Spring Cloud Contract2017-09-04Documentation Authors: Adam Dudczak, Mathias Düsterhöft, Marcin Grzejszczak, Dennis Kieselhorst, Jakub Kubryński, Karol Lassak,
Olga Maciaszek-Sharma, Mariusz Smykuła, Dave Syer1.2.0.BUILD-SNAPSHOTSpring Cloud ContractWhat 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.Spring Cloud Contract Verifier IntroductionThe Accurest project was initially started by Marcin Grzejszczak and Jakub Kubrynski (codearte.io)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 Contract Definition Language (DSL). Contract definitions are used to produce following resources:JSON stub definitions to be used by WireMock when doing integration testing on the client code (client tests).
Test code must still be written by hand, test data is produced by Spring Cloud Contract Verifier.Messaging routes if you’re using one. We’re integrating with Spring Integration, Spring Cloud Stream, Spring AMQP and Apache Camel. You can however set your own integrations if you want toAcceptance tests (in JUnit or Spock) used to verify if server-side implementation of the API is compliant with the contract (server tests).
Full test is generated by Spring Cloud Contract Verifier.Spring Cloud Contract Verifier moves TDD to the level of software architecture.Why?Let us assume that we have a system comprising of multiple microservices:Microservices ArchitectureTesting issuesIf 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:deploy all microservices and perform end to end testsmock other microservices in unit / integration testsBoth have their advantages but also a lot of disadvantages. Let’s focus on the latter.Deploy all microservices and perform end to end testsAdvantages:simulates productiontests real communication between servicesDisadvantages:to test one microservice we would have to deploy 6 microservices, a couple of databases etc.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).long to runvery late feedbackextremely hard to debugMock other microservices in unit / integration testsAdvantages:very fast feedbackno infrastructure requirementsDisadvantages:the implementor of the service creates stubs thus they might have nothing to do with the realityyou can go to production with passing tests and failing productionTo 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.Stubbed ServicesSpring Cloud Contract Verifier gives you the certainty that the stubs that you’re using were created by the service that you’re calling. Also if you can use them it means that they were
tested against the producer’s side. In other words - you can trust those stubs.PurposesThe main purposes of Spring Cloud Contract Verifier with Stub Runner are:to ensure that WireMock / Messaging stubs (used when developing the client) are doing exactly what actual server-side implementation will do,to promote ATDD method and Microservices architectural style,to provide a way to publish changes in contracts that are immediately visible on both sides,to generate boilerplate test code used on the server side.Spring Cloud Contract Verifier’s purpose is NOT to start writing business features in the contracts.
Let’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.HowDefine the contractAs consumers we need to define what exactly we want to achieve. We need to formulate our expectations. That’s why we write the following contract.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.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 200 // (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 `clientId` 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 `clientId` 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.*`
*/Client SideSpring 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.At some point in time you need to send a request to the Fraud Detection service.ResponseEntity<FraudServiceResponse> response =
restTemplate.exchange("http://localhost:" + port + "/fraudcheck", HttpMethod.PUT,
new HttpEntity<>(request, httpHeaders),
FraudServiceResponse.class);Annotate your test class with @AutoConfigureStubRunner. In the annotation provide the group id and artifact id for the Stub Runner to download stubs of your collaborators.@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment=WebEnvironment.NONE)
@AutoConfigureStubRunner(ids = {"com.example:http-server-dsl:+:stubs:6565"}, workOffline = true)
@DirtiesContext
public class LoanApplicationServiceTests {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.Server SideBeing a service Y since you are developing your stub, you need to be sure that it’s actually resembling your
concrete implementation. You can’t have a situation where your stub acts in one way and your application on
production behaves in a different way.That’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.The autogenerated test would look like this:@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");
}Step by step guide to CDCLet’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’t want them to steal the money from us. The current implementation of our system grants loans to everybody.Let’s assume that the Loan Issuance is a client to the
Fraud Detection 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.Technical remark - Fraud Detection will have artifact id http-server, Loan Issuance http-client and both have group id com.example.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.The server side code is available here and the client side code here.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’s repositoryTechnical noteIf using the SNAPSHOT / Milestone / Release Candidate versions please add the following section to yourMaven<repositories>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
<repository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>Gradlerepositories {
mavenCentral()
mavenLocal()
maven { url "http://repo.spring.io/snapshot" }
maven { url "http://repo.spring.io/milestone" }
maven { url "http://repo.spring.io/release" }
}Consumer side (Loan Issuance)As a developer of the Loan Issuance service (a consumer of the Fraud Detection server):start doing TDD by writing a test to your feature@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");
}We’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.write the missing implementationAt some point in time you need to send a request to the Fraud Detection service. 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.ResponseEntity<FraudServiceResponse> response =
restTemplate.exchange("http://localhost:" + port + "/fraudcheck", HttpMethod.PUT,
new HttpEntity<>(request, httpHeaders),
FraudServiceResponse.class);For simplicity we’ve hardcoded the port of the Fraud Detection service at 8080 and our application is running on 8090.If we’d start the written test it would obviously break since we have no service running on port 8080.clone the Fraud Detection service repository locallyWe’ll start playing around with the server side contract. That’s why we need to first clone it.git clone https://your-git-server.com/server-side.git local-http-server-repodefine the contract locally in the repo of Fraud Detection serviceAs consumers we need to define what exactly we want to achieve. We need to formulate our expectations. That’s why we write the following contract.We’re placing the contract under src/test/resources/contracts/fraud folder. The fraud folder
is important cause we’ll reference that folder in the producer’s test base class name.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 200 // (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 `clientId` 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 `clientId` 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.*`
*/The Contract is written using a statically typed Groovy DSL. You might be wondering what are those
value(client(…), server(…)) 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’t want to hardcode a value. You want to allow some different ranges of values. That’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.
Consult the docs
for more information. We highly recommend using the map notation!It’s really important that you understand the map notation to set up contracts. Please read the
Groovy docs regarding JSONThe aforementioned contract is an agreement between two sides that:if an HTTP request is sent witha method PUT on an endpoint /fraudcheckJSON body with client.id matching the regular expression [0-9]{10} and loanAmount equal to 99999and with a header Content-Type equal to application/vnd.fraud.v1+jsonthen an HTTP response would be sent to the consumer thathas status 200contains JSON body with the fraudCheckStatus field containing a value FRAUD and the rejectionReason field having value Amount too highand a Content-Type header with a value of application/vnd.fraud.v1+jsonOnce we’re ready to check the API in practice in the integration tests we need to just install the stubs locallyadd the Spring Cloud Contract Verifier pluginWe can add either Maven or Gradle plugin - in this example we’ll show how to add Maven. First we need to add the Spring Cloud Contract BOM.<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud-dependencies.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>Next, the Spring Cloud Contract Verifier Maven plugin<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<packageWithBaseClasses>com.example.fraud</packageWithBaseClasses>
</configuration>
</plugin>Since the plugin was added we get the Spring Cloud Contract Verifier features which from the provided contracts:generate and run testsproduce and install stubsWe don’t want to generate tests since we, as consumers, want only to play with the stubs. That’s why we need to skip the tests generation and execution. When we execute:cd local-http-server-repo
./mvnw clean install -DskipTestsIn the logs we’ll see something like this:[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:1.5.5.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.jarThis line is extremely important[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.jarIt’s confirming that the stubs of the http-server have been installed in the local repository.run the integration testsIn 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 (Loan Application service).Add the Spring Cloud Contract BOM<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud-dependencies.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>Add the dependency to Spring Cloud Contract Stub Runner<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-contract-stub-runner</artifactId>
<scope>test</scope>
</dependency>Annotate your test class with @AutoConfigureStubRunner. 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’re playing with the collaborators offline (optional step).@RunWith(SpringRunner.class)
@SpringBootTest(webEnvironment=WebEnvironment.NONE)
@AutoConfigureStubRunner(ids = {"com.example:http-server-dsl:+:stubs:6565"}, workOffline = true)
@DirtiesContext
public class LoanApplicationServiceTests {Now if you run your tests you’ll see sth like this: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}]Which means that Stub Runner has found your stubs and started a server for app with group id com.example, artifact id http-server with version 0.0.1-SNAPSHOT of the stubs and with stubs classifier on port 8080.file a PRWhat 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’re happy with the contract.Once we’re satisfied with the results and the test passes publish a PR to the server side. Currently the consumer side work is done.Producer side (Fraud Detection server)As a developer of the Fraud Detection server (a server to the Loan Issuance service):initial implementationAs a reminder here you can see the initial implementation@RequestMapping(value = "/fraudcheck", method = PUT)
public FraudCheckResult fraudCheck(@RequestBody FraudCheck fraudCheck) {
return new FraudCheckResult(FraudCheckStatus.OK, NO_REASON);
}take over the PRgit checkout -b contract-change-pr master
git pull https://your-git-server.com/server-side-fork.git contract-change-prYou have to add the dependencies needed by the autogenerated tests<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-contract-verifier</artifactId>
<scope>test</scope>
</dependency>In the configuration of the Maven plugin we passed the packageWithBaseClasses property<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<packageWithBaseClasses>com.example.fraud</packageWithBaseClasses>
</configuration>
</plugin>We’ve decided to use the "convention based" naming by setting the packageWithBaseClasses 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 src/test/resources/contracts/fraud. Since we don’t have 2 packages starting from the contracts
folder we’re picking only one which is fraud. We’re adding the Base suffix and we’re capitalizing fraud.
