigger
	 */
	boolean trigger();

	/**
	 * Returns a mapping of ivy notation of a dependency to all the labels it has.
	 *
	 * Feature related to messaging.
	 */
	Map&lt;String, Collection&lt;String&gt;&gt; labels();
}</programlisting>
<simpara>For convenience the <literal>StubFinder</literal> interface extends <literal>StubTrigger</literal> so it&#8217;s enough to use only one in your tests.</simpara>
<simpara><literal>StubTrigger</literal> gives you the following options to trigger a message:</simpara>
<section xml:id="_trigger_by_label">
<title>Trigger by label</title>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger('return_book_1')</programlisting>
</section>
<section xml:id="_trigger_by_group_and_artifact_ids">
<title>Trigger by group and artifact ids</title>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger('org.springframework.cloud.contract.verifier.stubs:camelService', 'return_book_1')</programlisting>
</section>
<section xml:id="_trigger_by_artifact_ids">
<title>Trigger by artifact ids</title>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger('camelService', 'return_book_1')</programlisting>
</section>
<section xml:id="_trigger_all_messages">
<title>Trigger all messages</title>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger()</programlisting>
</section>
</section>
<section xml:id="_stub_runner_camel">
<title>Stub Runner Camel</title>
<simpara>Spring Cloud Contract Verifier Stub Runner&#8217;s messaging module gives you an easy way to integrate with Apache Camel.
For the provided artifacts it will automatically download the stubs and register the required
routes.</simpara>
<section xml:id="_adding_it_to_the_project">
<title>Adding it to the project</title>
<simpara>It&#8217;s enough to have both Apache Camel and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with <literal>@AutoConfigureStubRunner</literal>.</simpara>
</section>
<section xml:id="_disabling_the_functionality">
<title>Disabling the functionality</title>
<simpara>If you need to disable this functionality just pass <literal>stubrunner.camel.enabled=false</literal> property.</simpara>
</section>
<section xml:id="_examples">
<title>Examples</title>
<section xml:id="_stubs_structure">
<title>Stubs structure</title>
<simpara>Let us assume that we have the following Maven repository with a deployed stubs for the
<literal>camelService</literal> application.</simpara>
<programlisting language="bash" linenumbering="unnumbered">└── .m2
    └── repository
        └── io
            └── codearte
                └── accurest
                    └── stubs
                        └── camelService
                            ├── 0.0.1-SNAPSHOT
                            │   ├── camelService-0.0.1-SNAPSHOT.pom
                            │   ├── camelService-0.0.1-SNAPSHOT-stubs.jar
                            │   └── maven-metadata-local.xml
                            └── maven-metadata-local.xml</programlisting>
<simpara>And the stubs contain the following structure:</simpara>
<programlisting language="bash" linenumbering="unnumbered">├── META-INF
│   └── MANIFEST.MF
└── repository
    ├── accurest
    │   ├── bookDeleted.groovy
    │   ├── bookReturned1.groovy
    │   └── bookReturned2.groovy
    └── mappings</programlisting>
<simpara>Let&#8217;s consider the following contracts (let' number it with <emphasis role="strong">1</emphasis>):</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'return_book_1'
	input {
		triggeredBy('bookReturnedTriggered()')
	}
	outputMessage {
		sentTo('jms:output')
		body('''{ "bookName" : "foo" }''')
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
<simpara>and number <emphasis role="strong">2</emphasis></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'return_book_2'
	input {
		messageFrom('jms:input')
		messageBody([
				bookName: 'foo'
		])
		messageHeaders {
			header('sample', 'header')
		}
	}
	outputMessage {
		sentTo('jms:output')
		body([
				bookName: 'foo'
		])
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
</section>
<section xml:id="_scenario_1_no_input_message_2">
<title>Scenario 1 (no input message)</title>
<simpara>So as to trigger a message via the <literal>return_book_1</literal> label we&#8217;ll use the <literal>StubTigger</literal> interface as follows</simpara>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger('return_book_1')</programlisting>
<simpara>Next we&#8217;ll want to listen to the output of the message sent to <literal>jms:output</literal></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Exchange receivedMessage = camelContext.createConsumerTemplate().receive('jms:output', 5000)</programlisting>
<simpara>And the received message would pass the following assertions</simpara>
<programlisting language="groovy" linenumbering="unnumbered">receivedMessage != null
assertThatBodyContainsBookNameFoo(receivedMessage.in.body)
receivedMessage.in.headers.get('BOOK-NAME') == 'foo'</programlisting>
</section>
<section xml:id="_scenario_2_output_triggered_by_input_2">
<title>Scenario 2 (output triggered by input)</title>
<simpara>Since the route is set for you it&#8217;s enough to just send a message to the <literal>jms:output</literal> destination.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">camelContext.createProducerTemplate().sendBodyAndHeaders('jms:input', new BookReturned('foo'), [sample: 'header'])</programlisting>
<simpara>Next we&#8217;ll want to listen to the output of the message sent to <literal>jms:output</literal></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Exchange receivedMessage = camelContext.createConsumerTemplate().receive('jms:output', 5000)</programlisting>
<simpara>And the received message would pass the following assertions</simpara>
<programlisting language="groovy" linenumbering="unnumbered">receivedMessage != null
assertThatBodyContainsBookNameFoo(receivedMessage.in.body)
receivedMessage.in.headers.get('BOOK-NAME') == 'foo'</programlisting>
</section>
<section xml:id="_scenario_3_input_with_no_output">
<title>Scenario 3 (input with no output)</title>
<simpara>Since the route is set for you it&#8217;s enough to just send a message to the <literal>jms:output</literal> destination.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">camelContext.createProducerTemplate().sendBodyAndHeaders('jms:delete', new BookReturned('foo'), [sample: 'header'])</programlisting>
</section>
</section>
</section>
<section xml:id="_stub_runner_integration">
<title>Stub Runner Integration</title>
<simpara>Spring Cloud Contract Verifier Stub Runner&#8217;s messaging module gives you an easy way to integrate with Spring Integration.
For the provided artifacts it will automatically download the stubs and register the required
routes.</simpara>
<section xml:id="_adding_it_to_the_project_2">
<title>Adding it to the project</title>
<simpara>It&#8217;s enough to have both Spring Integration and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with <literal>@AutoConfigureStubRunner</literal>.</simpara>
</section>
<section xml:id="_disabling_the_functionality_2">
<title>Disabling the functionality</title>
<simpara>If you need to disable this functionality just pass <literal>stubrunner.integration.enabled=false</literal> property.</simpara>
</section>
<section xml:id="_examples_2">
<title>Examples</title>
<section xml:id="_stubs_structure_2">
<title>Stubs structure</title>
<simpara>Let us assume that we have the following Maven repository with a deployed stubs for the
<literal>integrationService</literal> application.</simpara>
<programlisting language="bash" linenumbering="unnumbered">└── .m2
    └── repository
        └── io
            └── codearte
                └── accurest
                    └── stubs
                        └── integrationService
                            ├── 0.0.1-SNAPSHOT
                            │   ├── integrationService-0.0.1-SNAPSHOT.pom
                            │   ├── integrationService-0.0.1-SNAPSHOT-stubs.jar
                            │   └── maven-metadata-local.xml
                            └── maven-metadata-local.xml</programlisting>
<simpara>And the stubs contain the following structure:</simpara>
<programlisting language="bash" linenumbering="unnumbered">├── META-INF
│   └── MANIFEST.MF
└── repository
    ├── accurest
    │   ├── bookDeleted.groovy
    │   ├── bookReturned1.groovy
    │   └── bookReturned2.groovy
    └── mappings</programlisting>
<simpara>Let&#8217;s consider the following contracts (let' number it with <emphasis role="strong">1</emphasis>):</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'return_book_1'
	input {
		triggeredBy('bookReturnedTriggered()')
	}
	outputMessage {
		sentTo('output')
		body('''{ "bookName" : "foo" }''')
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
<simpara>and number <emphasis role="strong">2</emphasis></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'return_book_2'
	input {
		messageFrom('input')
		messageBody([
				bookName: 'foo'
		])
		messageHeaders {
			header('sample', 'header')
		}
	}
	outputMessage {
		sentTo('output')
		body([
				bookName: 'foo'
		])
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
<simpara>and the following Spring Integration Route:</simpara>
<programlisting language="xml" linenumbering="unnumbered">&lt;?xml version="1.0" encoding="UTF-8"?&gt;
&lt;beans:beans xmlns="http://www.springframework.org/schema/integration"
			 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
			 xmlns:beans="http://www.springframework.org/schema/beans"
			 xsi:schemaLocation="http://www.springframework.org/schema/beans
			https://www.springframework.org/schema/beans/spring-beans.xsd
			http://www.springframework.org/schema/integration
			https://www.springframework.org/schema/integration/spring-integration.xsd"&gt;


	&lt;!-- REQUIRED FOR TESTING --&gt;
	&lt;bridge input-channel="output"
			output-channel="outputTest"/&gt;

	&lt;channel id="outputTest"&gt;
		&lt;queue/&gt;
	&lt;/channel&gt;

&lt;/beans:beans&gt;</programlisting>
</section>
<section xml:id="_scenario_1_no_input_message_3">
<title>Scenario 1 (no input message)</title>
<simpara>So as to trigger a message via the <literal>return_book_1</literal> label we&#8217;ll use the <literal>StubTigger</literal> interface as follows</simpara>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger('return_book_1')</programlisting>
<simpara>Next we&#8217;ll want to listen to the output of the message sent to <literal>output</literal></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Message&lt;?&gt; receivedMessage = messaging.receive('outputTest')</programlisting>
<simpara>And the received message would pass the following assertions</simpara>
<programlisting language="groovy" linenumbering="unnumbered">receivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'</programlisting>
</section>
<section xml:id="_scenario_2_output_triggered_by_input_3">
<title>Scenario 2 (output triggered by input)</title>
<simpara>Since the route is set for you it&#8217;s enough to just send a message to the <literal>output</literal> destination.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">messaging.send(new BookReturned('foo'), [sample: 'header'], 'input')</programlisting>
<simpara>Next we&#8217;ll want to listen to the output of the message sent to <literal>output</literal></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Message&lt;?&gt; receivedMessage = messaging.receive('outputTest')</programlisting>
<simpara>And the received message would pass the following assertions</simpara>
<programlisting language="groovy" linenumbering="unnumbered">receivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'</programlisting>
</section>
<section xml:id="_scenario_3_input_with_no_output_2">
<title>Scenario 3 (input with no output)</title>
<simpara>Since the route is set for you it&#8217;s enough to just send a message to the <literal>input</literal> destination.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">messaging.send(new BookReturned('foo'), [sample: 'header'], 'delete')</programlisting>
</section>
</section>
</section>
<section xml:id="_stub_runner_stream">
<title>Stub Runner Stream</title>
<simpara>Spring Cloud Contract Verifier Stub Runner&#8217;s messaging module gives you an easy way to integrate with Spring Stream.
For the provided artifacts it will automatically download the stubs and register the required
routes.</simpara>
<warning>
<simpara>In Stub Runner&#8217;s integration with Stream the <literal>messageFrom</literal> or <literal>sentTo</literal> Strings are resolved
first as a <literal>destination</literal> of a channel, and then if there is no such <literal>destination</literal> it&#8217;s resolved as a
channel name.</simpara>
</warning>
<important>
<simpara>If you want to use Spring Cloud Stream remember to add a
<literal>org.springframework.cloud:spring-cloud-stream-test-support</literal> dependency.</simpara>
</important>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
    &lt;artifactId&gt;spring-cloud-stream-test-support&lt;/artifactId&gt;
    &lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">testCompile "org.springframework.cloud:spring-cloud-stream-test-support"</programlisting>
</para>
</formalpara>
<section xml:id="_adding_it_to_the_project_3">
<title>Adding it to the project</title>
<simpara>It&#8217;s enough to have both Spring Cloud Stream and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with <literal>@AutoConfigureStubRunner</literal>.</simpara>
</section>
<section xml:id="_disabling_the_functionality_3">
<title>Disabling the functionality</title>
<simpara>If you need to disable this functionality just pass <literal>stubrunner.stream.enabled=false</literal> property.</simpara>
</section>
<section xml:id="_examples_3">
<title>Examples</title>
<section xml:id="_stubs_structure_3">
<title>Stubs structure</title>
<simpara>Let us assume that we have the following Maven repository with a deployed stubs for the
<literal>streamService</literal> application.</simpara>
<programlisting language="bash" linenumbering="unnumbered">└── .m2
    └── repository
        └── io
            └── codearte
                └── accurest
                    └── stubs
                        └── streamService
                            ├── 0.0.1-SNAPSHOT
                            │   ├── streamService-0.0.1-SNAPSHOT.pom
                            │   ├── streamService-0.0.1-SNAPSHOT-stubs.jar
                            │   └── maven-metadata-local.xml
                            └── maven-metadata-local.xml</programlisting>
<simpara>And the stubs contain the following structure:</simpara>
<programlisting language="bash" linenumbering="unnumbered">├── META-INF
│   └── MANIFEST.MF
└── repository
    ├── accurest
    │   ├── bookDeleted.groovy
    │   ├── bookReturned1.groovy
    │   └── bookReturned2.groovy
    └── mappings</programlisting>
<simpara>Let&#8217;s consider the following contracts (let' number it with <emphasis role="strong">1</emphasis>):</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'return_book_1'
	input { triggeredBy('bookReturnedTriggered()') }
	outputMessage {
		sentTo('returnBook')
		body('''{ "bookName" : "foo" }''')
		headers { header('BOOK-NAME', 'foo') }
	}
}</programlisting>
<simpara>and number <emphasis role="strong">2</emphasis></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'return_book_2'
	input {
		messageFrom('bookStorage')
		messageBody([
			bookName: 'foo'
		])
		messageHeaders { header('sample', 'header') }
	}
	outputMessage {
		sentTo('returnBook')
		body([
			bookName: 'foo'
		])
		headers { header('BOOK-NAME', 'foo') }
	}
}</programlisting>
<simpara>and the following Spring configuration:</simpara>
<programlisting language="yaml" linenumbering="unnumbered">stubrunner.repositoryRoot: classpath:m2repo/repository/
stubrunner.ids: org.springframework.cloud.contract.verifier.stubs:streamService:0.0.1-SNAPSHOT:stubs

spring:
  cloud:
    stream:
      bindings:
        output:
          destination: returnBook
        input:
          destination: bookStorage