That gives us the FraudBase test class name.That’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’re using Rest Assured MVC to start the server side FraudDetectionController.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 -> {
switch (fraudType) {
case DRUNKS:
return 100;
case ALL:
return 200;
}
return 0;
};
}
public void assertThatRejectionReasonIsNull(Object rejectionReason) {
assert rejectionReason == null;
}
}Now, if you run the ./mvnw clean install you would get sth like this:Results :
Tests in error:
ContractVerifierTest.validate_shouldMarkClientAsFraud:32 » IllegalState Parsed...That’s because you have a new contract from which a test was generated and it failed since you haven’t implemented the feature. The autogenerated test would look like this:@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");
}As you can see all the producer() parts of the Contract that were present in the value(consumer(…), producer(…)) blocks got injected into the test.What’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 red part of red, green and refactor. Time to convert the red into the green.write the missing implementationNow since we now what is the expected input and expected output let’s write the missing implementation.@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);
}If we execute ./mvnw clean install again the tests will pass. Since the Spring Cloud Contract Verifier plugin adds the tests to the generated-test-sources you can actually run those tests from your IDE.deploy your appOnce you’ve finished your work it’s time to deploy your change. First merge the branchgit checkout master
git merge --no-ff contract-change-pr
git push origin masterThen we assume that your CI would run sth like ./mvnw clean deploy which would publish both the application and the stub artifcats.Consumer side (Loan Issuance) final stepAs a developer of the Loan Issuance service (a consumer of the Fraud Detection server):merge branch to mastergit checkout master
git merge --no-ff contract-change-prwork onlineNow 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 workOffline parameter in your annotation. Below you can see an
example of achieving the same by changing the properties.stubrunner:
ids: 'com.example:http-server-dsl:+:stubs:8080'
repositoryRoot: http://repo.spring.io/libs-snapshotAnd that’s it!DependenciesThe best way to add the dependencies is to just use the proper starter dependency.For stub-runner use spring-cloud-starter-stub-runner and when you’re using a plugin just add
spring-cloud-starter-contract-verifier.Additional linksBelow 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.Spring Cloud Contract videoYou can check out the video from the Warsaw JUG about Spring Cloud Contract:ReadingsSlides from Marcin Grzejszczak’s talk about AccurestAccurest related articles from Marcin Grzejszczak’s blogSpring Cloud Contract related articles from Marcin Grzejszczak’s blogGroovy docs regarding JSONSamplesHere you can find some samples.Spring Cloud Contract Verifier SetupGradle ProjectPrerequisitesIn order to use Spring Cloud Contract Verifier with WireMock you have to use Gradle or Maven plugin.If you want to use Spock in your projects you have to add separately
the spock-core and spock-spring modules. Check Spock docs for more informationAdd gradle plugin with dependenciesbuildscript {
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'
}Gradle and Rest Assured 2.0By default Rest Assured 3.x is added to the classpath. However in order to give the users the
opportunity to use Rest Assured 2.x it’s enough to add it to the plugins classpath.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 "com.jayway.restassured:rest-assured:2.5.0"
classpath "com.jayway.restassured:spring-mock-mvc:2.5.0"
}
}
depenendencies {
// all dependencies
// you can exclude rest-assured from spring-cloud-contract-verifier
testCompile "com.jayway.restassured:rest-assured:2.5.0"
testCompile "com.jayway.restassured:spring-mock-mvc:2.5.0"
}That way the plugin will automatically see that Rest Assured 2.x is present on the classpath
and will modify the imports accordingly.Snapshot versions for GradleAdd the additional snapshot repository to your build.gradle to use snapshot versions which are automatically uploaded after every successful build:buildscript {
repositories {
mavenCentral()
mavenLocal()
maven { url "http://repo.spring.io/snapshot" }
maven { url "http://repo.spring.io/milestone" }
maven { url "http://repo.spring.io/release" }
}
}Add stubsBy default Spring Cloud Contract Verifier is looking for stubs in src/test/resources/contracts 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 structuresrc/test/resources/contracts/myservice/shouldCreateUser.groovy
src/test/resources/contracts/myservice/shouldReturnUser.groovySpring Cloud Contract Verifier will create test class defaultBasePackage.MyService with two methodsshouldCreateUser()shouldReturnUser()Run pluginPlugin registers itself to be invoked before check 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 generateContractTests task.Default setupDefault Gradle Plugin setup creates the following Gradle part of the build (it’s a pseudocode)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
}
}
}Configure pluginTo change default configuration just add contracts snippet to your Gradle configcontracts {
testMode = 'MockMvc'
baseClassForTests = 'org.mycompany.tests'
generatedTestSourcesDir = project.file('src/generatedContract')
}Configuration optionstestMode - defines mode for acceptance tests. By default MockMvc which is based on Spring’s MockMvc. It can also be changed to JaxRsClient or to Explicit for real HTTP calls.imports - array with imports that should be included in generated tests (for example ['org.myorg.Matchers']). By default empty array []staticImports - array with static imports that should be included in generated tests(for example ['org.myorg.Matchers.*']). By default empty array []basePackageForTests - specifies base package for all generated tests. If not set the value will be picked from baseClassForTests’s package and from
`packageWithBaseClasses. If neither of these are set then the value will be set to org.springframework.cloud.contract.verifier.testsbaseClassForTests - base class for all generated tests. By default spock.lang.Specification if using Spock tests.packageWithBaseClasses - instead of providing a fixed value for base class you can provide a package where all the base classes lay. Takes precedence over baseClassForTests.baseClassMappings - explicitly map contract package to a FQN of a base class. Takes precedence over packageWithBaseClasses and baseClassForTests.ruleClassForTests - specifies Rule which should be added to generated test classes.ignoredFiles - Ant matcher allowing defining stub files for which processing should be skipped. By default empty array []contractsDslDir - directory containing contracts written using the GroovyDSL. By default $rootDir/src/test/resources/contractsgeneratedTestSourcesDir - test source directory where tests generated from Groovy DSL should be placed. By default $buildDir/generated-test-sources/contractVerifierstubsOutputDir - dir where the generated WireMock stubs from Groovy DSL should be placedtargetFramework - the target test framework to be used; currently Spock and JUnit are supported with JUnit being the default frameworkThe following properties are used when you want to provide where the JAR with contract layscontractDependency - the Dependency that provides groupid:artifactid:version:classifier coordinates. You can use the contractDependency closure to set it upcontractsPath - if contract deps are downloaded will default to groupid/artifactid where groupid will be slash separated. Otherwise will scan contracts under provided directorycontractsWorkOffline - in order not to download the dependencies each time you can download them once and work offline afterwards (reuse local Maven repo)Single base class for all testsWhen 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.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
}
}In case of using Explicit mode, you can use base class to initialize the whole tested app similarly as in regular integration tests. In case of JAXRSCLIENT mode this base class
should also contain protected WebTarget webTarget field, right now the only option to test JAX-RS API is to start a web server.Different base classes for contractsIf 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:follow a convention by providing the packageWithBaseClassesprovide explicit mapping via baseClassMappingsConventionThe convention is such that if you have a contract under e.g. src/test/resources/contract/foo/bar/baz/ and provide the value of the packageWithBaseClasses property
to com.example.base then we will assume that there is a BarBazBase class under com.example.base package. In other words we take last two parts of package
if they exist and form a class with a Base suffix. Takes precedence over baseClassForTests. Example of usage in the contracts closure:packageWithBaseClasses = 'com.example.base'MappingYou can manually map a regular expression of the contract’s package to fully qualified name of the base class for the matched contract.
Let’s take a look at the following example:baseClassForTests = "com.example.FooBase"
baseClassMappings {
baseClassMapping('.*/com/.*', 'com.example.ComBase')
baseClassMapping('.*/bar/.*':'com.example.BarBase')
}Let’s assume that you have contracts under
- src/test/resources/contract/com/
- src/test/resources/contract/foo/By providing the baseClassForTests we have a fallback in case mapping didn’t succeed (you could also provide
the packageWithBaseClasses as fallback). That way the tests generated from src/test/resources/contract/com/ contracts
will be extending the com.example.ComBase whereas the rest of tests will extend com.example.FooBase.Invoking generated testsTo ensure that provider side is complaint with defined contracts, you need to invoke:./gradlew generateContractTests testSpring Cloud Contract Verifier on consumer sideIn consumer service you need to configure Spring Cloud Contract Verifier plugin in exactly the same way as in case of provider. If you don’t want to use Stub Runner then you need to copy contracts stored in
src/test/resources/contracts and generate WireMock json stubs using:./gradlew generateClientStubsNote that stubsOutputDir option has to be set for stub generation to work.When present, json stubs can be used in consumer automated tests.@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
}
}Underneath LoanApplication makes a call to FraudDetection service. This request is handled by WireMock server configured using stubs generated by Spring Cloud Contract Verifier.Using in your Maven projectAdd maven pluginAdd the Spring Cloud Contract BOM<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud-dependencies.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>Next, the Spring Cloud Contract Verifier Maven plugin<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<packageWithBaseClasses>com.example.fraud</packageWithBaseClasses>
</configuration>
</plugin>You can read more in the Spring Cloud Contract Maven Plugin DocsMaven and Rest Assured 2.0By default Rest Assured 3.x is added to the classpath. However in order to give the users the
opportunity to use Rest Assured 2.x it’s enough to add it to the plugins classpath.<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<packageWithBaseClasses>com.example</packageWithBaseClasses>
</configuration>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-verifier</artifactId>
<version>${spring-cloud-contract.version}</version>
</dependency>
<dependency>
<groupId>com.jayway.restassured</groupId>
<artifactId>rest-assured</artifactId>
<version>2.5.0</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>com.jayway.restassured</groupId>
<artifactId>spring-mock-mvc</artifactId>
<version>2.5.0</version>
<scope>compile</scope>
</dependency>
</dependencies>
</plugin>
<dependencies>
<!-- all dependencies -->
<!-- you can exclude rest-assured from spring-cloud-contract-verifier -->
<dependency>
<groupId>com.jayway.restassured</groupId>
<artifactId>rest-assured</artifactId>
<version>2.5.0</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.jayway.restassured</groupId>
<artifactId>spring-mock-mvc</artifactId>
<version>2.5.0</version>
<scope>test</scope>
</dependency>
</dependencies>That way the plugin will automatically see that Rest Assured 3.x is present on the classpath
and will modify the imports accordingly.Snapshot versions for MavenFor Snapshot / Milestone versions you have to add the following section to your pom.xml<repositories>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
<repository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>Add stubsBy default Spring Cloud Contract Verifier is looking for stubs in src/test/resources/contracts 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 structuresrc/test/resources/contracts/myservice/shouldCreateUser.groovy
src/test/resources/contracts/myservice/shouldReturnUser.groovySpring Cloud Contract Verifier will create test class defaultBasePackage.MyService with two methods
- shouldCreateUser()
- shouldReturnUser()Run pluginPlugin goal generateTests is assigned to be invoked in phase generate-test-sources. 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 generateTests goal.Configure pluginTo change default configuration just add configuration section to plugin definition or execution definition.<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>convert</goal>
<goal>generateStubs</goal>
<goal>generateTests</goal>
</goals>
</execution>
</executions>
<configuration>
<basePackageForTests>org.springframework.cloud.verifier.twitter.place</basePackageForTests>
<baseClassForTests>org.springframework.cloud.verifier.twitter.place.BaseMockMvcSpec</baseClassForTests>
</configuration>
</plugin>Important configuration optionstestMode - defines mode for acceptance tests. By default MockMvc which is based on Spring’s MockMvc. It can also be changed to JaxRsClient or to Explicit for real HTTP calls.basePackageForTests - specifies base package for all generated tests. If not set the value will be picked from baseClassForTests’s package and from
`packageWithBaseClasses. If neither of these are set then the value will be set to org.springframework.cloud.contract.verifier.testsruleClassForTests - specifies Rule which should be added to generated test classes.baseClassForTests - base class for generated tests. By default spock.lang.Specification if using Spock tests.contractsDirectory - directory containing contracts written using the GroovyDSL. By default /src/test/resources/contracts.testFramework - the target test framework to be used; currently Spock and JUnit are supported with JUnit being the default frameworkpackageWithBaseClasses - 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 src/test/resources/contract/foo/bar/baz/ and provide the value of this property
to com.example.base then we will assume that there is a BarBazBase class under com.example.base package. Takes precedence
over baseClassForTestsbaseClassMappings - list of base class mappings that where you have to provide contractPackageRegex which is checked
against the package in which the contract lays and baseClassFQN that maps to fully qualified name of the base class for the matched
contract. If you have a contract under src/test/resources/contract/foo/bar/baz/ and map the property .* → com.example.base.BaseClass then
the test class generated from these contracts will extend com.example.base.BaseClass. Takes precedence over packageWithBaseClasses
and baseClassForTests.If you want to download your contract definitions from a Maven repository you can usecontractDependency - the contract dependency that contains all the packaged contractscontractsPath - path to concrete contracts in the JAR with packaged contracts. Defaults to groupid/artifactid where gropuid is slash separated.contractsWorkOffline - if the dependencies should be downloaded or local Maven only should be reusedcontractsRepositoryUrl - DEPRECATED PROPERTY - please use the contractRepository closure - URL to a repo with the artifacts with contracts, if not provided should use the current Maven onescontractRepository - closure where you can define properties related to repository with contractsusername - username to be used to connect to the repopassword - username to be used to connect to the repoproxyHost - proxy host to be used to connect to the repoproxyPort - proxy port to be used to connect to the repocacheDownloadedContracts - if you want to reuse download JARs that contain contract definitions.
We cache only non-snapshot, explicitly provided versions (e.g. + or 1.0.0.BUILD-SNAPSHOT won’t get cached).
By default this feature is turned on.Single base class for all testsWhen 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.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())
}
}In case of using Explicit mode, you can use base class to initialize the whole tested app similarly as in regular integration tests. In case of JAXRSCLIENT mode this base class should also contain protected WebTarget webTarget field, right now the only option to test JAX-RS API is to start a web server.Different base classes for contractsIf 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:follow a convention by providing the packageWithBaseClassesprovide explicit mapping via baseClassMappingsConventionThe convention is such that if you have a contract under e.g. src/test/resources/contract/hello/v1/ and provide the value of the packageWithBaseClasses property
to hello then we will assume that there is a HelloV1Base class under hello package. In other words we take last two parts of package
if they exist and form a class with a Base suffix. Takes precedence over baseClassForTests. Example of usage:<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<configuration>
<packageWithBaseClasses>hello</packageWithBaseClasses>
</configuration>
</plugin>MappingYou can manually map a regular expression of the contract’s package to fully qualified name of the base class for the matched contract.
You have to provide a list baseClassMappings of baseClassMapping that takes a contractPackageRegex to baseClassFQN mapping.
Let’s take a look at the following example:<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<configuration>
<baseClassForTests>com.example.FooBase</baseClassForTests>
<baseClassMappings>
<baseClassMapping>
<contractPackageRegex>.*com.*</contractPackageRegex>
<baseClassFQN>com.example.TestBase</baseClassFQN>
</baseClassMapping>
</baseClassMappings>
</configuration>
</plugin>Let’s assume that you have contracts under
- src/test/resources/contract/com/
- src/test/resources/contract/foo/By providing the baseClassForTests we have a fallback in case mapping didn’t succeed (you could also provide
the packageWithBaseClasses as fallback). That way the tests generated from src/test/resources/contract/com/ contracts
will be extending the com.example.ComBase whereas the rest of tests will extend com.example.FooBase.Invoking generated testsSpring Cloud Contract Maven Plugin generates verification code into directory /generated-test-sources/contractVerifier and attach this directory to testCompile goal.For Groovy Spock code use:<plugin>
<groupId>org.codehaus.gmavenplus</groupId>
<artifactId>gmavenplus-plugin</artifactId>
<version>1.5</version>
<executions>
<execution>
<goals>
<goal>testCompile</goal>
</goals>
</execution>
</executions>
<configuration>
<testSources>
<testSource>
<directory>${project.basedir}/src/test/groovy</directory>
<includes>
<include>**/*.groovy</include>
</includes>
</testSource>
<testSource>
<directory>${project.build.directory}/generated-test-sources/contractVerifier</directory>
<includes>
<include>**/*.groovy</include>
</includes>
</testSource>
</testSources>
</configuration>
</plugin>To ensure that provider side is complaint with defined contracts, you need to invoke mvn generateTest testFAQ with Maven PluginMaven Plugin and STSIn case you see the following exception while using STSSTS Exceptionwhen you click on the marker you should see sth like this 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) atIn order to fix this issue just provide the following section in your pom.xml<build>
<pluginManagement>
<plugins>
<!--This plugin's configuration is used to store Eclipse m2e settings
only. It has no influence on the Maven build itself. -->
<plugin>
<groupId>org.eclipse.m2e</groupId>
<artifactId>lifecycle-mapping</artifactId>
<version>1.0.0</version>
<configuration>
<lifecycleMappingMetadata>
<pluginExecutions>
<pluginExecution>
<pluginExecutionFilter>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<versionRange>[1.0,)</versionRange>
<goals>
<goal>convert</goal>
</goals>
</pluginExecutionFilter>
<action>
<execute />
</action>
</pluginExecution>
</pluginExecutions>
</lifecycleMappingMetadata>
</configuration>
</plugin>
</plugins>
</pluginManagement>
</build>Spring Cloud Contract Verifier on consumer sideYou 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
src/test/resources/contracts and generate WireMock json stubs using:
mvn generateStubs command. By default generated WireMock mapping is
stored in directory target/mappings. Your project should create from
this generated mappings additional artifact with classifier stubs for
easy deploy to maven repository.Sample configuration:<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${verifier-plugin.version}</version>
<executions>
<execution>
<goals>
<goal>convert</goal>
<goal>generateStubs</goal>
</goals>
</execution>
</executions>
</plugin>When present, json stubs can be used in consumer automated tests.@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();
}
}Underneath LoanApplication makes a call to the FraudDetection service. This request is handled by
a WireMock server configured using stubs generated by Spring Cloud Contract Verifier.ScenariosIt’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.my_contracts_dir\
scenario1\
1_login.groovy
2_showCart.groovy
3_logout.groovySuch tree will cause Spring Cloud Contract Verifier generating WireMock’s scenario with name scenario1 and three steps:login marked as Started pointing to:showCart marked as Step1 pointing to:logout marked as Step2 which will close the scenario.More details about WireMock scenarios can be found under http://wiremock.org/stateful-behaviour.htmlSpring Cloud Contract Verifier will also generate tests with guaranteed order of execution.Stubs and transitive dependenciesThe Maven and Gradle plugin that we’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:├── 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
├── ...
└── ...There are three possibilities of working with those dependencies so as not to have any issues with transitive dependencies.Mark all application dependencies as optionalIf in the github-webhook application we would mark all of our dependencies as optional, when you include the
github-webhook 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.Create a separate artifactid for stubsIf you create a separate artifactid then you can set it up in whatever way you wish. For example by having no dependencies at all.Exclude dependencies on the consumer sideAs a consumer, if you add the stub dependency to your classpath you can explicitly exclude the unwanted dependencies.Spring Cloud Contract Verifier MessagingSpring 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.IntegrationsYou can use one of the four integration configurations:Apache CamelSpring IntegrationSpring Cloud StreamSpring AMQPSince we’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.Remember to put @AutoConfigureMessageVerifier on the base class of your
generated tests. Otherwise messaging part of Spring Cloud Contract Verifier will not work.If you want to use Spring Cloud Stream remember to add a
org.springframework.cloud:spring-cloud-stream-test-support dependency.Maven<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream-test-support</artifactId>
<scope>test</scope>
</dependency>GradletestCompile "org.springframework.cloud:spring-cloud-stream-test-support"Manual Integration TestingThe main interface used by the tests is the org.springframework.cloud.contract.verifier.messaging.MessageVerifier.
It defines how to send and receive messages. You can create your own implementation to achieve the
same goal.In the a test you can inject a ContractVerifierMessageExchange to send and receive messages that follow the contract.
Then add @AutoConfigureMessageVerifier to your test, e.g.@RunWith(SpringTestRunner.class)
@SpringBootTest
@AutoConfigureMessageVerifier
public static class MessagingContractTests {
@Autowired
private MessageVerifier verifier;
...