server:
  port: 0

debug: true</programlisting>
</section>
<section xml:id="_scenario_1_no_input_message_4">
<title>Scenario 1 (no input message)</title>
<simpara>So as to trigger a message via the <literal>return_book_1</literal> label we&#8217;ll use the <literal>StubTrigger</literal> interface as follows</simpara>
<programlisting language="groovy" linenumbering="unnumbered">stubFinder.trigger('return_book_1')</programlisting>
<simpara>Next we&#8217;ll want to listen to the output of the message sent to a channel whose <literal>destination</literal> is <literal>returnBook</literal></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Message&lt;?&gt; receivedMessage = messaging.receive('returnBook')</programlisting>
<simpara>And the received message would pass the following assertions</simpara>
<programlisting language="groovy" linenumbering="unnumbered">receivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'</programlisting>
</section>
<section xml:id="_scenario_2_output_triggered_by_input_4">
<title>Scenario 2 (output triggered by input)</title>
<simpara>Since the route is set for you it&#8217;s enough to just send a message to the <literal>bookStorage</literal> <literal>destination</literal>.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">messaging.send(new BookReturned('foo'), [sample: 'header'], 'bookStorage')</programlisting>
<simpara>Next we&#8217;ll want to listen to the output of the message sent to <literal>returnBook</literal></simpara>
<programlisting language="groovy" linenumbering="unnumbered">Message&lt;?&gt; receivedMessage = messaging.receive('returnBook')</programlisting>
<simpara>And the received message would pass the following assertions</simpara>
<programlisting language="groovy" linenumbering="unnumbered">receivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'</programlisting>
</section>
<section xml:id="_scenario_3_input_with_no_output_3">
<title>Scenario 3 (input with no output)</title>
<simpara>Since the route is set for you it&#8217;s enough to just send a message to the <literal>output</literal> destination.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">messaging.send(new BookReturned('foo'), [sample: 'header'], 'delete')</programlisting>
</section>
</section>
</section>
<section xml:id="_stub_runner_spring_amqp">
<title>Stub Runner Spring AMQP</title>
<simpara>Spring Cloud Contract Verifier Stub Runner&#8217;s messaging module provides an easy way to integrate with Spring AMQP&#8217;s Rabbit Template.
For the provided artifacts it will automatically download the stubs and register the required
routes.</simpara>
<simpara>The integration tries to work standalone, that is without interaction with a running RabbitMQ message broker.
It expects a <literal>RabbitTemplate</literal> on the application context and uses it as a spring boot test <literal>@SpyBean</literal>.
Thus it can use the mockito spy functionality to verify and introspect messages sent by the application.</simpara>
<simpara>On the message consumer side, it considers all <literal>@RabbitListener</literal> annotated endpoints as well as all `SimpleMessageListenerContainer`s on the application context.</simpara>
<simpara>As messages are usually sent to exchanges in AMQP the message contract contains the exchange name as the destination.
Message listeners on the other side are bound to queues. Bindings connect an exchange to a queue.
If message contracts are triggered the Spring AMQP stub runner integration will look for bindings on the application context that match this exchange.
Then it collects the queues from the Spring exchanges and tries to find messages listeners bound to these queues.
The message is triggered to all matching message listeners.</simpara>
<section xml:id="_adding_it_to_the_project_4">
<title>Adding it to the project</title>
<simpara>It&#8217;s enough to have both Spring AMQP and Spring Cloud Contract Stub Runner on the classpath and set the property <literal>stubrunner.amqp.enabled=true</literal>.
Remember to annotate your test class with <literal>@AutoConfigureStubRunner</literal>.</simpara>
<important>
<simpara>If you already have Stream and Integration on the classpath you need
to disable them explicitly via <literal>stubrunner.stream.enabled=false</literal> and <literal>stubrunner.integration.enabled=false</literal>
properties</simpara>
</important>
</section>
<section xml:id="_examples_4">
<title>Examples</title>
<section xml:id="_stubs_structure_4">
<title>Stubs structure</title>
<simpara>Let us assume that we have the following Maven repository with a deployed stubs for the
<literal>spring-cloud-contract-amqp-test</literal> application.</simpara>
<programlisting language="bash" linenumbering="unnumbered">└── .m2
    └── repository
        └── com
            └── example
                └── spring-cloud-contract-amqp-test
                    ├── 0.4.0-SNAPSHOT
                    │   ├── spring-cloud-contract-amqp-test-0.4.0-SNAPSHOT.pom
                    │   ├── spring-cloud-contract-amqp-test-0.4.0-SNAPSHOT-stubs.jar
                    │   └── maven-metadata-local.xml
                    └── maven-metadata-local.xml</programlisting>
<simpara>And the stubs contain the following structure:</simpara>
<programlisting language="bash" linenumbering="unnumbered">├── META-INF
│   └── MANIFEST.MF
└── contracts
    └── shouldProduceValidPersonData.groovy</programlisting>
<simpara>Let&#8217;s consider the following contract:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
    // Human readable description
    description 'Should produce valid person data'
    // Label by means of which the output message can be triggered
    label 'contract-test.person.created.event'
    // input to the contract
    input {
        // the contract will be triggered by a method
        triggeredBy('createPerson()')
    }
    // output message of the contract
    outputMessage {
        // destination to which the output message will be sent
        sentTo 'contract-test.exchange'
        headers {
            header('contentType': 'application/json')
            header('__TypeId__': 'org.springframework.cloud.contract.stubrunner.messaging.amqp.Person')
        }
        // the body of the output message
        body ([
                id: $(consumer(9), producer(regex("[0-9]+"))),
                name: "me"
        ])
    }
}</programlisting>
<simpara>and the following Spring configuration:</simpara>
<programlisting language="yaml" linenumbering="unnumbered">stubrunner:
  repositoryRoot: classpath:m2repo/repository/
  ids: org.springframework.cloud.contract.verifier.stubs.amqp:spring-cloud-contract-amqp-test:0.4.0-SNAPSHOT:stubs
  amqp:
    enabled: true
server:
  port: 0</programlisting>
</section>
<section xml:id="_triggering_the_message">
<title>Triggering the message</title>
<simpara>So to trigger a message using the contract above we&#8217;ll use the <literal>StubTrigger</literal> interface as follows.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">stubTrigger.trigger("contract-test.person.created.event")</programlisting>
<simpara>The message has the destination <literal>contract-test.exchange</literal> so the Spring AMQP stub runner integration looks for bindings related to this exchange.</simpara>
<programlisting language="java" linenumbering="unnumbered">@Bean
public Binding binding() {
	return BindingBuilder.bind(new Queue("test.queue")).to(new DirectExchange("contract-test.exchange")).with("#");
}</programlisting>
<simpara>The binding definition binds the queue <literal>test.queue</literal>.
So the following listener definition is a match and is invoked with the contract message.</simpara>
<programlisting language="java" linenumbering="unnumbered">@Bean
public SimpleMessageListenerContainer simpleMessageListenerContainer(ConnectionFactory connectionFactory,
																		MessageListenerAdapter listenerAdapter) {
	SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
	container.setConnectionFactory(connectionFactory);
	container.setQueueNames("test.queue");
	container.setMessageListener(listenerAdapter);

	return container;
}</programlisting>
<simpara>Also, the following annotated listener represents a match and would be invoked.</simpara>
<programlisting language="java" linenumbering="unnumbered">@RabbitListener(bindings = @QueueBinding(
		value = @Queue(value = "test.queue"),
		exchange = @Exchange(value = "contract-test.exchange", ignoreDeclarationExceptions = "true")))
public void handlePerson(Person person) {
	this.person = person;
}</programlisting>
<note>
<simpara>The message is directly handed over to the <literal>onMessage</literal> method of the <literal>MessageListener</literal> associated with the matching <literal>SimpleMessageListenerContainer</literal>.</simpara>
</note>
</section>
<section xml:id="_spring_amqp_test_configuration">
<title>Spring AMQP Test Configuration</title>
<simpara>In order to avoid that Spring AMQP is trying to connect to a running broker during our tests we configure a mock <literal>ConnectionFactory</literal>.</simpara>
<simpara>To disable the mocked ConnectionFactory set the property <literal>stubrunner.amqp.mockConnection=false</literal></simpara>
<programlisting language="yaml" linenumbering="unnumbered">stubrunner:
  amqp:
    mockConnection: false</programlisting>
</section>
</section>
</section>
</chapter>
<chapter xml:id="_contract_dsl">
<title>Contract DSL</title>
<important>
<simpara>Remember that, inside the contract file, you have to provide the fully
qualified name to the <literal>Contract</literal> class and <literal>make</literal> static imports, such as
<literal>org.springframework.cloud.spec.Contract.make { &#8230;&#8203; }</literal>. You can also provide an import to
the <literal>Contract</literal> class: <literal>import org.springframework.cloud.spec.Contract</literal> and then call
<literal>Contract.make { &#8230;&#8203; }</literal>.</simpara>
</important>
<simpara>Contract DSL is written in Groovy, but do not be alarmed if you have not used Groovy
before. Knowledge of the language is not really needed, as the Contract DSL uses only a
tiny subset of it (only literals, method calls and closures). Also, the DSL is statically
typed, to make it programmer-readable without any knowledge of the DSL itself.</simpara>
<tip>
<simpara>Spring Cloud Contract supports defining multiple contracts in a single file.</simpara>
</tip>
<simpara>The Contract is present in the <literal>spring-cloud-contract-spec</literal> module of the
<link xl:href="https://github.com/spring-cloud/spring-cloud-contract/tree/master/spring-cloud-contract-verifier">Spring
Cloud Contract Verifier repository</link>.</simpara>
<simpara>The following is a complete example of a contract definition:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		method 'PUT'
		url '/api/12'
		headers {
			header 'Content-Type': 'application/vnd.org.springframework.cloud.contract.verifier.twitter-places-analyzer.v1+json'
		}
		body '''\
		[{
			"created_at": "Sat Jul 26 09:38:57 +0000 2014",
			"id": 492967299297845248,
			"id_str": "492967299297845248",
			"text": "Gonna see you at Warsaw",
			"place":
			{
				"attributes":{},
				"bounding_box":
				{
					"coordinates":
						[[
							[-77.119759,38.791645],
							[-76.909393,38.791645],
							[-76.909393,38.995548],
							[-77.119759,38.995548]
						]],
					"type":"Polygon"
				},
				"country":"United States",
				"country_code":"US",
				"full_name":"Washington, DC",
				"id":"01fbe706f872cb32",
				"name":"Washington",
				"place_type":"city",
				"url": "https://api.twitter.com/1/geo/id/01fbe706f872cb32.json"
			}
		}]
	'''
	}
	response {
		status 200
	}
}</programlisting>
<note>
<simpara>The preceding example does not contain all the features of the DSL appear. The
remainder of this section describes the other features.</simpara>
</note>
<simpara>You can compile Contracts to WireMock stubs mapping using standalone maven command:
<literal>mvn org.springframework.cloud:spring-cloud-contract-maven-plugin:convert</literal></simpara>
<section xml:id="_limitations_2">
<title>Limitations</title>
<warning>
<simpara>Spring Cloud Contract Verifier does not properly support XML. Please use JSON or
help us implement this feature.</simpara>
</warning>
<warning>
<simpara>The support for verifying the size of JSON arrays is experimental. If you want
to turn it on, please set the value of the following system property to <literal>true</literal>:
<literal>spring.cloud.contract.verifier.assert.size</literal>. By default, this feature is set to <literal>false</literal>.
You can also provide the <literal>assertJsonSize</literal> property in the plugin configuration.</simpara>
</warning>
<warning>
<simpara>Because JSON structure can have any form, it can be impossible to parse it
properly when using the <literal>value(consumer(&#8230;&#8203;), producer(&#8230;&#8203;))</literal> notation in <literal>GString</literal>. That
is why you should use the Groovy Map notation.</simpara>
</warning>
</section>
<section xml:id="_common_top_level_elements">
<title>Common Top-Level elements</title>
<simpara>The following sections describe the most common top-level elements:</simpara>
<itemizedlist>
<listitem>
<simpara><xref linkend="contract-dsl-description"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-name"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-ignoring-contracts"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-passing-values-from-files"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-http-top-level-elements"/></simpara>
</listitem>
</itemizedlist>
<section xml:id="contract-dsl-description">
<title>Description</title>
<simpara>You can add a <literal>description</literal> to your contract. The description is arbitrary text. The
following code shows an example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">		org.springframework.cloud.contract.spec.Contract.make {
			description('''
given:
	An input
when:
	Sth happens
then:
	Output
''')
		}</programlisting>
</section>
<section xml:id="contract-dsl-name">
<title>Name</title>
<simpara>You can provide a name for your contract. Assume that you provided the following name:
<literal>should register a user</literal>. If you do so, the name of the autogenerated test is
<literal>validate_should_register_a_user</literal>. Also, the name of the stub in a WireMock stub is
<literal>should_register_a_user.json</literal>.</simpara>
<important>
<simpara>You must ensure that the name does not contain any characters that make the
generated test not compile. Also, remember that, if you provide the same name for
multiple contracts, your autogenerated tests fail to compile and your generated stubs
override each other.</simpara>
</important>
</section>
<section xml:id="contract-dsl-ignoring-contracts">
<title>Ignoring Contracts</title>
<simpara>If you want to ignore a contract, you can either set a value of ignored contracts in the
plugin configuration or set the <literal>ignored</literal> property on the contract itself:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	ignored()
}</programlisting>
</section>
<section xml:id="contract-dsl-http-top-level-elements">
<title>HTTP Top-Level Elements</title>
<simpara>The following methods can be called in the top-level closure of a contract definition.
<literal>request</literal> and <literal>response</literal> are mandatory. <literal>priority</literal> is optional.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	// Definition of HTTP request part of the contract
	// (this can be a valid request or invalid depending
	// on type of contract being specified).
	request {
		//...
	}

	// Definition of HTTP response part of the contract
	// (a service implementing this contract should respond
	// with following response after receiving request
	// specified in "request" part above).
	response {
		//...
	}

	// Contract priority, which can be used for overriding
	// contracts (1 is highest). Priority is optional.
	priority 1
}</programlisting>
</section>
</section>
<section xml:id="_request">
<title>Request</title>
<simpara>The HTTP protocol requires only <emphasis role="strong">method and address</emphasis> to be specified in a request. The
same information is mandatory in request definition of the Contract.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		// HTTP request method (GET/POST/PUT/DELETE).
		method 'GET'

		// Path component of request URL is specified as follows.
		urlPath('/users')
	}

	response {
		//...
	}
}</programlisting>
<simpara>It is possible to specify an absolute rather than relative <literal>url</literal>, but using <literal>urlPath</literal> is
the recommended way, as doing so makes the tests <emphasis role="strong">host-independent</emphasis>.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		method 'GET'

		// Specifying `url` and `urlPath` in one contract is illegal.
		url('http://localhost:8888/users')
	}

	response {
		//...
	}
}</programlisting>
<simpara><literal>request</literal> may contain <emphasis role="strong">query parameters</emphasis>, which are specified in a closure nested in a
call to <literal>urlPath</literal> or <literal>url</literal>.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		//...

		urlPath('/users') {

			// Each parameter is specified in form
			// `'paramName' : paramValue` where parameter value
			// may be a simple literal or one of matcher functions,
			// all of which are used in this example.
			queryParameters {

				// If a simple literal is used as value
				// default matcher function is used (equalTo)
				parameter 'limit': 100

				// `equalTo` function simply compares passed value
				// using identity operator (==).
				parameter 'filter': equalTo("email")

				// `containing` function matches strings
				// that contains passed substring.
				parameter 'gender': value(consumer(containing("[mf]")), producer('mf'))

				// `matching` function tests parameter
				// against passed regular expression.
				parameter 'offset': value(consumer(matching("[0-9]+")), producer(123))

				// `notMatching` functions tests if parameter
				// does not match passed regular expression.
				parameter 'loginStartsWith': value(consumer(notMatching(".{0,2}")), producer(3))
			}
		}

		//...
	}

	response {
		//...
	}
}</programlisting>
<simpara><literal>request</literal> may contain additional <emphasis role="strong">request headers</emphasis>, as shown in the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		//...

		// Each header is added in form `'Header-Name' : 'Header-Value'`.
		// there are also some helper methods
		headers {
			header 'key': 'value'
			contentType(applicationJson())
		}

		//...
	}

	response {
		//...
	}
}</programlisting>
<simpara><literal>request</literal> may contain a <emphasis role="strong">request body</emphasis>, as shown in the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		//...