}If your tests require stubs as well, then
@AutoConfigureStubRunner includes the messaging configuration, so
you only need the one annotation.Publisher side test generationHaving the input or outputMessage sections in your DSL will result in creation of tests on the publisher’s side. By default
JUnit tests will be created, however there is also a possibility to create Spock tests.There are 3 main scenarios that we should take into consideration: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)Scenario 2: the input message triggers an output messageScenario 3: the input message is consumed and there is no output messageThe destination passed to messageFrom or sentTo can have different meanings for different
messaging implementations. For Stream and Integration it’s first resolved as a destination of a channel, and then if
there is no such destination it’s resolved as a channel name. For Camel that’s a certain component (e.x. jms).Example for Camel:Scenario 1 (no input message)For the given contract:def contractDsl = Contract.make {
label 'some_label'
input {
triggeredBy('bookReturnedTriggered()')
}
outputMessage {
sentTo('activemq:output')
body('''{ "bookName" : "foo" }''')
headers {
header('BOOK-NAME', 'foo')
messagingContentType(applicationJson())
}
}
}The following JUnit test will be created:'''
// 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");
'''And the following Spock test would be created:'''
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")
'''Scenario 2 (output triggered by input)For the given contract: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')
}
}
}The following JUnit test will be created:'''
// 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");
'''And the following Spock test would be created:"""\
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")
"""Scenario 3 (no output message)For the given contract:def contractDsl = Contract.make {
label 'some_label'
input {
messageFrom('jms:delete')
messageBody([
bookName: 'foo'
])
messageHeaders {
header('sample', 'header')
}
assertThat('bookWasDeleted()')
}
}The following JUnit test will be created:'''
// given:
ContractVerifierMessage inputMessage = contractVerifierMessaging.create(
"{\\"bookName\\":\\"foo\\"}"
, headers()
.header("sample", "header"));
// when:
contractVerifierMessaging.send(inputMessage, "jms:delete");
// then:
bookWasDeleted();
'''And the following Spock test would be created:'''
given:
ContractVerifierMessage inputMessage = contractVerifierMessaging.create(
\'\'\'{"bookName":"foo"}\'\'\',
['sample': 'header']
)
when:
contractVerifierMessaging.send(inputMessage, 'jms:delete')
then:
noExceptionThrown()
bookWasDeleted()
'''Consumer Stub Side generationUnlike the HTTP part - in Messaging we need to publish the Groovy DSL inside the JAR with a stub. Then it’s parsed on the consumer side
and proper stubbed routes are created.For more information please consult the Stub Runner Messaging sections.Maven<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-stream-rabbit</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-contract-stub-runner</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream-test-support</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Edgware.BUILD-SNAPSHOT</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>Gradleext {
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
}
}
}Spring Cloud Contract Stub RunnerOne 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.Copying the JSON files / setting the client side for messaging manually is out of the question.That’s why we’ll introduce Spring Cloud Contract Stub Runner that can download and run the stubs
automatically for you.Snapshot versionsAdd the additional snapshot repository to your build.gradle to use snapshot versions which are automatically uploaded after every successful build:Maven<repositories>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
<repository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>https://repo.spring.io/release</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>Gradlebuildscript {
repositories {
mavenCentral()
mavenLocal()
maven { url "http://repo.spring.io/snapshot" }
maven { url "http://repo.spring.io/milestone" }
maven { url "http://repo.spring.io/release" }
}Publishing stubs as JARsThe easiest approach would be to centralize the way stubs are kept. For example you can keep them as JARs in a Maven repository.For both Maven and Gradle the setup comes out of the box. But you can customize it if you want to.Maven<!-- First disable the default jar setup in the properties section-->
<!-- we don't want the verifier to do a jar for us -->
<spring.cloud.contract.verifier.skip>true</spring.cloud.contract.verifier.skip>
<!-- Next add the assembly plugin to your build -->
<!-- we want the assembly plugin to generate the JAR -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<id>stub</id>
<phase>prepare-package</phase>
<goals>
<goal>single</goal>
</goals>
<inherited>false</inherited>
<configuration>
<attach>true</attach>
<descriptor>${basedir}/src/assembly/stub.xml</descriptor>
</configuration>
</execution>
</executions>
</plugin>
<!-- Finally setup your assembly. Below you can find the contents of src/main/assembly/stub.xml -->
<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 http://maven.apache.org/xsd/assembly-1.1.3.xsd">
<id>stubs</id>
<formats>
<format>jar</format>
</formats>
<includeBaseDirectory>false</includeBaseDirectory>
<fileSets>
<fileSet>
<directory>src/main/java</directory>
<outputDirectory>/</outputDirectory>
<includes>
<include>**com/example/model/*.*</include>
</includes>
</fileSet>
<fileSet>
<directory>${project.build.directory}/classes</directory>
<outputDirectory>/</outputDirectory>
<includes>
<include>**com/example/model/*.*</include>
</includes>
</fileSet>
<fileSet>
<directory>${project.build.directory}/snippets/stubs</directory>
<outputDirectory>META-INF/${project.groupId}/${project.artifactId}/${project.version}/mappings</outputDirectory>
<includes>
<include>**/*</include>
</includes>
</fileSet>
<fileSet>
<directory>${basedir}/src/test/resources/contracts</directory>
<outputDirectory>META-INF/${project.groupId}/${project.artifactId}/${project.version}/contracts</outputDirectory>
<includes>
<include>**/*.groovy</include>
</includes>
</fileSet>
</fileSets>
</assembly>Gradleext {
contractsDir = file("mappings")
stubsOutputDirRoot = file("${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
}
}
}Stub Runner CoreRuns stubs for service collaborators. Treating stubs as contracts of services allows to use stub-runner as an implementation of
Consumer Driven Contracts.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.Retrieving stubsYou can pick the following options of acquiring stubsAether based solution that downloads JARs with stubs from Artifactory / NexusClasspath scanning solution that searches classpath via pattern to retrieve stubsWrite your own implementation of the org.springframework.cloud.contract.stubrunner.StubDownloaderBuilder for full customizationThe latter example is described in the Custom Stub Runner section.Stub downloadingIf you provide the stubrunner.repositoryRoot or stubrunner.workOffline flag will be set
to true 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.Example:@AutoConfigureStubRunner(repositoryRoot="http://foo.bar", ids = "com.example:beer-api-producer:+:stubs:8095")Classpath scanningIf you DON’T provide the stubrunner.repositoryRoot and stubrunner.workOffline flag will
be set to false (that’s the default) then classpath will get scanned. Let’s look at the
following example:@AutoConfigureStubRunner(ids = {
"com.example:beer-api-producer:+:stubs:8095",
"com.example.foo:bar:1.0.0:superstubs:8096"
})If you’ve added the dependencies to your classpathMaven<dependency>
<groupId>com.example</groupId>
<artifactId>beer-api-producer-restdocs</artifactId>
<classifier>stubs</classifier>
<version>0.0.1-SNAPSHOT</version>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>*</groupId>
<artifactId>*</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>com.example.foo</groupId>
<artifactId>bar</artifactId>
<classifier>superstubs</classifier>
<version>1.0.0</version>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>*</groupId>
<artifactId>*</artifactId>
</exclusion>
</exclusions>
</dependency>GradletestCompile("com.example:beer-api-producer-restdocs:0.0.1-SNAPSHOT:stubs") {
transitive = false
}
testCompile("com.example.foo:bar:1.0.0:superstubs") {
transitive = false
}Then the following locations on your classpath will get scanned. For com.example:beer-api-producer-restdocs/META-INF/com.example/beer-api-producer-restdocs/*/.*/contracts/com.example/beer-api-producer-restdocs/*/.*/mappings/com.example/beer-api-producer-restdocs/*/.*and com.example.foo:bar/META-INF/com.example.foo/bar/*/.*/contracts/com.example.foo/bar/*/.*/mappings/com.example.foo/bar/*/.*As you can see you have to explicitly provide the group and artifact ids when packaging the
producer stubs.The producer would setup the contracts like this:└── src
└── test
└── resources
└── contracts
└── com.example
└── beer-api-producer-restdocs
└── nested
└── contract3.groovyTo achieve proper stub packaging.Or using the Maven assembly plugin or
Gradle Jar task you have to create the following
structure in your stubs jar.└── META-INF
└── com.example
└── beer-api-producer-restdocs
└── 2.0.0
├── contracts
│ └── nested
│ └── contract2.groovy
└── mappings
└── mapping.jsonBy maintaining this structure classpath gets scanned and you can profit from the messaging /
HTTP stubs without the need to download artifacts.Running stubsLimitationsThere 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 @DirtiesContext to shut down the stub servers, or else run them on
different ports per test.Running using main appYou can set the following options to the main class:-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 <Integer> Maximum port value to be assigned to
the WireMock instance. Defaults to
15000 (default: 15000)
--minPort, --minp <Integer> 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'HTTP StubsStubs are defined in JSON documents, whose syntax is defined in WireMock documentationExample:{
"request": {
"method": "GET",
"url": "/ping"
},
"response": {
"status": 200,
"body": "pong",
"headers": {
"Content-Type": "text/plain"
}
}
}Viewing registered mappingsEvery stubbed collaborator exposes list of defined mappings under __/admin/ endpoint.You can also use the mappingsOutputFolder property to dump the mappings to files.
For annotation based approach it would look like this@AutoConfigureStubRunner(ids="a.b.c:loanIssuance,a.b.c:fraudDetectionServer",
mappingsOutputFolder = "target/outputmappings/")and for the JUnit approach like this:@ClassRule @Shared StubRunnerRule rule = new StubRunnerRule()
.repoRoot("http://some_url")
.downloadStub("a.b.c", "loanIssuance")
.downloadStub("a.b.c:fraudDetectionServer")
.withMappingsOutputFolder("target/outputmappings")Then if you check out the folder target/outputmappings you would see the following structure.
├── fraudDetectionServer_13705
└── loanIssuance_12255That means that there were two stubs registered. fraudDetectionServer was registered at port 13705
and loanIssuance at port 12255. If we take a look at one of the files we would see (for WireMock)
mappings available for the given server:[{
"id" : "f9152eb9-bf77-4c38-8289-90be7d10d0d7",
"request" : {
"url" : "/name",
"method" : "GET"
},
"response" : {
"status" : 200,
"body" : "fraudDetectionServer"
},
"uuid" : "f9152eb9-bf77-4c38-8289-90be7d10d0d7"
},
...
]Messaging StubsDepending on the provided Stub Runner dependency and the DSL the messaging routes are automatically set up.Stub Runner JUnit RuleStub Runner comes with a JUnit rule thanks to which you can very easily download and run stubs for given group and artifact id:@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");After that rule gets executed Stub Runner connects to your Maven repository and for the given list of dependencies tries to:download themcache them locallyunzip them to a temporary folderstart a WireMock server for each Maven dependency on a random port from the provided range of ports / provided portfeed the WireMock server with all JSON files that are valid WireMock definitionscan also send messages (remember to pass an implementation of MessageVerifier interface)Stub Runner uses Eclipse Aether mechanism to download the Maven dependencies.
Check their docs for more information.Since the StubRunnerRule implements the StubFinder it allows you to find the started stubs: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<StubConfiguration, Collection<Contract>> getContracts();
}Example of usage in Spock tests:@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")
.withMappingsOutputFolder("target/outputmappingsforrule")
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'
}
def 'should output mappings to output folder'() {
when:
def url = rule.findStubUrl('fraudDetectionServer')
then:
new File("target/outputmappingsforrule", "fraudDetectionServer_${url.port}").exists()
}Example of usage in JUnit tests:@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");
}Check the Common properties for JUnit and Spring for more information on how to apply global configuration of Stub Runner.To use the JUnit rule together with messaging you have to provide an implementation of the
MessageVerifier interface to the rule builder (e.g. rule.messageVerifier(new MyMessageVerifier())).
If you don’t do this then whenever you try to send a message an exception will be thrown.Maven settingsThe 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.Providing fixed portsYou 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.Fluent APIWhen using the StubRunnerRule you can add a stub to download and then pass the port for the last downloaded stub.@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");You can see that for this example the following test is valid:then(rule.findStubUrl("loanIssuance")).isEqualTo(URI.create("http://localhost:12345").toURL());
then(rule.findStubUrl("fraudDetectionServer")).isEqualTo(URI.create("http://localhost:12346").toURL());Stub Runner with SpringSets up Spring configuration of the Stub Runner project.By providing a list of stubs inside your configuration file the Stub Runner automatically downloads
and registers in WireMock the selected stubs.If you want to find the URL of your stubbed dependency you can autowire the StubFinder interface and use
its methods as presented below:@ContextConfiguration(classes = Config, loader = SpringBootContextLoader)
@SpringBootTest(properties = [" stubrunner.cloud.enabled=false",
"stubrunner.camel.enabled=false",
'foo=${stubrunner.runningstubs.fraudDetectionServer.port}'])
@AutoConfigureStubRunner(mappingsOutputFolder = "target/outputmappings/")
@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'
"${stubFinder.findStubUrl('fraudDetectionServer').toString()}/name".toURL().text == 'fraudDetectionServer'
}
def 'should throw an exception when stub is not found'() {
when:
stubFinder.findStubUrl('nonExistingService')
then:
thrown(StubNotFoundException)
when:
stubFinder.findStubUrl('nonExistingGroupId', 'nonExistingArtifactId')
then:
thrown(StubNotFoundException)
}
def 'should register started servers as environment variables'() {
expect:
environment.getProperty("stubrunner.runningstubs.loanIssuance.port") != null
stubFinder.findAllRunningStubs().getPort("loanIssuance") == (environment.getProperty("stubrunner.runningstubs.loanIssuance.port") as Integer)
and:
environment.getProperty("stubrunner.runningstubs.fraudDetectionServer.port") != null
stubFinder.findAllRunningStubs().getPort("fraudDetectionServer") == (environment.getProperty("stubrunner.runningstubs.fraudDetectionServer.port") as Integer)
}
def 'should be able to interpolate a running stub in the passed test property'() {
given:
int fraudPort = stubFinder.findAllRunningStubs().getPort("fraudDetectionServer")
expect:
fraudPort > 0
environment.getProperty("foo", Integer) == fraudPort
foo == fraudPort
}
def 'should dump all mappings to a file'() {
when:
def url = stubFinder.findStubUrl("fraudDetectionServer")
then:
new File("target/outputmappings/", "fraudDetectionServer_${url.port}").exists()
}
@Configuration
@EnableAutoConfiguration
static class Config {}
}for the following configuration file: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
cloud:
enabled: false
camel:
enabled: false
spring.cloud:
consul.enabled: false
service-registry.enabled: falseInstead of using the properties you can also use the properties inside the @AutoConfigureStubRunner.
Below you can find an example of achieving the same result by setting values on the annotation.@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/")Stub Runner Spring registers environment variables in the following manner
for every registered WireMock server. Example for Stub Runner ids
com.example:foo, com.example:bar.stubrunner.runningstubs.foo.portstubrunner.runningstubs.bar.portWhich you can reference in your code.Stub Runner Spring CloudStub Runner can integrate with Spring Cloud.For real life examples you can check theproducer app sampleconsumer app sampleStubbing Service DiscoveryThe most important feature of Stub Runner Spring Cloud is the fact that it’s stubbingDiscoveryClientRibbonServerListthat means that regardless of the fact whether you’re using Zookeeper, Consul, Eureka or anything else, you don’t need that in your tests.
We’re starting WireMock instances of your dependencies and we’re telling your application whenever you’re using Feign, load balanced RestTemplate
or DiscoveryClient directly, to call those stubbed servers instead of calling the real Service Discovery tool.For example this test will passdef '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'
}for the following configuration filespring.cloud:
zookeeper.enabled: false
consul.enabled: false
eureka.client.enabled: false
stubrunner:
camel.enabled: false
idsToServiceIds:
ivyNotation: someValueInsideYourCode
fraudDetectionServer: someNameThatShouldMapFraudDetectionServerTest profiles and service discoveryIn your integration tests you typically don’t want to call neither a discovery service (e.g. Eureka)
or Config Server. That’s why you create an additional test configuration in which you want to disable
these features.Due to certain limitations of spring-cloud-commons to achieve this you have disable these properties
via a static block like presented below (example for Eureka) //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");
}Additional ConfigurationYou can match the artifactId of the stub with the name of your app by using the stubrunner.idsToServiceIds: map.
You can disable Stub Runner Ribbon support by providing: stubrunner.cloud.ribbon.enabled equal to false
You can disable Stub Runner support by providing: stubrunner.cloud.enabled equal to falseBy default all service discovery will be stubbed. That means that regardless of the fact if you have
an existing DiscoveryClient its results will be ignored. However, if you want to reuse it, just set
stubrunner.cloud.delegate.enabled to true and then your existing DiscoveryClient results will be
merged with the stubbed ones.Stub Runner Boot ApplicationSpring 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.One of the use-cases is to run some smoke (end to end) tests on a deployed application.
You can check out the Spring Cloud Pipelines
project for more information.How to use it?Stub Runner ServerJust add thecompile "org.springframework.cloud:spring-cloud-starter-stub-runner"Annotate a class with @EnableStubRunnerServer, build a fat-jar and you’re ready to go!For the properties check the Stub Runner Spring section.Spring Cloud CLIStarting from 1.4.0.RELEASE version of the Spring Cloud CLI
project you can start Stub Runner Boot by executing spring cloud stubrunner.In order to pass the configuration just create a stubrunner.yml file in the current working directory
or a subdirectory called config or in ~/.spring-cloud. The file could look like this
(example for running stubs installed locally)stubrunner.ymlstubrunner:
workOffline: true
ids:
- com.example:beer-api-producer:+:9876and then just call spring cloud stubrunner from your terminal window to start
the Stub Runner server. It will be available at port 8750.EndpointsHTTPGET /stubs - returns a list of all running stubs in ivy:integer notationGET /stubs/{ivy} - returns a port for the given ivy notation (when calling the endpoint ivy can also be artifactId only)MessagingFor MessagingGET /triggers - returns a list of all running labels in ivy : [ label1, label2 …] notationPOST /triggers/{label} - executes a trigger with labelPOST /triggers/{ivy}/{label} - executes a trigger with label for the given ivy notation (when calling the endpoint ivy can also be artifactId only)Example@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/${stubId}")
then:
response.statusCode == 200
response.body.as(Integer) > 0
where:
stubId << ['org.springframework.cloud.contract.verifier.stubs:bootService:+:stubs',
'org.springframework.cloud.contract.verifier.stubs:bootService:0.0.1-SNAPSHOT:stubs',
'org.springframework.cloud.contract.verifier.stubs:bootService:+',
'org.springframework.cloud.contract.verifier.stubs:bootService',
'bootService']
}
def 'should return 404 when missing stub was called'() {
when:
def response = RestAssuredMockMvc.get("/stubs/a:b:c:d")
then:
response.statusCode == 404
}
def 'should return a list of messaging labels that can be triggered when version and classifier are passed'() {
when:
String response = RestAssuredMockMvc.get('/triggers').body.asString()
then:
def root = new JsonSlurper().parseText(response)
root.'org.springframework.cloud.contract.verifier.stubs:bootService:0.0.1-SNAPSHOT:stubs'?.containsAll(["delete_book","return_book_1","return_book_2"])
}
def 'should trigger a messaging label'() {
given:
StubRunning stubRunning = Mock()
RestAssuredMockMvc.standaloneSetup(new HttpStubsController(stubRunning), new TriggerController(stubRunning))
when:
def response = RestAssuredMockMvc.post("/triggers/delete_book")
then:
response.statusCode == 200
and:
1 * stubRunning.trigger('delete_book')
}
def 'should trigger a messaging label for a stub with [#stubId] ivy notation'() {
given:
StubRunning stubRunning = Mock()
RestAssuredMockMvc.standaloneSetup(new HttpStubsController(stubRunning), new TriggerController(stubRunning))
when:
def response = RestAssuredMockMvc.post("/triggers/$stubId/delete_book")
then:
response.statusCode == 200
and:
1 * stubRunning.trigger(stubId, 'delete_book')
where:
stubId << ['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=")
}
}Stub Runner Boot with Service DiscoveryOne 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’s assume that you don’t want to deploy 50 microservice to a test environment in order
to check if your application is working fine. You’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’s working fine. We can call those tests smoke-tests since their idea is to check only a handful
of testing scenarios.The problem with this approach is such that if you’re doing microservices most likely you’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’s take a look at an example of
such a setup with Eureka. Let’s assume that Eureka was already running.@SpringBootApplication
@EnableStubRunnerServer
@EnableEurekaClient
@AutoConfigureStubRunner
public class StubRunnerBootEurekaExample {
public static void main(String[] args) {
SpringApplication.run(StubRunnerBootEurekaExample.class, args);
}
}As you can see we want to start a Stub Runner Boot server @EnableStubRunnerServer, enable Eureka client @EnableEurekaClient
and we want to have the stub runner feature turned on @AutoConfigureStubRunner.Now let’s assume that we want to start this application so that the stubs get automatically registered.
We can do it by running the app java -jar ${SYSTEM_PROPS} stub-runner-boot-eureka-example.jar where
${SYSTEM_PROPS} would contain the following list of properties-Dstubrunner.repositoryRoot=http://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 mappingThat 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 application.yml 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.Stubs Per ConsumerThere are cases in which 2 consumers of the same endpoint want to have 2 different responses.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.Let’s look at the following example for contract defined for the producer called producer.