		// Currently only JSON format of request body is supported.
		// Format will be determined from a header or body's content.
		body '''{ "login" : "john", "name": "John The Contract" }'''
	}

	response {
		//...
	}
}</programlisting>
<simpara><literal>request</literal> may contain <emphasis role="strong">multipart</emphasis> elements. To include multipart elements, call the
<literal>multipart()</literal> method, as shown in the following example</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract contractDsl = org.springframework.cloud.contract.spec.Contract.make {
	request {
		method "PUT"
		url "/multipart"
		headers {
			contentType('multipart/form-data;boundary=AaB03x')
		}
		multipart(
				// key (parameter name), value (parameter value) pair
				formParameter: $(c(regex('".+"')), p('"formParameterValue"')),
				someBooleanParameter: $(c(regex(anyBoolean())), p('true')),
				// a named parameter (e.g. with `file` name) that represents file with
				// `name` and `content`. You can also call `named("fileName", "fileContent")`
				file: named(
						// name of the file
						name: $(c(regex(nonEmpty())), p('filename.csv')),
						// content of the file
						content: $(c(regex(nonEmpty())), p('file content')))
		)
	}
	response {
		status 200
	}
}</programlisting>
<simpara>In the preceding example, we define parameters in either of two ways:</simpara>
<itemizedlist>
<listitem>
<simpara>Directly, by using the map notation, where the value can be a dynamic property (such as
<literal>formParameter: $(consumer(&#8230;&#8203;), producer(&#8230;&#8203;))</literal>).</simpara>
</listitem>
<listitem>
<simpara>By using the <literal>named(&#8230;&#8203;)</literal> method that lets you set a named parameter. A named parameter
can set a <literal>name</literal> and <literal>content</literal>. You can call it either via a method with two  arguments,
such as <literal>named("fileName", "fileContent")</literal>, or via a map notation, such as
<literal>named(name: "fileName", content: "fileContent")</literal>.</simpara>
</listitem>
</itemizedlist>
<simpara>From this contract, the generated test is as follows:</simpara>
<programlisting language="java" linenumbering="unnumbered">// given:
 MockMvcRequestSpecification request = given()
   .header("Content-Type", "multipart/form-data;boundary=AaB03x")
   .param("formParameter", "\"formParameterValue\"")
   .param("someBooleanParameter", "true")
   .multiPart("file", "filename.csv", "file content".getBytes());

// when:
 ResponseOptions response = given().spec(request)
   .put("/multipart");

// then:
 assertThat(response.statusCode()).isEqualTo(200);</programlisting>
<simpara>The WireMock stub is as follows:</simpara>
<programlisting language="json" linenumbering="unnumbered">			'''
{
  "request" : {
	"url" : "/multipart",
	"method" : "PUT",
	"headers" : {
	  "Content-Type" : {
		"matches" : "multipart/form-data;boundary=AaB03x.*"
	  }
	},
	"bodyPatterns" : [ {
		"matches" : ".*--(.*)\\r\\nContent-Disposition: form-data; name=\\"formParameter\\"\\r\\n(Content-Type: .*\\r\\n)?(Content-Length: \\\\d+\\r\\n)?\\r\\n\\".+\\"\\r\\n--\\\\1.*"
  		}, {
    			"matches" : ".*--(.*)\\r\\nContent-Disposition: form-data; name=\\"someBooleanParameter\\"\\r\\n(Content-Type: .*\\r\\n)?(Content-Length: \\\\d+\\r\\n)?\\r\\n(true|false)\\r\\n--\\\\1.*"
  		}, {
	  "matches" : ".*--(.*)\\r\\nContent-Disposition: form-data; name=\\"file\\"; filename=\\"[\\\\S\\\\s]+\\"\\r\\n(Content-Type: .*\\r\\n)?(Content-Length: \\\\d+\\r\\n)?\\r\\n[\\\\S\\\\s]+\\r\\n--\\\\1.*"
	} ]
  },
  "response" : {
	"status" : 200,
	"transformers" : [ "response-template" ]
  }
}
	'''</programlisting>
</section>
<section xml:id="_response">
<title>Response</title>
<simpara>The response must contain an <emphasis role="strong">HTTP status code</emphasis> and may contain other information. The
following code shows an example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		//...
	}
	response {
		// Status code sent by the server
		// in response to request specified above.
		status 200
	}
}</programlisting>
<simpara>Besides status, the response may contain <emphasis role="strong">headers</emphasis> and a <emphasis role="strong">body</emphasis>, both of which are
specified the same way as in the request (see the previous paragraph).</simpara>
</section>
<section xml:id="_dynamic_properties">
<title>Dynamic properties</title>
<simpara>The contract can contain some dynamic properties: timestamps, IDs, and so on. You do not
want to force the consumers to stub their clocks to always return the same value of time
so that it gets matched by the stub. You can provide the dynamic parts in your contracts
in two ways: pass them directly in the body or set them in separate sections called
<literal>testMatchers</literal> and <literal>stubMatchers</literal>.</simpara>
<section xml:id="_dynamic_properties_inside_the_body">
<title>Dynamic properties inside the body</title>
<simpara>You can set the properties inside the body either with the <literal>value</literal> method or, if you use
the Groovy map notation, with <literal>$()</literal>. The following example shows how to set dynamic
properties with the value method:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">value(consumer(...), producer(...))
value(c(...), p(...))
value(stub(...), test(...))
value(client(...), server(...))</programlisting>
<simpara>The following example shows how to set dynamic properties with <literal>$()</literal>:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">$(consumer(...), producer(...))
$(c(...), p(...))
$(stub(...), test(...))
$(client(...), server(...))</programlisting>
<simpara>Both approaches work equally well. <literal>stub</literal> and <literal>client</literal> methods are aliases over the <literal>consumer</literal>
method. Subsequent sections take a closer look at what you can do with those values.</simpara>
</section>
<section xml:id="_regular_expressions">
<title>Regular expressions</title>
<simpara>You can use regular expressions to write your requests in Contract DSL. Doing so is
particularly useful when you want to indicate that a given response should be provided
for requests that follow a given pattern. Also, you can use regular expressions when you
need to use patterns and not exact values both for your test and your server side tests.</simpara>
<simpara>The following example shows how to use regular expressions to write a request:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		method('GET')
		url $(consumer(~/\/[0-9]{2}/), producer('/12'))
	}
	response {
		status 200
		body(
				id: $(anyNumber()),
				surname: $(
						consumer('Kowalsky'),
						producer(regex('[a-zA-Z]+'))
				),
				name: 'Jan',
				created: $(consumer('2014-02-02 12:23:43'), producer(execute('currentDate(it)'))),
				correlationId: value(consumer('5d1f9fef-e0dc-4f3d-a7e4-72d2220dd827'),
						producer(regex('[a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}'))
				)
		)
		headers {
			header 'Content-Type': 'text/plain'
		}
	}
}</programlisting>
<simpara>You can also provide only one side of the communication with a regular expression. If you
do so, then the contract engine automatically provides the generated string that matches
the provided regular expression. The following code shows an example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		method 'PUT'
		url value(consumer(regex('/foo/[0-9]{5}')))
		body([
			requestElement: $(consumer(regex('[0-9]{5}')))
		])
		headers {
			header('header', $(consumer(regex('application\\/vnd\\.fraud\\.v1\\+json;.*'))))
		}
	}
	response {
		status 200
		body([
			responseElement: $(producer(regex('[0-9]{7}')))
		])
		headers {
			contentType("application/vnd.fraud.v1+json")
		}
	}
}</programlisting>
<simpara>In the preceding example, the opposite side of the communication has the respective data
generated for request and response.</simpara>
<simpara>Spring Cloud Contract comes with a series of predefined regular expressions that you can
use in your contracts, as shown in the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">protected static final Pattern TRUE_OR_FALSE = Pattern.compile(/(true|false)/)
protected static final Pattern ONLY_ALPHA_UNICODE = Pattern.compile(/[\p{L}]*/)
protected static final Pattern NUMBER = Pattern.compile('-?\\d*(\\.\\d+)?')
protected static final Pattern IP_ADDRESS = Pattern.compile('([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])')
protected static final Pattern HOSTNAME_PATTERN = Pattern.compile('((http[s]?|ftp):/)/?([^:/\\s]+)(:[0-9]{1,5})?')
protected static final Pattern EMAIL = Pattern.compile('[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,6}')
protected static final Pattern URL = UrlHelper.URL
protected static final Pattern UUID = Pattern.compile('[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}')
protected static final Pattern ANY_DATE = Pattern.compile('(\\d\\d\\d\\d)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])')
protected static final Pattern ANY_DATE_TIME = Pattern.compile('([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])')
protected static final Pattern ANY_TIME = Pattern.compile('(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])')
protected static final Pattern NON_EMPTY = Pattern.compile(/[\S\s]+/)
protected static final Pattern NON_BLANK = Pattern.compile(/^\s*\S[\S\s]*/)
protected static final Pattern ISO8601_WITH_OFFSET = Pattern.compile(/([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])(\.\d{3})?(Z|[+-][01]\d:[0-5]\d)/)

protected static Pattern anyOf(String... values){
	return Pattern.compile(values.collect({"^$it\$"}).join("|"))
}

String onlyAlphaUnicode() {
	return ONLY_ALPHA_UNICODE.pattern()
}

String number() {
	return NUMBER.pattern()
}

String anyBoolean() {
	return TRUE_OR_FALSE.pattern()
}

String ipAddress() {
	return IP_ADDRESS.pattern()
}

String hostname() {
	return HOSTNAME_PATTERN.pattern()
}

String email() {
	return EMAIL.pattern()
}

String url() {
	return URL.pattern()
}

String uuid(){
	return UUID.pattern()
}

String isoDate() {
	return ANY_DATE.pattern()
}

String isoDateTime() {
	return ANY_DATE_TIME.pattern()
}

String isoTime() {
	return ANY_TIME.pattern()
}

String iso8601WithOffset() {
	return ISO8601_WITH_OFFSET.pattern()
}

String nonEmpty() {
	return NON_EMPTY.pattern()
}

String nonBlank() {
	return NON_BLANK.pattern()
}</programlisting>
<simpara>In your contract, you can use it as shown in the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract dslWithOptionalsInString = Contract.make {
	priority 1
	request {
		method POST()
		url '/users/password'
		headers {
			contentType(applicationJson())
		}
		body(
				email: $(consumer(optional(regex(email()))), producer('abc@abc.com')),
				callback_url: $(consumer(regex(hostname())), producer('http://partners.com'))
		)
	}
	response {
		status 404
		headers {
			contentType(applicationJson())
		}
		body(
				code: value(consumer("123123"), producer(optional("123123"))),
				message: "User not found by email = [${value(producer(regex(email())), consumer('not.existing@user.com'))}]"
		)
	}
}</programlisting>
</section>
<section xml:id="_passing_optional_parameters">
<title>Passing Optional Parameters</title>
<simpara>It is possible to provide optional parameters in your contract. However, you can provide
optional parameters only for the following:</simpara>
<itemizedlist>
<listitem>
<simpara><emphasis>STUB</emphasis> side of the Request</simpara>
</listitem>
<listitem>
<simpara><emphasis>TEST</emphasis> side of the Response</simpara>
</listitem>
</itemizedlist>
<simpara>The following example shows how to provide optional parameters:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	priority 1
	request {
		method 'POST'
		url '/users/password'
		headers {
			contentType(applicationJson())
		}
		body(
				email: $(consumer(optional(regex(email()))), producer('abc@abc.com')),
				callback_url: $(consumer(regex(hostname())), producer('http://partners.com'))
		)
	}
	response {
		status 404
		headers {
			header 'Content-Type': 'application/json'
		}
		body(
				code: value(consumer("123123"), producer(optional("123123")))
		)
	}
}</programlisting>
<simpara>By wrapping a part of the body with the <literal>optional()</literal> method, you create a regular
expression that must be present 0 or more times.</simpara>
<simpara>If you use Spock for, the following test would be generated from the previous example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">"""
 given:
  def request = given()
    .header("Content-Type", "application/json")
    .body('''{"email":"abc@abc.com","callback_url":"http://partners.com"}''')

 when:
  def response = given().spec(request)
    .post("/users/password")

 then:
  response.statusCode == 404
  response.header('Content-Type')  == 'application/json'
 and:
  DocumentContext parsedJson = JsonPath.parse(response.body.asString())
  assertThatJson(parsedJson).field("['code']").matches("(123123)?")
"""</programlisting>
<simpara>The following stub would also be generated:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
{
  "request" : {
    "url" : "/users/password",
    "method" : "POST",
    "bodyPatterns" : [ {
      "matchesJsonPath" : "$[?(@.['email'] =~ /([a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\\\.[a-zA-Z]{2,6})?/)]"
    }, {
      "matchesJsonPath" : "$[?(@.['callback_url'] =~ /((http[s]?|ftp):\\\\/)\\\\/?([^:\\\\/\\\\s]+)(:[0-9]{1,5})?/)]"
    } ],
    "headers" : {
      "Content-Type" : {
        "equalTo" : "application/json"
      }
    }
  },
  "response" : {
    "status" : 404,
    "body" : "{\\"code\\":\\"123123\\",\\"message\\":\\"User not found by email == [not.existing@user.com]\\"}",
    "headers" : {
      "Content-Type" : "application/json"
    }
  },
  "priority" : 1
}
'''</programlisting>
</section>
<section xml:id="_executing_custom_methods_on_the_server_side">
<title>Executing Custom Methods on the Server Side</title>
<simpara>You can define a method call that executes on the server side during the test. Such a
method can be added to the class defined as "baseClassForTests" in the configuration. The
following code shows an example of the contract portion of the test case:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		method 'PUT'
		url $(consumer(regex('^/api/[0-9]{2}$')), producer('/api/12'))
		headers {
			header 'Content-Type': 'application/json'
		}
		body '''\
				[{
					"text": "Gonna see you at Warsaw"
				}]
			'''
	}
	response {
		body (
				path: $(consumer('/api/12'), producer(regex('^/api/[0-9]{2}$'))),
				correlationId: $(consumer('1223456'), producer(execute('isProperCorrelationId($it)')))
		)
		status 200
	}
}</programlisting>
<simpara>The following code shows the base class portion of the test case:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">abstract class BaseMockMvcSpec extends Specification {

	def setup() {
		RestAssuredMockMvc.standaloneSetup(new PairIdController())
	}

	void isProperCorrelationId(Integer correlationId) {
		assert correlationId == 123456
	}

	void isEmpty(String value) {
		assert value == null
	}

}</programlisting>
<important>
<simpara>You cannot use both a String and <literal>execute</literal> to perform concatenation. For
example, calling <literal>header('Authorization', 'Bearer ' + execute('authToken()'))</literal> leads to
improper results. Instead, call <literal>header('Authorization', execute('authToken()'))</literal> and
ensure that the <literal>authToken()</literal> method returns everything you need.</simpara>
</important>
<simpara>The type of the object read from the JSON can be one of the following, depending on the
JSON path:</simpara>
<itemizedlist>
<listitem>
<simpara><literal>String</literal>: If you point to a <literal>String</literal> value in the JSON.</simpara>
</listitem>
<listitem>
<simpara><literal>JSONArray</literal>: If you point to a <literal>List</literal> in the JSON.</simpara>
</listitem>
<listitem>
<simpara><literal>Map</literal>: If you point to a <literal>Map</literal> in the JSON.</simpara>
</listitem>
<listitem>
<simpara><literal>Number</literal>: If you point to <literal>Integer</literal>, <literal>Double</literal> etc. in the JSON.</simpara>
</listitem>
<listitem>
<simpara><literal>Boolean</literal>: If you point to a <literal>Boolean</literal> in the JSON.</simpara>
</listitem>
</itemizedlist>
<simpara>In the request part of the contract, you can specify that the <literal>body</literal> should be taken from
a method.</simpara>
<important>
<simpara>You must provide both the consumer and the producer side. The <literal>execute</literal> part
is applied for the whole body - not for parts of it.</simpara>
</important>
<simpara>The following example shows how to read an object from JSON:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract contractDsl = Contract.make {
	request {
		method 'GET'
		url '/something'
		body(
				$(c("foo"), p(execute("hashCode()")))
		)
	}
	response {
		status 200
	}
}</programlisting>
<simpara>The preceding example results in calling the <literal>hashCode()</literal> method in the request body.
It should resemble the following code:</simpara>
<programlisting language="java" linenumbering="unnumbered">// given:
 MockMvcRequestSpecification request = given()
   .body(hashCode());

// when:
 ResponseOptions response = given().spec(request)
   .get("/something");

// then:
 assertThat(response.statusCode()).isEqualTo(200);</programlisting>
</section>
<section xml:id="_referencing_the_request_from_the_response">
<title>Referencing the Request from the Response</title>
<simpara>The best situation is to provide fixed values, but sometimes you need to reference a
request in your response. To do so, you can use the <literal>fromRequest()</literal> method, which lets
you reference a bunch of elements from the HTTP request. You can use the following
options:</simpara>
<itemizedlist>
<listitem>
<simpara><literal>fromRequest().url()</literal>: Returns the request URL and query parameters.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().query(String key)</literal>: Returns the first query parameter with a given name.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().query(String key, int index)</literal>: Returns the nth query parameter with a
given name.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().path()</literal>: Returns the full path.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().path(int index)</literal>: Returns the nth path element.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().header(String key)</literal>: Returns the first header with a given name.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().header(String key, int index)</literal>: Returns the nth header with a given name.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().body()</literal>: Returns the full request body.</simpara>
</listitem>
<listitem>
<simpara><literal>fromRequest().body(String jsonPath)</literal>: Returns the element from the request that
matches the JSON Path.</simpara>
</listitem>
</itemizedlist>
<simpara>Consider the following contract:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract contractDsl = Contract.make {
	request {
		method 'GET'
		url('/api/v1/xxxx') {
			queryParameters {
				parameter("foo", "bar")
				parameter("foo", "bar2")
			}
		}
		headers {
			header(authorization(), "secret")
			header(authorization(), "secret2")
		}
		body(foo: "bar", baz: 5)
	}
	response {
		status 200
		headers {
			header(authorization(), "foo ${fromRequest().header(authorization())} bar")
		}
		body(
				url: fromRequest().url(),
				param: fromRequest().query("foo"),
				paramIndex: fromRequest().query("foo", 1),
				authorization: fromRequest().header("Authorization"),
				authorization2: fromRequest().header("Authorization", 1),
				fullBody: fromRequest().body(),
				responseFoo: fromRequest().body('$.foo'),
				responseBaz: fromRequest().body('$.baz'),
				responseBaz2: "Bla bla ${fromRequest().body('$.foo')} bla bla"
		)
	}
}</programlisting>
<simpara>Running a JUnit test generation leads to a test that resembles the following example:</simpara>
<programlisting language="java" linenumbering="unnumbered">// given:
 MockMvcRequestSpecification request = given()
   .header("Authorization", "secret")
   .header("Authorization", "secret2")
   .body("{\"foo\":\"bar\",\"baz\":5}");