There are 2 consumers: foo-consumer and bar-consumer.Consumer foo-servicerequest {
url '/foo'
method GET()
}
response {
status 200
body(
foo: "foo"
}
}Consumer bar-servicerequest {
url '/foo'
method GET()
}
response {
status 200
body(
bar: "bar"
}
}You can’t produce for the same request 2 different responses. That’s why you can properly package the
contracts and then profit from the stubsPerConsumer feature.On the producer side the consumers can have a folder that contains contracts related only to them.
By setting the stubrunner.stubs-per-consumer flag to true we no longer register all stubs but only those that
correspond to the consumer application’s name. In other words we’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.On the foo producer side the contracts would look like this.
└── contracts
├── bar-consumer
│ ├── bookReturnedForBar.groovy
│ └── shouldCallBar.groovy
└── foo-consumer
├── bookReturnedForFoo.groovy
└── shouldCallFoo.groovyBeing the bar-consumer consumer you can either set the spring.application.name or the stubrunner.consumer-name to bar-consumer
Or set the test as follows:@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 {
...
}Then only the stubs registered under a path that contains the bar-consumer in its name (i.e. those from the
src/test/resources/contracts/bar-consumer/some/contracts/… folder) will be allowed to be referenced.Or set the consumer name explicitly@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 {
...
}Then only the stubs registered under a path that contains the foo-consumer in its name (i.e. those from the
src/test/resources/contracts/foo-consumer/some/contracts/… folder) will be allowed to be referenced.You can check out issue 224 for more
information about the reasons behind this change.CommonCommon properties for JUnit and SpringSome 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:Property nameDefault valueDescriptionstubrunner.minPort10000Minimal value of a port for a started WireMock with stubsstubrunner.maxPort15000Minimal value of a port for a started WireMock with stubsstubrunner.repositoryRootMaven repo url. If blank then will call the local maven repostubrunner.classifierstubsDefault classifier for the stub artifactsstubrunner.workOfflinefalseIf true then will not contact any remote repositories to download stubsstubrunner.idsArray of Ivy notation stubs to downloadstubrunner.usernameOptional username to access the tool that stores the JARs with stubsstubrunner.passwordOptional password to access the tool that stores the JARs with stubsstubrunner.stubsPerConsumerfalseSet to true if you want to use different stubs per each consumer instead of registering all stubs for every consumerstubrunner.consumerNameIf you want to use stubs per consumer and want to override the consumer name just change this valueStub runner stubs idsYou can provide the stubs to download via the stubrunner.ids system property. They follow the following pattern:groupId:artifactId:version:classifier:portversion, classifier and port are optional.If you don’t provide the port then a random one will be pickedIf you don’t provide the classifier then the default one will be taken. (NOTE that you can pass an empty classifier like this groupId:artifactId:version:)If you don’t provide the version then the + will be passed and the latest one will be downloadedWhere port means the port of the WireMock server.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 Aether versioning ranges here.Taken from Aether Docs:
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.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" < "beta" = "b" < "milestone" = "m" < "cr" = "rc" < "snapshot" < "final" = "ga" < "sp". All of those well-known qualifiers
are considered smaller/older than other strings. An empty segment/string is equivalent to 0.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]".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" < "1.0.1-ga" = "1.0.1".
Stub Runner for MessagingStub Runner has the functionality to run the published stubs in memory. It can integrate with the following frameworks out of the boxSpring IntegrationSpring Cloud StreamApache CamelSpring AMQPIt also provides points of entry to integrate with any other solution on the market.If you have multiple frameworks on the classpath Stub Runner will need to
define which one should be used. Let’s assume that you have both AMQP, Spring Cloud Stream and Spring Integration
on the classpath. Then you need to set stubrunner.stream.enabled=false and stubrunner.integration.enabled=false.
That way the only remaining framework is Spring AMQP.Stub triggeringTo trigger a message it’s enough to use the StubTrigger interface: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<String, Collection<String>> labels();
}For convenience the StubFinder interface extends StubTrigger so it’s enough to use only one in your tests.StubTrigger gives you the following options to trigger a message:Trigger by labelstubFinder.trigger('return_book_1')Trigger by group and artifact idsstubFinder.trigger('org.springframework.cloud.contract.verifier.stubs:camelService', 'return_book_1')Trigger by artifact idsstubFinder.trigger('camelService', 'return_book_1')Trigger all messagesstubFinder.trigger()Stub Runner CamelSpring Cloud Contract Verifier Stub Runner’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.Adding it to the projectIt’s enough to have both Apache Camel and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with @AutoConfigureStubRunner.Disabling the functionalityIf you need to disable this functionality just pass stubrunner.camel.enabled=false property.ExamplesStubs structureLet us assume that we have the following Maven repository with a deployed stubs for the
camelService application.└── .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.xmlAnd the stubs contain the following structure:├── META-INF
│ └── MANIFEST.MF
└── repository
├── accurest
│ ├── bookDeleted.groovy
│ ├── bookReturned1.groovy
│ └── bookReturned2.groovy
└── mappingsLet’s consider the following contracts (let' number it with 1):Contract.make {
label 'return_book_1'
input {
triggeredBy('bookReturnedTriggered()')
}
outputMessage {
sentTo('jms:output')
body('''{ "bookName" : "foo" }''')
headers {
header('BOOK-NAME', 'foo')
}
}
}and number 2Contract.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')
}
}
}Scenario 1 (no input message)So as to trigger a message via the return_book_1 label we’ll use the StubTigger interface as followsstubFinder.trigger('return_book_1')Next we’ll want to listen to the output of the message sent to jms:outputExchange receivedMessage = camelContext.createConsumerTemplate().receive('jms:output', 5000)And the received message would pass the following assertionsreceivedMessage != null
assertThatBodyContainsBookNameFoo(receivedMessage.in.body)
receivedMessage.in.headers.get('BOOK-NAME') == 'foo'Scenario 2 (output triggered by input)Since the route is set for you it’s enough to just send a message to the jms:output destination.camelContext.createProducerTemplate().sendBodyAndHeaders('jms:input', new BookReturned('foo'), [sample: 'header'])Next we’ll want to listen to the output of the message sent to jms:outputExchange receivedMessage = camelContext.createConsumerTemplate().receive('jms:output', 5000)And the received message would pass the following assertionsreceivedMessage != null
assertThatBodyContainsBookNameFoo(receivedMessage.in.body)
receivedMessage.in.headers.get('BOOK-NAME') == 'foo'Scenario 3 (input with no output)Since the route is set for you it’s enough to just send a message to the jms:output destination.camelContext.createProducerTemplate().sendBodyAndHeaders('jms:delete', new BookReturned('foo'), [sample: 'header'])Stub Runner IntegrationSpring Cloud Contract Verifier Stub Runner’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.Adding it to the projectIt’s enough to have both Spring Integration and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with @AutoConfigureStubRunner.Disabling the functionalityIf you need to disable this functionality just pass stubrunner.integration.enabled=false property.ExamplesStubs structureLet us assume that we have the following Maven repository with a deployed stubs for the
integrationService application.└── .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.xmlAnd the stubs contain the following structure:├── META-INF
│ └── MANIFEST.MF
└── repository
├── accurest
│ ├── bookDeleted.groovy
│ ├── bookReturned1.groovy
│ └── bookReturned2.groovy
└── mappingsLet’s consider the following contracts (let' number it with 1):Contract.make {
label 'return_book_1'
input {
triggeredBy('bookReturnedTriggered()')
}
outputMessage {
sentTo('output')
body('''{ "bookName" : "foo" }''')
headers {
header('BOOK-NAME', 'foo')
}
}
}and number 2Contract.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')
}
}
}and the following Spring Integration Route:<?xml version="1.0" encoding="UTF-8"?>
<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
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/integration
http://www.springframework.org/schema/integration/spring-integration.xsd">
<!-- REQUIRED FOR TESTING -->
<bridge input-channel="output"
output-channel="outputTest"/>
<channel id="outputTest">
<queue/>
</channel>
</beans:beans>Scenario 1 (no input message)So as to trigger a message via the return_book_1 label we’ll use the StubTigger interface as followsstubFinder.trigger('return_book_1')Next we’ll want to listen to the output of the message sent to outputMessage<?> receivedMessage = messaging.receive('outputTest')And the received message would pass the following assertionsreceivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'Scenario 2 (output triggered by input)Since the route is set for you it’s enough to just send a message to the output destination.messaging.send(new BookReturned('foo'), [sample: 'header'], 'input')Next we’ll want to listen to the output of the message sent to outputMessage<?> receivedMessage = messaging.receive('outputTest')And the received message would pass the following assertionsreceivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'Scenario 3 (input with no output)Since the route is set for you it’s enough to just send a message to the input destination.messaging.send(new BookReturned('foo'), [sample: 'header'], 'delete')Stub Runner StreamSpring Cloud Contract Verifier Stub Runner’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.In Stub Runner’s integration with Stream the messageFrom or sentTo Strings are resolved
first as a destination of a channel, and then if there is no such destination it’s resolved as a
channel name.If you want to use Spring Cloud Stream remember to add a
org.springframework.cloud:spring-cloud-stream-test-support dependency.Maven<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream-test-support</artifactId>
<scope>test</scope>
</dependency>GradletestCompile "org.springframework.cloud:spring-cloud-stream-test-support"Adding it to the projectIt’s enough to have both Spring Cloud Stream and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with @AutoConfigureStubRunner.Disabling the functionalityIf you need to disable this functionality just pass stubrunner.stream.enabled=false property.ExamplesStubs structureLet us assume that we have the following Maven repository with a deployed stubs for the
streamService application.└── .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.xmlAnd the stubs contain the following structure:├── META-INF
│ └── MANIFEST.MF
└── repository
├── accurest
│ ├── bookDeleted.groovy
│ ├── bookReturned1.groovy
│ └── bookReturned2.groovy
└── mappingsLet’s consider the following contracts (let' number it with 1):Contract.make {
label 'return_book_1'
input { triggeredBy('bookReturnedTriggered()') }
outputMessage {
sentTo('returnBook')
body('''{ "bookName" : "foo" }''')
headers { header('BOOK-NAME', 'foo') }
}
}and number 2Contract.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') }
}
}and the following Spring configuration: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: trueScenario 1 (no input message)So as to trigger a message via the return_book_1 label we’ll use the StubTrigger interface as followsstubFinder.trigger('return_book_1')Next we’ll want to listen to the output of the message sent to a channel whose destination is returnBookMessage<?> receivedMessage = messaging.receive('returnBook')And the received message would pass the following assertionsreceivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'Scenario 2 (output triggered by input)Since the route is set for you it’s enough to just send a message to the bookStoragedestination.messaging.send(new BookReturned('foo'), [sample: 'header'], 'bookStorage')Next we’ll want to listen to the output of the message sent to returnBookMessage<?> receivedMessage = messaging.receive('returnBook')And the received message would pass the following assertionsreceivedMessage != null
assertJsons(receivedMessage.payload)
receivedMessage.headers.get('BOOK-NAME') == 'foo'Scenario 3 (input with no output)Since the route is set for you it’s enough to just send a message to the output destination.messaging.send(new BookReturned('foo'), [sample: 'header'], 'delete')Stub Runner Spring AMQPSpring Cloud Contract Verifier Stub Runner’s messaging module provides an easy way to integrate with Spring AMQP’s Rabbit Template.