// when:
 ResponseOptions response = given().spec(request)
   .queryParam("foo","bar")
   .queryParam("foo","bar2")
   .get("/api/v1/xxxx");

// then:
 assertThat(response.statusCode()).isEqualTo(200);
 assertThat(response.header("Authorization")).isEqualTo("foo secret bar");
// and:
 DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
 assertThatJson(parsedJson).field("['fullBody']").isEqualTo("{\"foo\":\"bar\",\"baz\":5}");
 assertThatJson(parsedJson).field("['authorization']").isEqualTo("secret");
 assertThatJson(parsedJson).field("['authorization2']").isEqualTo("secret2");
 assertThatJson(parsedJson).field("['path']").isEqualTo("/api/v1/xxxx");
 assertThatJson(parsedJson).field("['param']").isEqualTo("bar");
 assertThatJson(parsedJson).field("['paramIndex']").isEqualTo("bar2");
 assertThatJson(parsedJson).field("['pathIndex']").isEqualTo("v1");
 assertThatJson(parsedJson).field("['responseBaz']").isEqualTo(5);
 assertThatJson(parsedJson).field("['responseFoo']").isEqualTo("bar");
 assertThatJson(parsedJson).field("['url']").isEqualTo("/api/v1/xxxx?foo=bar&amp;foo=bar2");
 assertThatJson(parsedJson).field("['responseBaz2']").isEqualTo("Bla bla bar bla bla");</programlisting>
<simpara>As you can see, elements from the request have been properly referenced in the response.</simpara>
<simpara>The generated WireMock stub should resemble the following example:</simpara>
<programlisting language="json" linenumbering="unnumbered">{
  "request" : {
    "urlPath" : "/api/v1/xxxx",
    "method" : "POST",
    "headers" : {
      "Authorization" : {
        "equalTo" : "secret2"
      }
    },
    "queryParameters" : {
      "foo" : {
        "equalTo" : "bar2"
      }
    },
    "bodyPatterns" : [ {
      "matchesJsonPath" : "$[?(@.['baz'] == 5)]"
    }, {
      "matchesJsonPath" : "$[?(@.['foo'] == 'bar')]"
    } ]
  },
  "response" : {
    "status" : 200,
    "body" : "{\"authorization\":\"{{{request.headers.Authorization.[0]}}}\",\"path\":\"{{{request.path}}}\",\"responseBaz\":{{{jsonpath this '$.baz'}}} ,\"param\":\"{{{request.query.foo.[0]}}}\",\"pathIndex\":\"{{{request.path.[1]}}}\",\"responseBaz2\":\"Bla bla {{{jsonpath this '$.foo'}}} bla bla\",\"responseFoo\":\"{{{jsonpath this '$.foo'}}}\",\"authorization2\":\"{{{request.headers.Authorization.[1]}}}\",\"fullBody\":\"{{{escapejsonbody}}}\",\"url\":\"{{{request.url}}}\",\"paramIndex\":\"{{{request.query.foo.[1]}}}\"}",
    "headers" : {
      "Authorization" : "{{{request.headers.Authorization.[0]}}};foo"
    },
    "transformers" : [ "response-template" ]
  }
}</programlisting>
<simpara>Sending a request such as the one presented in the <literal>request</literal> part of the contract results
in sending the following response body:</simpara>
<programlisting language="json" linenumbering="unnumbered">{
  "url" : "/api/v1/xxxx?foo=bar&amp;foo=bar2",
  "path" : "/api/v1/xxxx",
  "pathIndex" : "v1",
  "param" : "bar",
  "paramIndex" : "bar2",
  "authorization" : "secret",
  "authorization2" : "secret2",
  "fullBody" : "{\"foo\":\"bar\",\"baz\":5}",
  "responseFoo" : "bar",
  "responseBaz" : 5,
  "responseBaz2" : "Bla bla bar bla bla"
}</programlisting>
<important>
<simpara>This feature works only with WireMock having a version greater than or equal
to 2.5.1. The Spring Cloud Contract Verifier uses WireMock&#8217;s
<literal>response-template</literal> response transformer. It uses Handlebars to convert the Mustache <literal>{{{ }}}</literal> templates into
proper values. Additionally, it registers two helper functions:</simpara>
</important>
<itemizedlist>
<listitem>
<simpara><literal>escapejsonbody</literal>: Escapes the request body in a format that can be embedded in a JSON.</simpara>
</listitem>
<listitem>
<simpara><literal>jsonpath</literal>: For a given parameter, find an object in the request body.</simpara>
</listitem>
</itemizedlist>
</section>
<section xml:id="_registering_your_own_wiremock_extension">
<title>Registering Your Own WireMock Extension</title>
<simpara>WireMock lets you register custom extensions. By default, Spring Cloud Contract registers
the transformer, which lets you reference a request from a response. If you want to
provide your own extensions, you can register an implementation of the
<literal>org.springframework.cloud.contract.verifier.dsl.wiremock.WireMockExtensions</literal> interface.
Since we use the spring.factories extension approach, you can create an entry in
<literal>META-INF/spring.factories</literal> file similar to the following:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Unresolved directive in verifier_contract.adoc - include::../../../../spring-cloud-contract-stub-runner/src/test/resources/META-INF/spring.factories[indent=0]</programlisting>
<simpara>The following is an example of a custom extension:</simpara>
<formalpara>
<title>TestWireMockExtensions.groovy</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">Unresolved directive in verifier_contract.adoc - include::../../../../spring-cloud-contract-stub-runner/src/test/groovy/org/springframework/cloud/contract/verifier/dsl/wiremock/TestWireMockExtensions.groovy[indent=0]</programlisting>
</para>
</formalpara>
<important>
<simpara>Remember to override the <literal>applyGlobally()</literal> method and set it to <literal>false</literal> if you
want the transformation to be applied only for a mapping that explicitly requires it.</simpara>
</important>
</section>
<section xml:id="_dynamic_properties_in_the_matchers_sections">
<title>Dynamic Properties in the Matchers Sections</title>
<simpara>If you work with <link xl:href="https://docs.pact.io/">Pact</link>, the following discussion may seem familiar.
Quite a few users are used to having a separation between the body and setting the
dynamic parts of a contract.</simpara>
<simpara>You can use two separate sections:</simpara>
<itemizedlist>
<listitem>
<simpara><literal>stubMatchers</literal>, which lets you define the dynamic values that should end up in a stub.
You can set it in the <literal>request</literal> or <literal>inputMessage</literal> part of your contract.</simpara>
</listitem>
<listitem>
<simpara><literal>testMatchers</literal>, which is present in the <literal>response</literal> or <literal>outputMessage</literal> side of the
contract.</simpara>
</listitem>
</itemizedlist>
<simpara>Currently, Spring Cloud Contract Verifier supports only JSON Path-based matchers with the
following matching possibilities:</simpara>
<itemizedlist>
<listitem>
<simpara>For <literal>stubMatchers</literal>:</simpara>
<itemizedlist>
<listitem>
<simpara><literal>byEquality()</literal>: The value taken from the response via the provided JSON Path must be
equal to the value provided in the contract.</simpara>
</listitem>
<listitem>
<simpara><literal>byRegex(&#8230;&#8203;)</literal>: The value taken from the response via the provided JSON Path must
match the regex.</simpara>
</listitem>
<listitem>
<simpara><literal>byDate()</literal>: The value taken from the response via the provided JSON Path must
match the regex for an ISO Date value.</simpara>
</listitem>
<listitem>
<simpara><literal>byTimestamp()</literal>: The value taken from the response via the provided JSON Path must
match the regex for an ISO DateTime value.</simpara>
</listitem>
<listitem>
<simpara><literal>byTime()</literal>: The value taken from the response via the provided JSON Path must
match the regex for an ISO Time value.</simpara>
</listitem>
</itemizedlist>
</listitem>
<listitem>
<simpara>For <literal>testMatchers</literal>:</simpara>
<itemizedlist>
<listitem>
<simpara><literal>byEquality()</literal>: The value taken from the response via the provided JSON Path must be
equal to the provided value in the contract.</simpara>
</listitem>
<listitem>
<simpara><literal>byRegex(&#8230;&#8203;)</literal>: The value taken from the response via the provided JSON Path must
match the regex.</simpara>
</listitem>
<listitem>
<simpara><literal>byDate()</literal>: The value taken from the response via the provided JSON Path must match
the regex for an ISO Date value.</simpara>
</listitem>
<listitem>
<simpara><literal>byTimestamp()</literal>: The value taken from the response via the provided JSON Path must
match the regex for an ISO DateTime value.</simpara>
</listitem>
<listitem>
<simpara><literal>byTime()</literal>: The value taken from the response via the provided JSON Path must match
the regex for an ISO Time value.</simpara>
</listitem>
<listitem>
<simpara><literal>byType()</literal>: The value taken from the response via the provided JSON Path needs to be
of the same type as the type defined in the body of the response in the contract.
<literal>byType</literal> can take a closure, in which you can set <literal>minOccurrence</literal> and <literal>maxOccurrence</literal>.
That way, you can assert the size of the flattened collection. To check the size of an
unflattened collection, use a custom method with the <literal>byCommand(&#8230;&#8203;)</literal> testMatcher.</simpara>
</listitem>
<listitem>
<simpara><literal>byCommand(&#8230;&#8203;)</literal>: The value taken from the response via the provided JSON Path is
passed as an input to the custom method that you provide. For example,
<literal>byCommand('foo($it)')</literal> results in calling a <literal>foo</literal> method to which the value matching the
JSON Path gets passed. The type of the object read from the JSON can be one of the
following, depending on the JSON path:</simpara>
<itemizedlist>
<listitem>
<simpara><literal>String</literal>: If you point to a <literal>String</literal> value.</simpara>
</listitem>
<listitem>
<simpara><literal>JSONArray</literal>: If you point to a <literal>List</literal>.</simpara>
</listitem>
<listitem>
<simpara><literal>Map</literal>: If you point to a <literal>Map</literal>.</simpara>
</listitem>
<listitem>
<simpara><literal>Number</literal>: If you point to <literal>Integer</literal>, <literal>Double</literal>, or other kind of number.</simpara>
</listitem>
<listitem>
<simpara><literal>Boolean</literal>: If you point to a <literal>Boolean</literal>.</simpara>
</listitem>
</itemizedlist>
</listitem>
</itemizedlist>
</listitem>
</itemizedlist>
<simpara>Consider the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract contractDsl = Contract.make {
	request {
		method 'GET'
		urlPath '/get'
		body([
				duck: 123,
				alpha: "abc",
				number: 123,
				aBoolean: true,
				date: "2017-01-01",
				dateTime: "2017-01-01T01:23:45",
				time: "01:02:34",
				valueWithoutAMatcher: "foo",
				valueWithTypeMatch: "string",
				key: [
						'complex.key' : 'foo'
				]
		])
		stubMatchers {
			jsonPath('$.duck', byRegex("[0-9]{3}"))
			jsonPath('$.duck', byEquality())
			jsonPath('$.alpha', byRegex(onlyAlphaUnicode()))
			jsonPath('$.alpha', byEquality())
			jsonPath('$.number', byRegex(number()))
			jsonPath('$.aBoolean', byRegex(anyBoolean()))
			jsonPath('$.date', byDate())
			jsonPath('$.dateTime', byTimestamp())
			jsonPath('$.time', byTime())
			jsonPath("\$.['key'].['complex.key']", byEquality())
		}
		headers {
			contentType(applicationJson())
		}
	}
	response {
		status 200
		body([
				duck: 123,
				alpha: "abc",
				number: 123,
				aBoolean: true,
				date: "2017-01-01",
				dateTime: "2017-01-01T01:23:45",
				time: "01:02:34",
				valueWithoutAMatcher: "foo",
				valueWithTypeMatch: "string",
				valueWithMin: [
					1,2,3
				],
				valueWithMax: [
					1,2,3
				],
				valueWithMinMax: [
					1,2,3
				],
				valueWithMinEmpty: [],
				valueWithMaxEmpty: [],
				key: [
				        'complex.key' : 'foo'
				]
		])
		testMatchers {
			// asserts the jsonpath value against manual regex
			jsonPath('$.duck', byRegex("[0-9]{3}"))
			// asserts the jsonpath value against the provided value
			jsonPath('$.duck', byEquality())
			// asserts the jsonpath value against some default regex
			jsonPath('$.alpha', byRegex(onlyAlphaUnicode()))
			jsonPath('$.alpha', byEquality())
			jsonPath('$.number', byRegex(number()))
			jsonPath('$.aBoolean', byRegex(anyBoolean()))
			// asserts vs inbuilt time related regex
			jsonPath('$.date', byDate())
			jsonPath('$.dateTime', byTimestamp())
			jsonPath('$.time', byTime())
			// asserts that the resulting type is the same as in response body
			jsonPath('$.valueWithTypeMatch', byType())
			jsonPath('$.valueWithMin', byType {
				// results in verification of size of array (min 1)
				minOccurrence(1)
			})
			jsonPath('$.valueWithMax', byType {
				// results in verification of size of array (max 3)
				maxOccurrence(3)
			})
			jsonPath('$.valueWithMinMax', byType {
				// results in verification of size of array (min 1 &amp; max 3)
				minOccurrence(1)
				maxOccurrence(3)
			})
			jsonPath('$.valueWithMinEmpty', byType {
				// results in verification of size of array (min 0)
				minOccurrence(0)
			})
			jsonPath('$.valueWithMaxEmpty', byType {
				// results in verification of size of array (max 0)
				maxOccurrence(0)
			})
			// will execute a method `assertThatValueIsANumber`
			jsonPath('$.duck', byCommand('assertThatValueIsANumber($it)'))
			jsonPath("\$.['key'].['complex.key']", byEquality())
		}
		headers {
			contentType(applicationJson())
		}
	}
}</programlisting>
<simpara>In the preceding example, you can see the dynamic portions of the contract in the
<literal>matchers</literal> sections. For the request part, you can see that, for all fields but
<literal>valueWithoutAMatcher</literal>, the values of the regular expressions that the stub should
contain are explicitly set. For the <literal>valueWithoutAMatcher</literal>, the verification takes place
in the same way as without the use of matchers. In that case, the test performs an
equality check.</simpara>
<simpara>For the response side in the <literal>testMatchers</literal> section, we define the dynamic parts in a
similar manner. The only difference is that the <literal>byType</literal> matchers are also present. The
verifier engine checks four fields to verify whether the response from the test
has a value for which the JSON path matches the given field, is of the same type as the one
defined in the response body, and passes the following check (based on the method being called):</simpara>
<itemizedlist>
<listitem>
<simpara>For <literal>$.valueWithTypeMatch</literal>, the engine checks whether the type is the same.</simpara>
</listitem>
<listitem>
<simpara>For <literal>$.valueWithMin</literal>, the engine check the type and asserts whether the size is greater
than or equal to the minimum occurrence.</simpara>
</listitem>
<listitem>
<simpara>For <literal>$.valueWithMax</literal>, the engine checks the type and asserts whether the size is
smaller than or equal to the maximum occurrence.</simpara>
</listitem>
<listitem>
<simpara>For <literal>$.valueWithMinMax</literal>, the engine checks the type and asserts whether the size is
between the min and maximum occurrence.</simpara>
</listitem>
</itemizedlist>
<simpara>The resulting test would resemble the following example (note that an <literal>and</literal> section
separates the autogenerated assertions and the assertion from matchers):</simpara>
<programlisting language="java" linenumbering="unnumbered">// given:
 MockMvcRequestSpecification request = given()
   .header("Content-Type", "application/json")
   .body("{\"duck\":123,\"alpha\":\"abc\",\"number\":123,\"aBoolean\":true,\"date\":\"2017-01-01\",\"dateTime\":\"2017-01-01T01:23:45\",\"time\":\"01:02:34\",\"valueWithoutAMatcher\":\"foo\",\"valueWithTypeMatch\":\"string\"}");

// when:
 ResponseOptions response = given().spec(request)
   .get("/get");

// then:
 assertThat(response.statusCode()).isEqualTo(200);
 assertThat(response.header("Content-Type")).matches("application/json.*");
// and:
 DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
 assertThatJson(parsedJson).field("valueWithoutAMatcher").isEqualTo("foo");
// and:
 assertThat(parsedJson.read("$.duck", String.class)).matches("[0-9]{3}");
 assertThat(parsedJson.read("$.duck", Integer.class)).isEqualTo(123);
 assertThat(parsedJson.read("$.alpha", String.class)).matches("[\\p{L}]*");
 assertThat(parsedJson.read("$.alpha", String.class)).isEqualTo("abc");
 assertThat(parsedJson.read("$.number", String.class)).matches("-?\\d*(\\.\\d+)?");
 assertThat(parsedJson.read("$.aBoolean", String.class)).matches("(true|false)");
 assertThat(parsedJson.read("$.date", String.class)).matches("(\\d\\d\\d\\d)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])");
 assertThat(parsedJson.read("$.dateTime", String.class)).matches("([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])");
 assertThat(parsedJson.read("$.time", String.class)).matches("(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])");
 assertThat((Object) parsedJson.read("$.valueWithTypeMatch")).isInstanceOf(java.lang.String.class);
 assertThat((Object) parsedJson.read("$.valueWithMin")).isInstanceOf(java.util.List.class);
 assertThat((java.lang.Iterable) parsedJson.read("$.valueWithMin", java.util.Collection.class)).hasSizeGreaterThanOrEqualTo(1);
 assertThat((Object) parsedJson.read("$.valueWithMax")).isInstanceOf(java.util.List.class);
 assertThat((java.lang.Iterable) parsedJson.read("$.valueWithMax", java.util.Collection.class)).hasSizeLessThanOrEqualTo(3);
 assertThat((Object) parsedJson.read("$.valueWithMinMax")).isInstanceOf(java.util.List.class);
 assertThat((java.lang.Iterable) parsedJson.read("$.valueWithMinMax", java.util.Collection.class)).hasSizeBetween(1, 3);
 assertThat((Object) parsedJson.read("$.valueWithMinEmpty")).isInstanceOf(java.util.List.class);
 assertThat((java.lang.Iterable) parsedJson.read("$.valueWithMinEmpty", java.util.Collection.class)).hasSizeGreaterThanOrEqualTo(0);
 assertThat((Object) parsedJson.read("$.valueWithMaxEmpty")).isInstanceOf(java.util.List.class);
 assertThat((java.lang.Iterable) parsedJson.read("$.valueWithMaxEmpty", java.util.Collection.class)).hasSizeLessThanOrEqualTo(0);
 assertThatValueIsANumber(parsedJson.read("$.duck"));</programlisting>
<important>
<simpara>Notice that, for the <literal>byCommand</literal> method, the example calls the
<literal>assertThatValueIsANumber</literal>. This method must be defined in the test base class or be
statically imported to your tests. Notice that the <literal>byCommand</literal> call was converted to
<literal>assertThatValueIsANumber(parsedJson.read("$.duck"));</literal>. That means that the engine took
the method name and passed the proper JSON path as a parameter to it.</simpara>
</important>
<simpara>The resulting WireMock stub is in the following example:</simpara>
<programlisting language="json" linenumbering="unnumbered">				'''
{
  "request" : {
    "urlPath" : "/get",
    "method" : "POST",
    "headers" : {
      "Content-Type" : {
        "matches" : "application/json.*"
      }
    },
    "bodyPatterns" : [ {
      "matchesJsonPath" : "$[?(@.['valueWithoutAMatcher'] == 'foo')]"
    }, {
      "matchesJsonPath" : "$[?(@.['valueWithTypeMatch'] == 'string')]"
    }, {
      "matchesJsonPath" : "$.['list'].['some'].['nested'][?(@.['anothervalue'] == 4)]"
    }, {
      "matchesJsonPath" : "$.['list'].['someother'].['nested'][?(@.['anothervalue'] == 4)]"
    }, {
      "matchesJsonPath" : "$.['list'].['someother'].['nested'][?(@.['json'] == 'with value')]"
    }, {
      "matchesJsonPath" : "$[?(@.duck =~ /([0-9]{3})/)]"
    }, {
      "matchesJsonPath" : "$[?(@.duck == 123)]"
    }, {
      "matchesJsonPath" : "$[?(@.alpha =~ /([\\\\p{L}]*)/)]"
    }, {
      "matchesJsonPath" : "$[?(@.alpha == 'abc')]"
    }, {
      "matchesJsonPath" : "$[?(@.number =~ /(-?\\\\d*(\\\\.\\\\d+)?)/)]"
    }, {
      "matchesJsonPath" : "$[?(@.aBoolean =~ /((true|false))/)]"
    }, {
      "matchesJsonPath" : "$[?(@.date =~ /((\\\\d\\\\d\\\\d\\\\d)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01]))/)]"
    }, {
      "matchesJsonPath" : "$[?(@.dateTime =~ /(([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9]))/)]"
    }, {
      "matchesJsonPath" : "$[?(@.time =~ /((2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9]))/)]"
    }, {
      "matchesJsonPath" : "$.list.some.nested[?(@.json =~ /(.*)/)]"
    } ]
  },
  "response" : {
    "status" : 200,
    "body" : "{\\"duck\\":123,\\"alpha\\":\\"abc\\",\\"number\\":123,\\"aBoolean\\":true,\\"date\\":\\"2017-01-01\\",\\"dateTime\\":\\"2017-01-01T01:23:45\\",\\"time\\":\\"01:02:34\\",\\"valueWithoutAMatcher\\":\\"foo\\",\\"valueWithTypeMatch\\":\\"string\\",\\"valueWithMin\\":[1,2,3],\\"valueWithMax\\":[1,2,3],\\"valueWithMinMax\\":[1,2,3]}",
    "headers" : {
      "Content-Type" : "application/json"
    }
  }
}
'''</programlisting>
<important>
<simpara>If you use a <literal>matcher</literal>, then the part of the request aned response that the
<literal>matcher</literal> addresses with the JSON Path gets removed from the assertion. In the case of
verifying a collection, you must create matchers for <emphasis role="strong">all</emphasis> the elements of the
collection.</simpara>
</important>
<simpara>Consider the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
    request {
        method 'GET'
        url("/foo")
    }
    response {
        status 200
        body(events: [[
                                 operation          : 'EXPORT',
                                 eventId            : '16f1ed75-0bcc-4f0d-a04d-3121798faf99',
                                 status             : 'OK'
                         ], [
                                 operation          : 'INPUT_PROCESSING',
                                 eventId            : '3bb4ac82-6652-462f-b6d1-75e424a0024a',
                                 status             : 'OK'
                         ]
                ]
        )
        testMatchers {
            jsonPath('$.events[0].operation', byRegex('.+'))
            jsonPath('$.events[0].eventId', byRegex('^([a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12})$'))
            jsonPath('$.events[0].status', byRegex('.+'))
        }
    }
}</programlisting>
<simpara>The preceding code leads to creating the following test (the code block shows only the assertion section):</simpara>
<programlisting language="java" linenumbering="unnumbered">and:
	DocumentContext parsedJson = JsonPath.parse(response.body.asString())
	assertThatJson(parsedJson).array("['events']").contains("['eventId']").isEqualTo("16f1ed75-0bcc-4f0d-a04d-3121798faf99")
	assertThatJson(parsedJson).array("['events']").contains("['operation']").isEqualTo("EXPORT")
	assertThatJson(parsedJson).array("['events']").contains("['operation']").isEqualTo("INPUT_PROCESSING")
	assertThatJson(parsedJson).array("['events']").contains("['eventId']").isEqualTo("3bb4ac82-6652-462f-b6d1-75e424a0024a")
	assertThatJson(parsedJson).array("['events']").contains("['status']").isEqualTo("OK")
and:
	assertThat(parsedJson.read("\$.events[0].operation", String.class)).matches(".+")
	assertThat(parsedJson.read("\$.events[0].eventId", String.class)).matches("^([a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12})\$")
	assertThat(parsedJson.read("\$.events[0].status", String.class)).matches(".+")</programlisting>
<simpara>As you can see, the assertion is malformed. Only the first element of the array got
asserted. In order to fix this, you should apply the assertion to the whole <literal>$.events</literal>
collection and assert it with the <literal>byCommand(&#8230;&#8203;)</literal> method.</simpara>
</section>
</section>
<section xml:id="_jax_rs_support">
<title>JAX-RS Support</title>
<simpara>The Spring Cloud Contract Verifier supports the JAX-RS 2 Client API. The base class needs
to define <literal>protected WebTarget webTarget</literal> and server initialization. The only option for
testing JAX-RS API is to start a web server. Also, a request with a body needs to have a
content type set. Otherwise, the default of <literal>application/octet-stream</literal> gets used.</simpara>
<simpara>In order to use JAX-RS mode, use the following settings:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">testMode == 'JAXRSCLIENT'</programlisting>
<simpara>The following example shows a generated test API:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">'''
 // when:
  Response response = webTarget
    .path("/users")
    .queryParam("limit", "10")
    .queryParam("offset", "20")
    .queryParam("filter", "email")
    .queryParam("sort", "name")
    .queryParam("search", "55")
    .queryParam("age", "99")
    .queryParam("name", "Denis.Stepanov")
    .queryParam("email", "bob@email.com")
    .request()
    .method("GET");

  String responseAsString = response.readEntity(String.class);

 // then:
  assertThat(response.getStatus()).isEqualTo(200);
 // and:
  DocumentContext parsedJson = JsonPath.parse(responseAsString);
  assertThatJson(parsedJson).field("['property1']").isEqualTo("a");
'''</programlisting>
</section>
<section xml:id="_async_support">
<title>Async Support</title>
<simpara>If you&#8217;re using asynchronous communication on the server side (your controllers are
returning <literal>Callable</literal>, <literal>DeferredResult</literal>, and so on), then, inside your contract, you must
provide a <literal>sync()</literal> method in the <literal>response</literal> section. The following code shows an example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
    request {
        method GET()
        url '/get'
    }
    response {
        status 200
        body 'Passed'
        async()
    }
}</programlisting>
</section>
<section xml:id="_working_with_context_paths">
<title>Working with Context Paths</title>
<simpara>Spring Cloud Contract supports context paths.</simpara>
<important>
<simpara>The only change needed to fully support context paths is the switch on the
<emphasis role="strong">PRODUCER</emphasis> side. Also, the autogenerated tests must use <emphasis role="strong">EXPLICIT</emphasis> mode. The  consumer
side remains untouched. In order for the generated test to pass, you must use <emphasis role="strong">EXPLICIT</emphasis>
mode.</simpara>
</important>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
    &lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
    &lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
    &lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
    &lt;extensions&gt;true&lt;/extensions&gt;
    &lt;configuration&gt;
        &lt;testMode&gt;EXPLICIT&lt;/testMode&gt;
    &lt;/configuration&gt;
&lt;/plugin&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">contracts {
		testMode = 'EXPLICIT'
}</programlisting>
</para>
</formalpara>
<simpara>That way, you generate a test that <emphasis role="strong">DOES NOT</emphasis> use MockMvc. It means that you generate
real requests and you need to setup your generated test&#8217;s base class to work on a real
socket.</simpara>
<simpara>Consider the following contract:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">org.springframework.cloud.contract.spec.Contract.make {
	request {
		method 'GET'
		url '/my-context-path/url'
	}
	response {
		status 200
	}
}</programlisting>
<simpara>The following example shows how to set up a base class and Rest Assured:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">import com.jayway.restassured.RestAssured;
import org.junit.Before;
import org.springframework.boot.context.embedded.LocalServerPort;
import org.springframework.boot.test.context.SpringBootTest;

@SpringBootTest(classes = ContextPathTestingBaseClass.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
class ContextPathTestingBaseClass {

	@LocalServerPort int port;

	@Before
	public void setup() {
		RestAssured.baseURI = "http://localhost";
		RestAssured.port = this.port;
	}
}</programlisting>
<simpara>If you do it this way:</simpara>
<itemizedlist>
<listitem>
<simpara>All of your requests in the autogenerated tests are sent to the real endpoint with your
context path included (for example, <literal>/my-context-path/url</literal>).</simpara>
</listitem>
<listitem>
<simpara>Your contracts reflect that you have a context path. Your generated stubs also have
that information (for example, in the stubs, you have to call <literal>/my-context-path/url</literal>).</simpara>
</listitem>
</itemizedlist>
</section>
<section xml:id="_messaging_top_level_elements">
<title>Messaging Top-Level Elements</title>
<simpara>The DSL for messaging looks a little bit different than the one that focuses on HTTP. The
following sections explain the differences:</simpara>
<itemizedlist>
<listitem>
<simpara><xref linkend="contract-dsl-output-triggered-method"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-output-triggered-message"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-consumer-producer"/></simpara>
</listitem>
<listitem>
<simpara><xref linkend="contract-dsl-common"/></simpara>
</listitem>
</itemizedlist>
<section xml:id="contract-dsl-output-triggered-method">
<title>Output Triggered by a Method</title>
<simpara>The output message can be triggered by calling a method (such as a <literal>Scheduler</literal> when a was
started and a message was sent), as shown in the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">def dsl = Contract.make {
	// Human readable description
	description 'Some description'
	// Label by means of which the output message can be triggered
	label 'some_label'
	// input to the contract
	input {
		// the contract will be triggered by a method
		triggeredBy('bookReturnedTriggered()')
	}
	// output message of the contract
	outputMessage {
		// destination to which the output message will be sent
		sentTo('output')
		// the body of the output message
		body('''{ "bookName" : "foo" }''')
		// the headers of the output message
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
<simpara>In the previous example case, the output message is sent to <literal>output</literal> if a method called
<literal>bookReturnedTriggered</literal> is executed. On the message <emphasis role="strong">publisher&#8217;s</emphasis> side, we generate a
test that calls that method to trigger the message. On the <emphasis role="strong">consumer</emphasis> side, you can use
the <literal>some_label</literal> to trigger the message.</simpara>
</section>
<section xml:id="contract-dsl-output-triggered-message">
<title>Output Triggered by a Message</title>
<simpara>The output message can be triggered by receiving a message, as shown in the following
example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">def dsl = Contract.make {
	description 'Some Description'
	label 'some_label'
	// input is a message
	input {
		// the message was received from this destination
		messageFrom('input')
		// has the following body
		messageBody([
		        bookName: 'foo'
		])
		// and the following headers
		messageHeaders {
			header('sample', 'header')
		}
	}
	outputMessage {
		sentTo('output')
		body([
		        bookName: 'foo'
		])
		headers {
			header('BOOK-NAME', 'foo')
		}
	}
}</programlisting>
<simpara>In the preceding example, the output message is sent to <literal>output</literal> if a proper message is
received on the <literal>input</literal> destination. On the message <emphasis role="strong">publisher&#8217;s</emphasis> side, the engine
generates a test that sends the input message to the defined destination. On the
<emphasis role="strong">consumer</emphasis> side, you can either send a message to the input destination or use a label
(<literal>some_label</literal> in the example) to trigger the message.</simpara>
</section>
<section xml:id="contract-dsl-consumer-producer">
<title>Consumer/Producer</title>
<simpara>In HTTP, you have a notion of <literal>client</literal>/<literal>stub and `server</literal>/<literal>test</literal> notation. You can also
use those paradigms in messaging. In addition, Spring Cloud Contract Verifier also
provides the <literal>consumer</literal> and <literal>producer</literal> methods, as presented in the following example
(note that you can use either <literal>$</literal> or <literal>value</literal> methods to provide <literal>consumer</literal> and <literal>producer</literal>
parts):</simpara>
<programlisting language="groovy" linenumbering="unnumbered">Contract.make {
	label 'some_label'
	input {
		messageFrom value(consumer('jms:output'), producer('jms:input'))
		messageBody([
				bookName: 'foo'
		])
		messageHeaders {
			header('sample', 'header')
		}
	}
	outputMessage {
		sentTo $(consumer('jms:input'), producer('jms:output'))
		body([
				bookName: 'foo'
		])
	}
}</programlisting>
</section>
<section xml:id="contract-dsl-common">
<title>Common</title>
<simpara>In the <literal>input {}</literal> or <literal>outputMessage {}</literal> section you can call <literal>assertThat</literal> with the name
of a <literal>method</literal> (e.g. <literal>assertThatMessageIsOnTheQueue()</literal>) that you have defined in the
base class or in a static import. Spring Cloud Pipelines will execute that method
in the genertaed test.</simpara>
</section>
</section>
<section xml:id="_multiple_contracts_in_one_file">
<title>Multiple Contracts in One File</title>
<simpara>You can define multiple contracts in one file. Such a contract might resemble the
following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">import org.springframework.cloud.contract.spec.Contract