For the provided artifacts it will automatically download the stubs and register the required
routes.The integration tries to work standalone, that is without interaction with a running RabbitMQ message broker.
It expects a RabbitTemplate on the application context and uses it as a spring boot test @SpyBean.
Thus it can use the mockito spy functionality to verify and introspect messages sent by the application.On the message consumer side, it considers all @RabbitListener annotated endpoints as well as all `SimpleMessageListenerContainer`s on the application context.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.Adding it to the projectIt’s enough to have both Spring AMQP and Spring Cloud Contract Stub Runner on the classpath and set the property stubrunner.amqp.enabled=true.
Remember to annotate your test class with @AutoConfigureStubRunner.If you already have Stream and Integration on the classpath you need
to disable them explicitly via stubrunner.stream.enabled=false and stubrunner.integration.enabled=false
propertiesExamplesStubs structureLet us assume that we have the following Maven repository with a deployed stubs for the
spring-cloud-contract-amqp-test application.└── .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.xmlAnd the stubs contain the following structure:├── META-INF
│ └── MANIFEST.MF
└── contracts
└── shouldProduceValidPersonData.groovyLet’s consider the following contract: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"
])
}
}and the following Spring configuration: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: 0Triggering the messageSo to trigger a message using the contract above we’ll use the StubTrigger interface as follows.stubTrigger.trigger("contract-test.person.created.event")The message has the destination contract-test.exchange so the Spring AMQP stub runner integration looks for bindings related to this exchange.@Bean
public Binding binding() {
return BindingBuilder.bind(new Queue("test.queue")).to(new DirectExchange("contract-test.exchange")).with("#");
}The binding definition binds the queue test.queue.
So the following listener definition is a match and is invoked with the contract message.@Bean
public SimpleMessageListenerContainer simpleMessageListenerContainer(ConnectionFactory connectionFactory,
MessageListenerAdapter listenerAdapter) {
SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
container.setConnectionFactory(connectionFactory);
container.setQueueNames("test.queue");
container.setMessageListener(listenerAdapter);
return container;
}Also, the following annotated listener represents a match and would be invoked.@RabbitListener(bindings = @QueueBinding(
value = @Queue(value = "test.queue"),
exchange = @Exchange(value = "contract-test.exchange", ignoreDeclarationExceptions = "true")))
public void handlePerson(Person person) {
this.person = person;
}The message is directly handed over to the onMessage method of the MessageListener associated with the matching SimpleMessageListenerContainer.Spring AMQP Test ConfigurationIn order to avoid that Spring AMQP is trying to connect to a running broker during our tests we configure a mock ConnectionFactory.To disable the mocked ConnectionFactory set the property stubrunner.amqp.mockConnection=falsestubrunner:
amqp:
mockConnection: falseContract DSLRemember that inside the contract file you have to provide the fully qualified name to
the Contract class and the make static import i.e. org.springframework.cloud.spec.Contract.make { … }.
You can also provide an import to the Contract class import org.springframework.cloud.spec.Contract and then call
Contract.make { … }Contract DSL is written in Groovy, but don’t be alarmed if you didn’t use Groovy before. Knowledge of the language is not really needed as our DSL uses only
a tiny subset of it (namely literals, method calls and closures). What’s more the DSL is designed to be programmer-readable without any knowledge of the DSL itself -
it’s statically typed.Spring Cloud Contract supports defining multiple contracts in a single file!The Contract is present in the spring-cloud-contract-spec module of the Spring Cloud Contract Verifier repository.Let’s look at full example of a contract definition.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": "http://api.twitter.com/1/geo/id/01fbe706f872cb32.json"
}
}]
'''
}
response {
status 200
}
}Not all features of the DSL are used in example above. If you didn’t find what you are looking for, please check next paragraphs on this page.
You can easily compile Contracts to WireMock stubs mapping using standalone maven command: mvn org.springframework.cloud:spring-cloud-contract-maven-plugin:convert.
LimitationsSpring Cloud Contract Verifier doesn’t support XML properly. Please use JSON or help us implement this feature.The support for the verification of size of JSON arrays is experimental. If you want to turn it on please provide
the value of a system property spring.cloud.contract.verifier.assert.size equal to true. By default this feature is set to
false. You can also provide the assertJsonSize property in the plugin configuration.Due to the fact that JSON structure can have any form it’s sometimes impossible to parse it properly when using
the value(consumer(…), producer(…)) notation when using that in GString. That’s why we highly recommend using the
Groovy Map notation.Common Top-Level elementsDescriptionYou can add a description to your contract that is nothing else but an arbitrary text. Example: org.springframework.cloud.contract.spec.Contract.make {
description('''
given:
An input
when:
Sth happens
then:
Output
''')
}NameYou can provide a name of your contract. Let’s assume that you’ve provided a name should register a user.
If you do this then the name of the autogenerated test will be equal to validate_should_register_a_user.
Also the name of the stub will be should_register_a_user.json in case of a WireMock stub.Please ensure that the name doesn’t contain any characters that will make the generated test
not possible to compile. Also remember that if you provide the same name for multiple contracts then your
autogenerated tests will fail to compile and your generated stubs will override each other.Ignoring contractsIf you want to ignore a contract you can either set a value of ignored contracts in the plugin configuration
or just set the ignored property on the contract itself:org.springframework.cloud.contract.spec.Contract.make {
ignored()
}Passing values from filesStarting with version 1.2.0 it’s possible to pass values from files. Let’s assume that we have
the following resources in our project.└── src
└── test
└── resources
└── contracts
├── readFromFile.groovy
├── request.json
└── response.jsonAnd our contract looks like this:import org.springframework.cloud.contract.spec.Contract
Contract.make {
request {
method('PUT')
headers {
contentType(applicationJson())
}
body(file("request.json"))
url("/1")
}
response {
status 200
body(file("response.json"))
headers {
contentType(textPlain())
}
}
}and the json files look like this:request.json{ "status" : "REQUEST" }response.json{ "status" : "RESPONSE" }When test / stub generation takes place then the contents of the file will be
passed to the body of request / response. All thanks to the file(…) method.
The argument of that method needs to be a file with location relative to the
folder in which the contract lays.HTTP Top-Level ElementsFollowing methods can be called in the top-level closure of a contract definition. Request and response are mandatory, priority is optional.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
}RequestHTTP protocol requires only method and address to be specified in a request. The same information is mandatory in request definition of the Contract.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 {
//...
}
}It is possible to specify whole url instead of just path, but urlPath is the recommended way as it makes the tests host-independent.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 {
//...
}
}Request may contain query parameters, which are specified in a closure nested in a call to urlPath or url.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 {
//...
}
}It may contain additional request headers…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 {
//...
}
}…and a request body.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 {
//...
}
}Request may contain multipart elements. Just call the multipart() method.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
}
}In this example we defined parameters either directly by using the map notation,
where the value can be a dynamic property (e.g. formParameter: $(consumer(…), producer(…)))
or by using the named(…) method that allows you to set a named parameter.
A named parameter can set a name and content. You can call it either via
a method with 2 arguments: e.g. named("fileName", "fileContent") or
via a map notation named(name: "fileName", content: "fileContent").From this contract the generated test will look more or less like this:// 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);The WireMock stub will look more or less like this: '''
{
"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" ]
}
}
'''ResponseMinimal response must contain HTTP status code.org.springframework.cloud.contract.spec.Contract.make {
request {
//...
}
response {
// Status code sent by the server
// in response to request specified above.
status 200
}
}Besides status response may contain headers and body, which are specified the same way as in the request (see previous paragraph).Dynamic propertiesThe contract can contain some dynamic properties - timestamps / ids etc. You don’t want to enforce the consumers to stub their
clocks to always return the same value of time so that it gets matched by the stub. That’s why we allow you to provide the dynamic
parts in your contracts in two ways. One is to pass them directly in the
body and one to set them in a separate section called testMatchers and stubMatchers.Dynamic properties inside the bodyYou can set the properties inside the body either via the value methodvalue(consumer(...), producer(...))
value(c(...), p(...))
value(stub(...), test(...))
value(client(...), server(...))or if you’re using the Groovy map notation for body you can use the $() method$(consumer(...), producer(...))
$(c(...), p(...))
$(stub(...), test(...))