[
        Contract.make {
            name("should post a user")
            request {
                method 'POST'
                url('/users/1')
            }
            response {
                status 200
            }
        },
        Contract.make {
            request {
                method 'POST'
                url('/users/2')
            }
            response {
                status 200
            }
        }
]</programlisting>
<simpara>In the preceding example, one contract has the <literal>name</literal> field and the other does not. This
leads to generation of two tests that look more or less like this:</simpara>
<programlisting language="java" linenumbering="unnumbered">package org.springframework.cloud.contract.verifier.tests.com.hello;

import com.example.TestBase;
import com.jayway.jsonpath.DocumentContext;
import com.jayway.jsonpath.JsonPath;
import com.jayway.restassured.module.mockmvc.specification.MockMvcRequestSpecification;
import com.jayway.restassured.response.ResponseOptions;
import org.junit.Test;

import static com.jayway.restassured.module.mockmvc.RestAssuredMockMvc.*;
import static com.toomuchcoding.jsonassert.JsonAssertion.assertThatJson;
import static org.assertj.core.api.Assertions.assertThat;

public class V1Test extends TestBase {

	@Test
	public void validate_should_post_a_user() throws Exception {
		// given:
			MockMvcRequestSpecification request = given();

		// when:
			ResponseOptions response = given().spec(request)
					.post("/users/1");

		// then:
			assertThat(response.statusCode()).isEqualTo(200);
	}

	@Test
	public void validate_withList_1() throws Exception {
		// given:
			MockMvcRequestSpecification request = given();

		// when:
			ResponseOptions response = given().spec(request)
					.post("/users/2");

		// then:
			assertThat(response.statusCode()).isEqualTo(200);
	}

}</programlisting>
<simpara>Notice that, for the contract that has the <literal>name</literal> field, the generated test method is named
<literal>validate_should_post_a_user</literal>. For the one that does not have the name, it is called
<literal>validate_withList_1</literal>. It corresponds to the name of the file <literal>WithList.groovy</literal> and the
index of the contract in the list.</simpara>
<simpara>The generated stubs is shown in the following example:</simpara>
<screen>should post a user.json
1_WithList.json</screen>
<simpara>As you can see, the first file got the <literal>name</literal> parameter from the contract. The second
got the name of the contract file (<literal>WithList.groovy</literal>) prefixed with the index (in this
case, the contract had an index of <literal>1</literal> in the list of contracts in the file).</simpara>
<tip>
<simpara>As you can see, it iss much better if you name your contracts because doing so makes
your tests far more meaningful.</simpara>
</tip>
</section>
</chapter>
<chapter xml:id="_customization">
<title>Customization</title>
<simpara>You can customize the Spring Cloud Contract Verifier by extending the DSL, as shown in
the remainder of this section.</simpara>
<section xml:id="_extending_the_dsl">
<title>Extending the DSL</title>
<simpara>You can provide your own functions to the DSL. The key requirement for this feature is to
maintain the static compatibility. Later in this document, you can see examples of:</simpara>
<itemizedlist>
<listitem>
<simpara>Creating a JAR with reusable classes.</simpara>
</listitem>
<listitem>
<simpara>Referencing of these classes in the DSLs.</simpara>
</listitem>
</itemizedlist>
<simpara>You can find the full example
<link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples">here</link>.</simpara>
<section xml:id="_common_jar">
<title>Common JAR</title>
<simpara>The following examples show three classes that can be reused in the DSLs.</simpara>
<simpara><emphasis role="strong">PatternUtils</emphasis> contains functions used by both the <emphasis role="strong">consumer</emphasis> and the <emphasis role="strong">producer</emphasis>.</simpara>
<programlisting language="java" linenumbering="unnumbered">package com.example;

import java.util.regex.Pattern;

/**
 * If you want to use {@link Pattern} directly in your tests
 * then you can create a class resembling this one. It can
 * contain all the {@link Pattern} you want to use in the DSL.
 *
 * &lt;pre&gt;
 * {@code
 * request {
 *     body(
 *         [ age: $(c(PatternUtils.oldEnough()))]
 *     )
 * }
 * &lt;/pre&gt;
 *
 * Notice that we're using both {@code $()} for dynamic values
 * and {@code c()} for the consumer side.
 *
 * @author Marcin Grzejszczak
 */
//tag::impl[]
public class PatternUtils {

	public static String tooYoung() {
		//remove::start[]
		return "[0-1][0-9]";
		//remove::end[return]
	}

	public static Pattern oldEnough() {
		//remove::start[]
		return Pattern.compile("[2-9][0-9]");
		//remove::end[return]
	}

	/**
	 * Makes little sense but it's just an example ;)
	 */
	public static Pattern ok() {
		//remove::start[]
		return Pattern.compile("OK");
		//remove::end[return]
	}
}
//end::impl[]</programlisting>
<simpara><emphasis role="strong">ConsumerUtils</emphasis> contains functions used by the <emphasis role="strong">consumer</emphasis>.</simpara>
<programlisting language="java" linenumbering="unnumbered">package com.example;

import org.springframework.cloud.contract.spec.internal.ClientDslProperty;

/**
 * DSL Properties passed to the DSL from the consumer's perspective.
 * That means that on the input side {@code Request} for HTTP
 * or {@code Input} for messaging you can have a regular expression.
 * On the {@code Response} for HTTP or {@code Output} for messaging
 * you have to have a concrete value.
 *
 * @author Marcin Grzejszczak
 */
//tag::impl[]
public class ConsumerUtils {
	/**
	 * Consumer side property. By using the {@link ClientDslProperty}
	 * you can omit most of boilerplate code from the perspective
	 * of dynamic values. Example
	 *
	 * &lt;pre&gt;
	 * {@code
	 * request {
	 *     body(
	 *         [ age: $(ConsumerUtils.oldEnough())]
	 *     )
	 * }
	 * &lt;/pre&gt;
	 *
	 * That way it's in the implementation that we decide what value we will pass to the consumer
	 * and which one to the producer.
	 *
	 * @author Marcin Grzejszczak
	 */
	public static ClientDslProperty oldEnough() {
		//remove::start[]
		// this example is not the best one and
		// theoretically you could just pass the regex instead of `ServerDslProperty` but
		// it's just to show some new tricks :)
		return new ClientDslProperty(PatternUtils.oldEnough(), 40);
		//remove::end[return]
	}

}
//end::impl[]</programlisting>
<simpara><emphasis role="strong">ProducerUtils</emphasis> contains functions used by the <emphasis role="strong">producer</emphasis>.</simpara>
<programlisting language="java" linenumbering="unnumbered">package com.example;

import org.springframework.cloud.contract.spec.internal.ServerDslProperty;

/**
 * DSL Properties passed to the DSL from the producer's perspective.
 * That means that on the input side {@code Request} for HTTP
 * or {@code Input} for messaging you have to have a concrete value.
 * On the {@code Response} for HTTP or {@code Output} for messaging
 * you can have a regular expression.
 *
 * @author Marcin Grzejszczak
 */
//tag::impl[]
public class ProducerUtils {

	/**
	 * Producer side property. By using the {@link ProducerUtils}
	 * you can omit most of boilerplate code from the perspective
	 * of dynamic values. Example
	 *
	 * &lt;pre&gt;
	 * {@code
	 * response {
	 *     body(
	 *         [ status: $(ProducerUtils.ok())]
	 *     )
	 * }
	 * &lt;/pre&gt;
	 *
	 * That way it's in the implementation that we decide what value we will pass to the consumer
	 * and which one to the producer.
	 */
	public static ServerDslProperty ok() {
		// this example is not the best one and
		// theoretically you could just pass the regex instead of `ServerDslProperty` but
		// it's just to show some new tricks :)
		return new ServerDslProperty( PatternUtils.ok(), "OK");
	}
}
//end::impl[]</programlisting>
</section>
<section xml:id="_adding_the_dependency_to_the_project">
<title>Adding the Dependency to the Project</title>
<simpara>In order for the plugins and IDE to be able to reference the common JAR classes, you need
to pass the dependency to your project.</simpara>
</section>
<section xml:id="_test_the_dependency_in_the_project_s_dependencies">
<title>Test the Dependency in the Project&#8217;s Dependencies</title>
<simpara>First, add the common jar dependency as a test dependency. Because your contracts files
are available on the test resources path,  the common jar classes automatically become
visible in your Groovy files. The following examples show how to test the dependency:</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
	&lt;groupId&gt;com.example&lt;/groupId&gt;
	&lt;artifactId&gt;beer-common&lt;/artifactId&gt;
	&lt;version&gt;${project.version}&lt;/version&gt;
	&lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">testCompile("com.example:beer-common:0.0.1-SNAPSHOT")</programlisting>
</para>
</formalpara>
</section>
<section xml:id="_test_a_dependency_in_the_plugin_s_dependencies">
<title>Test a Dependency in the Plugin&#8217;s Dependencies</title>
<simpara>Now, you must add the dependency for the plugin to reuse at runtime, as shown in the
following example:</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
	&lt;extensions&gt;true&lt;/extensions&gt;
	&lt;configuration&gt;
		&lt;packageWithBaseClasses&gt;com.example&lt;/packageWithBaseClasses&gt;
		&lt;baseClassMappings&gt;
			&lt;baseClassMapping&gt;
				&lt;contractPackageRegex&gt;.*intoxication.*&lt;/contractPackageRegex&gt;
				&lt;baseClassFQN&gt;com.example.intoxication.BeerIntoxicationBase&lt;/baseClassFQN&gt;
			&lt;/baseClassMapping&gt;
		&lt;/baseClassMappings&gt;
	&lt;/configuration&gt;
	&lt;dependencies&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;com.example&lt;/groupId&gt;
			&lt;artifactId&gt;beer-common&lt;/artifactId&gt;
			&lt;version&gt;${project.version}&lt;/version&gt;
			&lt;scope&gt;compile&lt;/scope&gt;
		&lt;/dependency&gt;
	&lt;/dependencies&gt;
&lt;/plugin&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">classpath "com.example:beer-common:0.0.1-SNAPSHOT"</programlisting>
</para>
</formalpara>
</section>
<section xml:id="_referencing_classes_in_dsls">
<title>Referencing classes in DSLs</title>
<simpara>You can now reference your classes in your DSL, as shown in the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package contracts.beer.rest

import com.example.ConsumerUtils
import com.example.ProducerUtils
import org.springframework.cloud.contract.spec.Contract

Contract.make {
	description("""
Represents a successful scenario of getting a beer

```
given:
	client is old enough
when:
	he applies for a beer
then:
	we'll grant him the beer
```

""")
	request {
		method 'POST'
		url '/check'
		body(
				age: $(ConsumerUtils.oldEnough())
		)
		headers {
			contentType(applicationJson())
		}
	}
	response {
		status 200
		body("""
			{
				"status": "${value(ProducerUtils.ok())}"
			}
			""")
		headers {
			contentType(applicationJson())
		}
	}
}</programlisting>
</section>
</section>
</chapter>
<chapter xml:id="_using_the_pluggable_architecture">
<title>Using the Pluggable Architecture</title>
<simpara>You may encounter cases where you have your contracts have been defined in other formats,
such as YAML, RAML or PACT. In those cases, you still want to benefit from the automatic
generation of tests and stubs. You can add your own implementation for generating both
tests and stubs. Also, you can customize the way tests are generated (for example, you
can generate tests for other languages) and the way stubs are generated (for example, you
can generate stubs for other HTTP server implementations).</simpara>
<section xml:id="_custom_contract_converter">
<title>Custom Contract Converter</title>
<simpara>Assume that your contract is written in a YAML file as follows:</simpara>
<programlisting language="yml" linenumbering="unnumbered">request:
  url: /foo
  method: PUT
  headers:
    foo: bar
  body:
    foo: bar
response:
  status: 200
  headers:
    foo2: bar
  body:
    foo2: bar</programlisting>
<simpara>The <literal>ContractConverter</literal> interface lets you register your own implementation of a contract
structure converter. The following code listing shows the <literal>ContractConverter</literal> interface:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.spec

/**
 * Converter to be used to convert FROM {@link File} TO {@link Contract}
 * and from {@link Contract} to {@code T}
 *
 * @param &lt;T&gt; - type to which we want to convert the contract
 *
 * @author Marcin Grzejszczak
 * @since 1.1.0
 */
interface ContractConverter&lt;T&gt; {

	/**
	 * Should this file be accepted by the converter. Can use the file extension
	 * to check if the conversion is possible.
	 *
	 * @param file - file to be considered for conversion
	 * @return - {@code true} if the given implementation can convert the file
	 */
	boolean isAccepted(File file)

	/**
	 * Converts the given {@link File} to its {@link Contract} representation
	 *
	 * @param file - file to convert
	 * @return - {@link Contract} representation of the file
	 */
	Collection&lt;Contract&gt; convertFrom(File file)

	/**
	 * Converts the given {@link Contract} to a {@link T} representation
	 *
	 * @param contract - the parsed contract
	 * @return - {@link T} the type to which we do the conversion
	 */
	T convertTo(Collection&lt;Contract&gt; contract)
}</programlisting>
<simpara>Your implementation must define the condition on which it should start the
conversion. Also, you must define how to perform that conversion in both directions.</simpara>
<important>
<simpara>Once you create your implementation, you must create a
<literal>/META-INF/spring.factories</literal> file in which you provide the fully qualified name of your
implementation.</simpara>
</important>
<simpara>The following example shows a typical <literal>spring.factories</literal> file:</simpara>
<screen># Converters
org.springframework.cloud.contract.spec.ContractConverter=\
org.springframework.cloud.contract.verifier.converter.YamlContractConverter</screen>
<simpara>The following example shows a typical YAML implementation that matches the preceding
example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.verifier.converter

import java.nio.file.Files

import groovy.transform.CompileStatic
import org.springframework.cloud.contract.spec.Contract
import org.springframework.cloud.contract.spec.ContractConverter
import org.springframework.cloud.contract.spec.internal.Headers
import org.yaml.snakeyaml.Yaml

/**
 * Simple converter from and to a {@link YamlContract} to a collection of {@link Contract}
 */
@CompileStatic
class YamlContractConverter implements ContractConverter&lt;List&lt;YamlContract&gt;&gt; {

	@Override
	public boolean isAccepted(File file) {
		String name = file.getName()
		return name.endsWith(".yml") || name.endsWith(".yaml")
	}

	@Override
	public Collection&lt;Contract&gt; convertFrom(File file) {
		try {
			YamlContract yamlContract = new Yaml().loadAs(
					Files.newInputStream(file.toPath()), YamlContract.class)
			return [Contract.make {
				request {
					method(yamlContract?.request?.method)
					url(yamlContract?.request?.url)
					headers {
						yamlContract?.request?.headers?.each { String key, Object value -&gt;
							header(key, value)
						}
					}
					body(yamlContract?.request?.body)
				}
				response {
					status(yamlContract?.response?.status)
					headers {
						yamlContract?.response?.headers?.each { String key, Object value -&gt;
							header(key, value)
						}
					}
					body(yamlContract?.response?.body)
				}
			}]
		}
		catch (FileNotFoundException e) {
			throw new IllegalStateException(e)
		}
	}

	@Override
	public List&lt;YamlContract&gt; convertTo(Collection&lt;Contract&gt; contracts) {
		return contracts.collect { Contract contract -&gt;
			YamlContract yamlContract = new YamlContract()
			yamlContract.request.with {
				method = contract?.request?.method?.clientValue
				url = contract?.request?.url?.clientValue
				headers = (contract?.request?.headers as Headers)?.asStubSideMap()
				body = contract?.request?.body?.clientValue as Map
			}
			yamlContract.response.with {
				status = contract?.response?.status?.clientValue as Integer
				headers = (contract?.response?.headers as Headers)?.asStubSideMap()
				body = contract?.response?.body?.clientValue as Map
			}
			return yamlContract
		}
	}
}</programlisting>
<section xml:id="_pact_converter">
<title>Pact Converter</title>
<simpara>Spring Cloud Contract includes support for <link xl:href="https://docs.pact.io/">Pact</link> representation of
contracts. Instead of using the Groovy DSL, you can use Pact files. In this section, we
present how to add Pact support for your project.</simpara>
</section>
<section xml:id="_pact_contract">
<title>Pact Contract</title>
<simpara>Consider following example of a Pact contract, which is a file under the
<literal>src/test/resources/contracts</literal> folder.</simpara>
<programlisting language="javascript" linenumbering="unnumbered">{
  "provider": {
    "name": "Provider"
  },
  "consumer": {
    "name": "Consumer"
  },
  "interactions": [
    {
      "description": "",
      "request": {
        "method": "PUT",
        "path": "/fraudcheck",
        "headers": {
          "Content-Type": "application/vnd.fraud.v1+json"
        },
        "body": {
          "clientId": "1234567890",
          "loanAmount": 99999
        },
        "matchingRules": {
          "$.body.clientId": {
            "match": "regex",
            "regex": "[0-9]{10}"
          }
        }
      },
      "response": {
        "status": 200,
        "headers": {
          "Content-Type": "application/vnd.fraud.v1+json;charset=UTF-8"
        },
        "body": {
          "fraudCheckStatus": "FRAUD",
          "rejectionReason": "Amount too high"
        },
        "matchingRules": {
          "$.body.fraudCheckStatus": {
            "match": "regex",
            "regex": "FRAUD"
          }
        }
      }
    }
  ],
  "metadata": {
    "pact-specification": {
      "version": "2.0.0"
    },
    "pact-jvm": {
      "version": "2.4.18"
    }
  }
}</programlisting>
<simpara>The remainder of this section about using Pact refers to the preceding file.</simpara>
</section>
<section xml:id="_pact_for_producers">
<title>Pact for Producers</title>
<simpara>On the producer side, you mustadd two additional dependencies to your plugin
configuration. One is the Spring Cloud Contract Pact support, and the other represents
the current Pact version that you use.</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;plugin&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-maven-plugin&lt;/artifactId&gt;
	&lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
	&lt;extensions&gt;true&lt;/extensions&gt;
	&lt;configuration&gt;
		&lt;packageWithBaseClasses&gt;com.example.fraud&lt;/packageWithBaseClasses&gt;
	&lt;/configuration&gt;
	&lt;dependencies&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
			&lt;artifactId&gt;spring-cloud-contract-spec-pact&lt;/artifactId&gt;
			&lt;version&gt;${spring-cloud-contract.version}&lt;/version&gt;
		&lt;/dependency&gt;
		&lt;dependency&gt;
			&lt;groupId&gt;au.com.dius&lt;/groupId&gt;
			&lt;artifactId&gt;pact-jvm-model&lt;/artifactId&gt;
			&lt;version&gt;2.4.18&lt;/version&gt;
		&lt;/dependency&gt;
	&lt;/dependencies&gt;
&lt;/plugin&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">classpath "org.springframework.cloud:spring-cloud-contract-spec-pact:${findProperty('verifierVersion') ?: verifierVersion}"
classpath 'au.com.dius:pact-jvm-model:2.4.18'</programlisting>
</para>
</formalpara>
<simpara>When you execute the build of your application, a test will be generated. The generated
test might be as follows:</simpara>
<programlisting language="java" linenumbering="unnumbered">@Test
public void validate_shouldMarkClientAsFraud() throws Exception {
	// given:
		MockMvcRequestSpecification request = given()
				.header("Content-Type", "application/vnd.fraud.v1+json")
				.body("{\"clientId\":\"1234567890\",\"loanAmount\":99999}");

	// when:
		ResponseOptions response = given().spec(request)
				.put("/fraudcheck");

	// then:
		assertThat(response.statusCode()).isEqualTo(200);
		assertThat(response.header("Content-Type")).isEqualTo("application/vnd.fraud.v1+json;charset=UTF-8");
	// and:
		DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
		assertThatJson(parsedJson).field("rejectionReason").isEqualTo("Amount too high");
	// and:
		assertThat(parsedJson.read("$.fraudCheckStatus", String.class)).matches("FRAUD");
}</programlisting>
<simpara>The corresponding generated stub might be as follows:</simpara>
<programlisting language="javascript" linenumbering="unnumbered">{
  "uuid" : "996ae5ae-6834-4db6-8fac-358ca187ab62",
  "request" : {
    "url" : "/fraudcheck",
    "method" : "PUT",
    "headers" : {
      "Content-Type" : {
        "equalTo" : "application/vnd.fraud.v1+json"
      }
    },
    "bodyPatterns" : [ {
      "matchesJsonPath" : "$[?(@.loanAmount == 99999)]"
    }, {
      "matchesJsonPath" : "$[?(@.clientId =~ /([0-9]{10})/)]"
    } ]
  },
  "response" : {
    "status" : 200,
    "body" : "{\"fraudCheckStatus\":\"FRAUD\",\"rejectionReason\":\"Amount too high\"}",
    "headers" : {
      "Content-Type" : "application/vnd.fraud.v1+json;charset=UTF-8"
    }
  }
}</programlisting>
</section>
<section xml:id="_pact_for_consumers">
<title>Pact for Consumers</title>
<simpara>On the producer side, you must add two additional dependencies to your project
dependencies. One is the Spring Cloud Contract Pact support, and the other represents the
current Pact version that you use.</simpara>
<formalpara role="primary">
<title>Maven</title>
<para>
<programlisting language="xml" linenumbering="unnumbered">&lt;dependency&gt;
	&lt;groupId&gt;org.springframework.cloud&lt;/groupId&gt;
	&lt;artifactId&gt;spring-cloud-contract-spec-pact&lt;/artifactId&gt;
	&lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;
&lt;dependency&gt;
	&lt;groupId&gt;au.com.dius&lt;/groupId&gt;
	&lt;artifactId&gt;pact-jvm-model&lt;/artifactId&gt;
	&lt;version&gt;2.4.18&lt;/version&gt;
	&lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;</programlisting>
</para>
</formalpara>
<formalpara role="secondary">
<title>Gradle</title>
<para>
<programlisting language="groovy" linenumbering="unnumbered">testCompile "org.springframework.cloud:spring-cloud-contract-spec-pact"
testCompile 'au.com.dius:pact-jvm-model:2.4.18'</programlisting>
</para>
</formalpara>
</section>
</section>
<section xml:id="_using_the_custom_test_generator">
<title>Using the Custom Test Generator</title>
<simpara>If you want to generate tests for languages other than Java or you are not happy with the
way the verifier builds Java tests, you can register your own implementation.</simpara>
<simpara>The <literal>SingleTestGenerator</literal> interface lets you register your own implementation.  The
following code listing shows the <literal>SingleTestGenerator</literal> interface:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.verifier.builder

import org.springframework.cloud.contract.verifier.config.ContractVerifierConfigProperties
import org.springframework.cloud.contract.verifier.file.ContractMetadata
/**
 * Builds a single test.
 *
 * @since 1.1.0
 */
interface SingleTestGenerator {

	/**
	 * Creates contents of a single test class in which all test scenarios from
	 * the contract metadata should be placed.
	 *
	 * @param properties - properties passed to the plugin
	 * @param listOfFiles - list of parsed contracts with additional metadata
	 * @param className - the name of the generated test class
	 * @param classPackage - the name of the package in which the test class should be stored
	 * @param includedDirectoryRelativePath - relative path to the included directory
	 * @return contents of a single test class
	 */
	String buildClass(ContractVerifierConfigProperties properties, Collection&lt;ContractMetadata&gt; listOfFiles,
					  String className, String classPackage, String includedDirectoryRelativePath)

	/**
	 * Extension that should be appended to the generated test class. E.g. {@code .java} or {@code .php}
	 *
	 * @param properties - properties passed to the plugin
	 */
	String fileExtension(ContractVerifierConfigProperties properties)
}</programlisting>
<simpara>Again, you must provide a <literal>spring.factories</literal> file, such as the one shown in the following
example:</simpara>
<screen>org.springframework.cloud.contract.verifier.builder.SingleTestGenerator=/
com.example.MyGenerator</screen>
</section>
<section xml:id="_using_the_custom_stub_generator">
<title>Using the Custom Stub Generator</title>
<simpara>If you want to generate stubs for stub servers other than WireMock, you can plug in your
own implementation of the <literal>StubGenerator</literal> interface. The following code listing shows the
<literal>StubGenerator</literal> interface:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.verifier.converter

import groovy.transform.CompileStatic
import org.springframework.cloud.contract.spec.Contract
import org.springframework.cloud.contract.verifier.file.ContractMetadata

/**
 * Converts contracts into their stub representation.
 *
 * @since 1.1.0
 */
@CompileStatic
interface StubGenerator {

	/**
	 * Returns {@code true} if the converter can handle the file to convert it into a stub.
	 */
	boolean canHandleFileName(String fileName)

	/**
	 * Returns the collection of converted contracts into stubs. One contract can
	 * result in multiple stubs.
	 */
	Map&lt;Contract, String&gt; convertContents(String rootName, ContractMetadata content)

	/**
	 * Returns the name of the converted stub file. If you have multiple contracts
	 * in a single file then a prefix will be added to the generated file. If you
	 * provide the {@link Contract#name} field then that field will override the
	 * generated file name.
	 *
	 * Example: name of file with 2 contracts is {@code foo.groovy}, it will be
	 * converted by the implementation to {@code foo.json}. The recursive file
	 * converter will create two files {@code 0_foo.json} and {@code 1_foo.json}
	 */
	String generateOutputFileNameForInput(String inputFileName)
}</programlisting>
<simpara>Again, you must provide a <literal>spring.factories</literal> file, such as the one shown in the following
example:</simpara>
<screen># Stub converters
org.springframework.cloud.contract.verifier.converter.StubGenerator=\
org.springframework.cloud.contract.verifier.wiremock.DslToWireMockClientConverter</screen>
<simpara>The default implementation is the WireMock stub generation.</simpara>
<tip>
<simpara>You can provide multiple stub generator implementations. For example, from a single
DSL, you can produce both WireMock stubs and Pact files.</simpara>
</tip>
</section>
<section xml:id="_using_the_custom_stub_runner">
<title>Using the Custom Stub Runner</title>
<simpara>If you decide to use a custom stub generation, you also need a custom way of running
stubs with your different stub provider.</simpara>
<simpara>Assume that you use <link xl:href="https://github.com/dreamhead/moco">Moco</link> to build your stubs and that
you have written a stub generator and placed your stubs in a JAR file.</simpara>
<simpara>In order for Stub Runner to know how to run your stubs, you have to define a custom
HTTP Stub server implementation, which might resemble the following example:</simpara>
<programlisting language="groovy" linenumbering="unnumbered">package org.springframework.cloud.contract.stubrunner.provider.moco

import com.github.dreamhead.moco.bootstrap.arg.HttpArgs
import com.github.dreamhead.moco.runner.JsonRunner
import com.github.dreamhead.moco.runner.RunnerSetting
import groovy.util.logging.Slf4j
import org.springframework.cloud.contract.stubrunner.HttpServerStub
import org.springframework.util.SocketUtils

@Slf4j
class MocoHttpServerStub implements HttpServerStub {

	private boolean started
	private JsonRunner runner
	private int port

	@Override
	int port() {
		if (!isRunning()) {
			return -1
		}
		return port
	}

	@Override
	boolean isRunning() {
		return started
	}

	@Override
	HttpServerStub start() {
		return start(SocketUtils.findAvailableTcpPort())
	}

	@Override
	HttpServerStub start(int port) {
		this.port = port
		return this
	}

	@Override
	HttpServerStub stop() {
		if (!isRunning()) {
			return this
		}
		this.runner.stop()
		return this
	}

	@Override
	HttpServerStub registerMappings(Collection&lt;File&gt; stubFiles) {
		List&lt;RunnerSetting&gt; settings = stubFiles.findAll { it.name.endsWith("json") }
				.collect {
			log.info("Trying to parse [{}]", it.name)
			try {
				return RunnerSetting.aRunnerSetting().withStream(it.newInputStream()).build()
			} catch (Exception e) {
				log.warn("Exception occurred while trying to parse file [{}]", it.name, e)
				return null
			}
		}.findAll { it }
		this.runner = JsonRunner.newJsonRunnerWithSetting(settings,
				HttpArgs.httpArgs().withPort(this.port).build())
		this.runner.run()
		this.started = true
		return this
	}

	@Override
	boolean isAccepted(File file) {
		return file.name.endsWith(".json")
	}
}</programlisting>
<simpara>Then, you can register it in your <literal>spring.factories</literal> file, as shown in the following
example:</simpara>
<screen>org.springframework.cloud.contract.stubrunner.HttpServerStub=\
org.springframework.cloud.contract.stubrunner.provider.moco.MocoHttpServerStub</screen>
<simpara>Now you can run stubs with Moco.</simpara>
<important>
<simpara>If you do not provide any implementation, then the default (WireMock)
implementation is used. If you provide more than one, the first one on the list is used.</simpara>
</important>
</section>
<section xml:id="_using_the_custom_stub_downloader">
<title>Using the Custom Stub Downloader</title>
<simpara>You can customize the way your stubs are downloaded by creating an implementation of the
<literal>StubDownloaderBuilder</literal> interface, as shown in the following example:</simpara>
<programlisting language="java" linenumbering="unnumbered">package com.example;

class CustomStubDownloaderBuilder implements StubDownloaderBuilder {

	@Override
	public StubDownloader build(final StubRunnerOptions stubRunnerOptions) {
		return new StubDownloader() {
			@Override
			public Map.Entry&lt;StubConfiguration, File&gt; downloadAndUnpackStubJar(
					StubConfiguration config) {
				File unpackedStubs = retrieveStubs();
				return new AbstractMap.SimpleEntry&lt;&gt;(
						new StubConfiguration(config.getGroupId(), config.getArtifactId(), version,
								config.getClassifier()), unpackedStubs);
			}

			File retrieveStubs() {
			    // here goes your custom logic to provide a folder where all the stubs reside
			}
}</programlisting>
<simpara>Then you can register it in your <literal>spring.factories</literal> file, as shown in the following
example:</simpara>
<screen># Example of a custom Stub Downloader Provider
org.springframework.cloud.contract.stubrunner.StubDownloaderBuilder=\
com.example.CustomStubDownloaderBuilder</screen>
<simpara>Now you can pick a folder with the source of your stubs.</simpara>
<important>
<simpara>If you do not provide any implementation, then the default is used.
If you use the <literal>repositoryRoot</literal> property or the <literal>workOffline</literal> flag, then an Aether-based
implementation that downloads stubs from a remote repository is used. If you do not
provide these values, the <literal>ClasspathStubProvider</literal> (which will scan the classpath) is
used. If you provide more than one, then the first one on the list is used.</simpara>
</important>
</section>
</chapter>
<chapter xml:id="_spring_cloud_contract_wiremock">
<title>Spring Cloud Contract WireMock</title>
<simpara>Modules giving you the possibility to use
<link xl:href="http://wiremock.org">WireMock</link> with different servers by using the
"ambient" server embedded in a Spring Boot application. Check out the
<link xl:href="https://github.com/spring-cloud/spring-cloud-contract/tree/1.0.x/samples">samples</link>
for more details.</simpara>
<important>
<simpara>The Spring Cloud Release Train BOM imports <literal>spring-cloud-contract-dependencies</literal>
 which in turn has exclusions for the dependencies needed by WireMock. This might lead to a situation that
 even if you&#8217;re not using Spring Cloud Contract then your dependencies will be influenced
 anyways.</simpara>
</important>
<simpara>If you have a Spring Boot application that uses Tomcat as an embedded
server, for example (the default with <literal>spring-boot-starter-web</literal>), then
you can simply add <literal>spring-cloud-contract-wiremock</literal> to your classpath
and add <literal>@AutoConfigureWireMock</literal> in order to be able to use Wiremock
in your tests. Wiremock runs as a stub server and you can register
stub behaviour using a Java API or via static JSON declarations as
part of your test. Here&#8217;s a simple example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
@AutoConfigureWireMock(port = 0)
public class WiremockForDocsTests {
	// A service that calls out over HTTP
	@Autowired private Service service;

	// Using the WireMock APIs in the normal way:
	@Test
	public void contextLoads() throws Exception {
		// Stubbing WireMock
		stubFor(get(urlEqualTo("/resource"))
				.willReturn(aResponse().withHeader("Content-Type", "text/plain").withBody("Hello World!")));
		// We're asserting if WireMock responded properly
		assertThat(this.service.go()).isEqualTo("Hello World!");
	}

}</programlisting>
<simpara>To start the stub server on a different port use <literal>@AutoConfigureWireMock(port=9999)</literal> (for example), and for a random port use the value 0. The stub server port will be bindable in the test application context as "wiremock.server.port". Using <literal>@AutoConfigureWireMock</literal> adds a bean of type <literal>WiremockConfiguration</literal> to your test application context, where it will be cached in between methods and classes having the same context, just like for normal Spring integration tests.</simpara>
<section xml:id="_registering_stubs_automatically">
<title>Registering Stubs Automatically</title>
<simpara>If you use <literal>@AutoConfigureWireMock</literal> then it will register WireMock
JSON stubs from the file system or classpath, by default from
<literal>file:src/test/resources/mappings</literal>. You can customize the locations
using the <literal>stubs</literal> attribute in the annotation, which can be a resource
pattern (ant-style) or a directory, in which case <literal><emphasis role="strong">*/</emphasis>.json</literal> is
appended. Example:</simpara>
<screen>@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureWireMock(stubs="classpath:/stubs")
public class WiremockImportApplicationTests {

	@Autowired
	private Service service;

	@Test
	public void contextLoads() throws Exception {
		assertThat(this.service.go()).isEqualTo("Hello World!");
	}

}</screen>
<note>
<simpara>Actually WireMock always loads mappings from
<literal>src/test/resources/mappings</literal> <emphasis role="strong">as well as</emphasis> the custom locations in the
stubs attribute. To change this behaviour you have to also specify a
files root as described next.</simpara>
</note>
</section>
<section xml:id="_using_files_to_specify_the_stub_bodies">
<title>Using Files to Specify the Stub Bodies</title>
<simpara>WireMock can read response bodies from files on the classpath or file
system. In that case you will see in the JSON DSL that the response
has a "bodyFileName" instead of a (literal) "body". The files are
resolved relative to a root directory <literal>src/test/resources/__files</literal> by
default. To customize this location you can set the <literal>files</literal> attribute
in the <literal>@AutoConfigureWireMock</literal> annotation to the location of the
parent directory (i.e. the place <literal>__files</literal> is a
subdirectory). You can use Spring resource notation to refer to
<literal>file:&#8230;&#8203;</literal> or <literal>classpath:&#8230;&#8203;</literal> locations (but generic URLs are not
supported). A list of values can be given and WireMock will resolve
the first file that exists when it needs to find a response body.</simpara>
<note>
<simpara>when you configure the <literal>files</literal> root, then it affects the
automatic loading of stubs as well (they come from the root location
in a subdirectory called "mappings"). The value of <literal>files</literal> has no
effect on the stubs loaded explicitly from the <literal>stubs</literal> attribute.</simpara>
</note>
</section>
<section xml:id="_alternative_using_junit_rules">
<title>Alternative: Using JUnit Rules</title>
<simpara>For a more conventional WireMock experience, using JUnit <literal>@Rules</literal> to
start and stop the server, just use the <literal>WireMockSpring</literal> convenience
class to obtain an <literal>Options</literal> instance:</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
public class WiremockForDocsClassRuleTests {

	// Start WireMock on some dynamic port
	// for some reason `dynamicPort()` is not working properly
	@ClassRule
	public static WireMockClassRule wiremock = new WireMockClassRule(
			WireMockSpring.options().dynamicPort());
	// A service that calls out over HTTP to localhost:${wiremock.port}
	@Autowired
	private Service service;

	// Using the WireMock APIs in the normal way:
	@Test
	public void contextLoads() throws Exception {
		// Stubbing WireMock
		wiremock.stubFor(get(urlEqualTo("/resource"))
				.willReturn(aResponse().withHeader("Content-Type", "text/plain").withBody("Hello World!")));
		// We're asserting if WireMock responded properly
		assertThat(this.service.go()).isEqualTo("Hello World!");
	}

}</programlisting>
<simpara>The use <literal>@ClassRule</literal> means that the server will shut down after all the methods in this class.</simpara>
</section>
<section xml:id="_relaxed_ssl_validation_for_rest_template">
<title>Relaxed SSL Validation for Rest Template</title>
<simpara>WireMock allows you to stub a "secure" server with an "https" URL protocol. If your application wants to
contact that stub server in an integration test, then it will find that the SSL certificates are not
valid (it&#8217;s the usual problem with self-installed certificates). The best option is often to just
re-configure the client to use "http", but if that&#8217;s not open to you then you can ask Spring to configure
an HTTP client that ignores SSL validation errors (just for tests).</simpara>
<simpara>To make this work with minimum fuss you need to be using the Spring Boot <literal>RestTemplateBuilder</literal> in your app,
e.g.</simpara>
<programlisting language="java" linenumbering="unnumbered">@Bean
public RestTemplate restTemplate(RestTemplateBuilder builder) {
	return builder.build();
}</programlisting>
<simpara>This is because the builder is passed through callbacks to initalize it, so the SSL validation can be set up
in the client at that point. This will happen automatically in your test if you are using the
<literal>@AutoConfigureWireMock</literal> annotation (or the stub runner). If you are using the JUnit <literal>@Rule</literal> approach you need
to add the <literal>@AutoConfigureHttpClient</literal> annotation as well:</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest("app.baseUrl=https://localhost:6443")
@AutoConfigureHttpClient
public class WiremockHttpsServerApplicationTests {

	@ClassRule
	public static WireMockClassRule wiremock = new WireMockClassRule(
			WireMockSpring.options().httpsPort(6443));
...
}</programlisting>
<simpara>If you are using <literal>spring-boot-starter-test</literal> then you will have the Apache HTTP client on the classpath and it will
be selected by the <literal>RestTemplateBuilder</literal> and configured to ignore SSL errors. If you are using the default <literal>java.net</literal>
client you don&#8217;t need the annotation (but it won&#8217;t do any harm). There is no support currently for other clients, but
it may be added in future releases.</simpara>
</section>
<section xml:id="_wiremock_and_spring_mvc_mocks">
<title>WireMock and Spring MVC Mocks</title>
<simpara>Spring Cloud Contract provides a convenience class that can load JSON WireMock stubs into a
Spring <literal>MockRestServiceServer</literal>. Here&#8217;s an example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment = WebEnvironment.NONE)
public class WiremockForDocsMockServerApplicationTests {

	@Autowired
	private RestTemplate restTemplate;

	@Autowired
	private Service service;

	@Test
	public void contextLoads() throws Exception {
		// will read stubs classpath
		MockRestServiceServer server = WireMockRestServiceServer.with(this.restTemplate)
				.baseUrl("https://example.org").stubs("classpath:/stubs/resource.json")
				.build();
		// We're asserting if WireMock responded properly
		assertThat(this.service.go()).isEqualTo("Hello World");
		server.verify();
	}
}</programlisting>
<simpara>The <literal>baseUrl</literal> is prepended to all mock calls, and the <literal>stubs()</literal>
method takes a stub path resource pattern as an argument. So in this
example the stub defined at <literal>/stubs/resource.json</literal> is loaded into the
mock server, so if the <literal>RestTemplate</literal> is asked to visit
<literal><link xl:href="https://example.org/">https://example.org/</link></literal> it will get the responses as declared
there. More than one stub pattern can be specified, and each one can
be a directory (for a recursive list of all ".json"), or a fixed
filename (like in the example above) or an ant-style pattern. The JSON
format is the normal WireMock format which you can read about in the
WireMock website.</simpara>
<simpara>Currently we support Tomcat, Jetty and Undertow as Spring Boot
embedded servers, and Wiremock itself has "native" support for a
particular version of Jetty (currently 9.2). To use the native Jetty
you need to add the native wiremock dependencies and exclude the
Spring Boot container if there is one.</simpara>
</section>
<section xml:id="_generating_stubs_using_restdocs">
<title>Generating Stubs using RestDocs</title>
<simpara><link xl:href="https://projects.spring.io/spring-restdocs">Spring RestDocs</link> can be
used to generate documentation (e.g. in asciidoctor format) for an
HTTP API with Spring MockMvc or Rest Assured. At the same time as you
generate documentation for your API, you can also generate WireMock
stubs, by using Spring Cloud Contract WireMock. Just write your normal
RestDocs test cases and use <literal>@AutoConfigureRestDocs</literal> to have stubs
automatically in the restdocs output directory. For example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureRestDocs(outputDir = "target/snippets")
@AutoConfigureMockMvc
public class ApplicationTests {

	@Autowired
	private MockMvc mockMvc;

	@Test
	public void contextLoads() throws Exception {
		mockMvc.perform(get("/resource"))
				.andExpect(content().string("Hello World"))
				.andDo(document("resource"));
	}
}</programlisting>
<simpara>From this test will be generated a WireMock stub at
"target/snippets/stubs/resource.json". It matches all GET requests to
the "/resource" path.</simpara>
<simpara>Without any additional configuration this will create a stub with a
request matcher for the HTTP method and all headers except "host" and
"content-length". To match the request more precisely, for example to
match the body of a POST or PUT, we need to explicitly create a
request matcher. This will do two things: 1) create a stub that only
matches the way you specify, 2) assert that the request in the test
case also matches the same conditions.</simpara>
<simpara>The main entry point for this is <literal>WireMockRestDocs.verify()</literal> which can
be used as a substitute for the <literal>document()</literal> convenience method. For
example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@RunWith(SpringRunner.class)
@SpringBootTest
@AutoConfigureRestDocs(outputDir = "target/snippets")
@AutoConfigureMockMvc
public class ApplicationTests {

	@Autowired
	private MockMvc mockMvc;

	@Test
	public void contextLoads() throws Exception {
		mockMvc.perform(post("/resource")
                .content("{\"id\":\"123456\",\"message\":\"Hello World\"}"))
				.andExpect(status().isOk())
				.andDo(verify().jsonPath("$.id")
                        .stub("resource"));
	}
}</programlisting>
<simpara>So this contract is saying: any valid POST with an "id" field will get
back an the same response as in this test. You can chain together
calls to <literal>.jsonPath()</literal> to add additional matchers. The
<link xl:href="https://github.com/jayway/JsonPath">JayWay documentation</link> can help you
to get up to speed with JSON Path if it is unfamiliar to you.</simpara>
<simpara>Instead of the <literal>jsonPath</literal> and <literal>contentType</literal> convenience methods, you
can also use the WireMock APIs to verify the request matches the
created stub. Example:</simpara>
<programlisting language="java" linenumbering="unnumbered">@Test
public void contextLoads() throws Exception {
	mockMvc.perform(post("/resource")
               .content("{\"id\":\"123456\",\"message\":\"Hello World\"}"))
			.andExpect(status().isOk())
			.andDo(verify()
					.wiremock(WireMock.post(
						urlPathEquals("/resource"))
						.withRequestBody(matchingJsonPath("$.id"))
                       .stub("post-resource"));
}</programlisting>
<simpara>The WireMock API is rich - you can match headers, query parameters,
and request body by regex as well as by json path - so this can useful
to create stubs with a wider range of parameters. The above example
will generate a stub something like this:</simpara>
<formalpara>
<title>post-resource.json</title>
<para>
<programlisting language="json" linenumbering="unnumbered">{
  "request" : {
    "url" : "/resource",
    "method" : "POST",
    "bodyPatterns" : [ {
      "matchesJsonPath" : "$.id"
    }]
  },
  "response" : {
    "status" : 200,
    "body" : "Hello World",
    "headers" : {
      "X-Application-Context" : "application:-1",
      "Content-Type" : "text/plain"
    }
  }
}</programlisting>
</para>
</formalpara>
<note>
<simpara>You can use either the <literal>wiremock()</literal> method or the <literal>jsonPath()</literal>
and <literal>contentType()</literal> methods to create request matchers, but not both.</simpara>
</note>
<simpara>On the consumer side, you can make the <literal>resource.json</literal> generated above
available on the classpath (by <link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract.html#_publishing_stubs_as_jars">publishing stubs as JARs</link> for example).
After that, you can create a stub using WireMock in a
number of different ways, including as described above using
<literal>@AutoConfigureWireMock(stubs="classpath:resource.json")</literal>.</simpara>
</section>
<section xml:id="_generating_contracts_using_restdocs">
<title>Generating Contracts using RestDocs</title>
<simpara>Another thing that can be generated with Spring RestDocs is the Spring Cloud
Contract DSL file and documentation. If you combine that with Spring Cloud
WireMock then you&#8217;re getting both the contracts and stubs.</simpara>
<simpara>Why would you want to use this feature? Some people in the community asked questions
about situation in which they would like to move to DSL based contract definition
but they already have a lot of Spring MVC tests. Using this feature allows you to generate
the contract files that you can later modify and move to proper folders so that the
plugin picks them up.</simpara>
<tip>
<simpara>You might wonder why this functionality is in the WireMock module.
Come to think of it, it does make sense since it makes little sense to generate
only contracts and not generate the stubs. That&#8217;s why we suggest to do both.</simpara>
</tip>
<simpara>Let&#8217;s imagine the following test:</simpara>
<programlisting language="java" linenumbering="unnumbered">		this.mockMvc.perform(post("/foo")
					.accept(MediaType.APPLICATION_PDF)
					.accept(MediaType.APPLICATION_JSON)
					.contentType(MediaType.APPLICATION_JSON)
					.content("{\"foo\": 23, \"bar\" : \"baz\" }"))
				.andExpect(status().isOk())
				.andExpect(content().string("bar"))
				// first WireMock
				.andDo(WireMockRestDocs.verify()
						.jsonPath("$[?(@.foo &gt;= 20)]")
						.jsonPath("$[?(@.bar in ['baz','bazz','bazzz'])]")
						.contentType(MediaType.valueOf("application/json"))
						.stub("shouldGrantABeerIfOldEnough"))
				// then Contract DSL documentation
				.andDo(document("index", SpringCloudContractRestDocs.dslContract()));</programlisting>
<simpara>This will lead in the creation of the stub as presented in the previous
section, contract will get generated and a documentation file too.</simpara>
<simpara>The contract will be called <literal>index.groovy</literal> and look more like this.</simpara>
<programlisting language="groovy" linenumbering="unnumbered">import org.springframework.cloud.contract.spec.Contract

Contract.make {
    request {
        method 'POST'
        url '/foo'
        body('''
            {"foo": 23 }
        ''')
        headers {
            header('''Accept''', '''application/json''')
            header('''Content-Type''', '''application/json''')
        }
    }
    response {
        status 200
        body('''
        bar
        ''')
        headers {
            header('''Content-Type''', '''application/json;charset=UTF-8''')
            header('''Content-Length''', '''3''')
        }
        testMatchers {
            jsonPath('$[?(@.foo &gt;= 20)]', byType())
        }
    }
}</programlisting>
<simpara>the generated document (example for Asciidoc) will contain a formatted contract
(the location of this file would be <literal>index/dsl-contract.adoc</literal>).</simpara>
</section>
</chapter>
<chapter xml:id="_links">
<title>Links</title>
<simpara>Here you can find interesting links related to Spring Cloud Contract Verifier:</simpara>
<itemizedlist>
<listitem>
<simpara><link xl:href="https://github.com/spring-cloud/spring-cloud-contract/">Spring Cloud Contract Github Repository</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://github.com/spring-cloud-samples/spring-cloud-contract-samples/">Spring Cloud Contract Samples</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract.html">Spring Cloud Contract Documentation</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract.html/deprecated">Accurest Legacy Documentation</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract.html/#spring-cloud-contract-stub-runner">Spring Cloud Contract Stub Runner Documentation</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract.html/#stub-runner-for-messaging">Spring Cloud Contract Stub Runner Messaging Documentation</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://gitter.im/spring-cloud/spring-cloud-contract">Spring Cloud Contract Gitter</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://cloud.spring.io/spring-cloud-contract/spring-cloud-contract-maven-plugin/">Spring Cloud Contract Maven Plugin</link></simpara>
</listitem>
<listitem>
<simpara><link xl:href="https://www.youtube.com/watch?v=sAAklvxmPmk">Spring Cloud Contract WJUG Presentation by Marcin Grzejszczak</link></simpara>
</listitem>
</itemizedlist>
</chapter>
</book>