$(client(...), server(...))All of the aforementioned approaches are equal. That means that stub and client methods are aliases over the consumer
method. Let’s take a closer look at what we can do with those values in the subsequent sections.Regular expressionsYou can use regular expressions to write your requests in Contract DSL. It 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 it when you need to use patterns and not exact values both
for your test and your server side tests.Please see the example below: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'
}
}
}You can also provide only one side of the communication using a regular expression. If you do that then automatically we’ll
provide the generated string that matches the provided regular expression. For example: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: $(producer(regex('[0-9]{7}')))
])
headers {
contentType("application/vnd.fraud.v1+json")
}
}
}In this example for request and response the opposite side of the communication will have the respective data generated.Spring Cloud Contract comes with a series of predefined regular expressions that you can use in your contracts.protected static final Pattern TRUE_OR_FALSE = Pattern.compile(/(true|false)/)
protected static final Pattern ONLY_ALPHA_UNICODE = Pattern.compile(/[\p{L}]*/)
protected static final Pattern NUMBER = Pattern.compile('-?\\d*(\\.\\d+)?')
protected static final Pattern IP_ADDRESS = Pattern.compile('([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.([01]?\\d\\d?|2[0-4]\\d|25[0-5])')
protected static final Pattern HOSTNAME_PATTERN = Pattern.compile('((http[s]?|ftp):/)/?([^:/\\s]+)(:[0-9]{1,5})?')
protected static final Pattern EMAIL = Pattern.compile('[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,6}')
protected static final Pattern URL = UrlHelper.URL
protected static final Pattern UUID = Pattern.compile('[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}')
protected static final Pattern ANY_DATE = Pattern.compile('(\\d\\d\\d\\d)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])')
protected static final Pattern ANY_DATE_TIME = Pattern.compile('([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])')
protected static final Pattern ANY_TIME = Pattern.compile('(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])')
protected static final Pattern NON_EMPTY = Pattern.compile(/[\S\s]+/)
protected static final Pattern NON_BLANK = Pattern.compile(/^\s*\S[\S\s]*/)
protected static final Pattern ISO8601_WITH_OFFSET = Pattern.compile(/([0-9]{4})-(1[0-2]|0[1-9])-(3[01]|0[1-9]|[12][0-9])T(2[0-3]|[01][0-9]):([0-5][0-9]):([0-5][0-9])(\.\d{3})?(Z|[+-][01]\d:[0-5]\d)/)
protected static Pattern anyOf(String... values){
return Pattern.compile(values.collect({"^$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()
}so in your contract you can use it like thisContract 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'))}]"
)
}
}Passing optional parametersIt is possible to provide optional parameters in your contract. It’s only possible to have optional parameter for the:STUB side of the RequestTEST side of the ResponseExample: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: $(consumer(regex(hostname())), producer('http://partners.com'))
)
}
response {
status 404
headers {
header 'Content-Type': 'application/json'
}
body(
code: value(consumer("123123"), producer(optional("123123")))
)
}
}By wrapping a part of the body with the optional() method you are in fact creating a regular expression that should be present 0 or more times.That way for the example above the following test would be generated if you pick Spock:"""
given:
def request = given()
.header("Content-Type", "application/json")
.body('''{"email":"abc@abc.com","callback_url":"http://partners.com"}''')
when:
def response = given().spec(request)
.post("/users/password")
then:
response.statusCode == 404
response.header('Content-Type') == 'application/json'
and:
DocumentContext parsedJson = JsonPath.parse(response.body.asString())
assertThatJson(parsedJson).field("['code']").matches("(123123)?")
"""and the following stub:'''
{
"request" : {
"url" : "/users/password",
"method" : "POST",
"bodyPatterns" : [ {
"matchesJsonPath" : "$[?(@.['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
}
'''Executing custom methods on server sideIt is also possible to define a method call to be executed on the server side during the test. Such a method can be added to the class defined as "baseClassForTests"
in the configuration. Example:Contractorg.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
}
}Base classabstract class BaseMockMvcSpec extends Specification {
def setup() {
RestAssuredMockMvc.standaloneSetup(new PairIdController())
}
void isProperCorrelationId(Integer correlationId) {
assert correlationId == 123456
}
void isEmpty(String value) {
assert value == null
}
}You can’t use both a String and execute to perform concatenation. E.g. calling
header('Authorization', 'Bearer ' + execute('authToken()')) will lead to improper results.
To make this work just call header('Authorization', execute('authToken()')) and ensure that
the authToken() method returns everything that you need.The type of the object read from the JSON can be one of the followings depending on the
JSON path:String if you point to a String value in a JSONJSONArray if you point to a List in a JSONMap if you point to a Map in a JSONproper Number if you point to Integer, Double etc. in a JSONBoolean if you point to a Boolean in a JSONIn the request part of the contract you can specify that the body should be
taken from a method.You have to provide both the consumer and the producer side
and the execute part can be applied for the whole body. Not for parts of it!Example:Contract contractDsl = Contract.make {
request {
method 'GET'
url '/something'
body(
$(c("foo"), p(execute("hashCode()")))
)
}
response {
status 200
}
}This will result in calling the hashCode() method in the request body.
It would more or less like this:// given:
MockMvcRequestSpecification request = given()
.body(hashCode());
// when:
ResponseOptions response = given().spec(request)
.get("/something");
// then:
assertThat(response.statusCode()).isEqualTo(200);Referencing request from responseThe best situation is to provide fixed values but sometimes you need to reference a request in your response.
In order to do this you can profit from the fromRequest() method that allows you to reference a bunch
of elements from the HTTP request. You can use the following options:fromRequest().url() - return the request URL and query parametersfromRequest().query(String key) - return the first query parameter with a given namefromRequest().query(String key, int index) - return the nth query parameter with a given namefromRequest().path() - return the full pathfromRequest().path(int index) - return the nth path elementfromRequest().header(String key) - return the first header with a given namefromRequest().header(String key, int index) - return the nth header with a given namefromRequest().body() - return the full request bodyfromRequest().body(String jsonPath) - return the element from the request that matches the JSON PathLet’s take a look at the following contractContract 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 ${fromRequest().header(authorization())} bar")
}
body(
url: fromRequest().url(),
path: fromRequest().path(),
pathIndex: fromRequest().path(1),
param: fromRequest().query("foo"),
paramIndex: fromRequest().query("foo", 1),
authorization: fromRequest().header("Authorization"),
authorization2: fromRequest().header("Authorization", 1),
fullBody: fromRequest().body(),
responseFoo: fromRequest().body('$.foo'),
responseBaz: fromRequest().body('$.baz'),
responseBaz2: "Bla bla ${fromRequest().body('$.foo')} bla bla"
)
}
}Running a JUnit test generation will lead in creation of a test looking more or less like this// 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&foo=bar2");
assertThatJson(parsedJson).field("['responseBaz2']").isEqualTo("Bla bla bar bla bla");As you can see elements from the request have been properly referenced in the response.The generated WireMock stub will look more or less like this:{
"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" ]
}
}So sending a request as the one presented in the request part of the contract will lead in sending the following
response body{
"url" : "/api/v1/xxxx?foo=bar&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"
}This feature will work only with WireMock having version greater or equal to 2.5.1. We’re using WireMock’s
response-template response transformer. It’s using Handlebars to convert the Mustache {{{ }}} templates into
proper values. Additionally we’re registering 2 helper functions. escapejsonbody - that escapes the request
body in a format that can be embedded in a JSON. Another is jsonpath that for a given parameter knows how to
find an object in the request body.Dynamic properties in matchers sectionsIf you’ve been working with Pact this might seem familiar. Quite a few users
are used to having a separation between the body and setting dynamic parts of your contract.That’s why you can profit from two separate sections. One is called stubMatchers where you can
define the dynamic values that should end up in a stub. You can set it in the request or inputMessage
part of your contract. The other is called testMatchers which is present in the response or
outputMessage side of the contract.Currently we support only JSON Path based matchers with the following matching possibilities.
For stubMatchers:byEquality() - the value taken from the response via the provided JSON Path needs
to be equal to the provided value in the contractbyRegex(…) - the value taken from the response via the provided JSON Path needs
to match the regexbyDate() - the value taken from the response via the provided JSON Path needs to
match the regex for ISO DatebyTimestamp() - the value taken from the response via the provided JSON Path needs
to match the regex for ISO DateTimebyTime() - the value taken from the response via the provided JSON Path needs to
match the regex for ISO TimeFor testMatchers:byEquality() - the value taken from the response via the provided JSON Path needs
to be equal to the provided value in the contractbyRegex(…) - the value taken from the response via the provided JSON Path needs
to match the regexbyDate() - the value taken from the response via the provided JSON Path needs to
match the regex for ISO DatebyTimestamp() - the value taken from the response via the provided JSON Path needs
to match the regex for ISO DateTimebyTime() - the value taken from the response via the provided JSON Path needs to
match the regex for ISO TimebyType() - 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.
byType can take a closure where you can set minOccurrence and maxOccurrence.
That way you can assert on the size of the flattened collection. To check the size
of an unflattened collection, use a custom method via byCommand(…) testMatcher.byCommand(…) - the value taken from the response via the provided JSON Path will be
passed as an input to the custom method that you’re providing. E.g. byCommand('foo($it)')
will result in calling a foo method to which the value matching the JSON Path will get
passed.The type of the object read from the JSON can be one of the followings depending on the
JSON path:String if you point to a String value in a JSONJSONArray if you point to a List in a JSONMap if you point to a Map in a JSONproper Number if you point to Integer, Double etc. in a JSONBoolean if you point to a Boolean in a JSONLet’s take a look at the following example: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 & 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())
}
}
}In this example we’re providing the dynamic portions of the contract in the matchers sections.
For the request part you can see that for all fields but valueWithoutAMatcher we’re setting
explicitly the values of regular expressions we’d like the stub to contain. For the valueWithoutAMatcher
the verification will take place in the same way as without the usage of matchers - the test
will perform an equality check in this case.For the response side in the testMatchers section we’re defining all the dynamic parts
in a similar manner. The only difference is that we have the byType matchers too. In that
case we’re checking 4 fields in the way that we’re verifying whether the response from the test
has a value whose JSON path matching the given field is of the same type as the one defined in the response body and:for $.valueWithTypeMatch - we’re just checking the whether the type is the samefor $.valueWithMin - we’re checking the type and assert if the size is greater or equal to the min occurrencefor $.valueWithMax - we’re checking the type and assert if the size is smaller or equal to the max occurrencefor $.valueWithMinMax - we’re checking the type and assert if the size is between the min and max occurrenceThe resulting test would look more or less like this (note that we’re separating the autogenerated
assertions and the one from matchers with an and section):// given:
MockMvcRequestSpecification request = given()
.header("Content-Type", "application/json")
.body("{\"duck\":123,\"alpha\":\"abc\",\"number\":123,\"aBoolean\":true,\"date\":\"2017-01-01\",\"dateTime\":\"2017-01-01T01:23:45\",\"time\":\"01:02:34\",\"valueWithoutAMatcher\":\"foo\",\"valueWithTypeMatch\":\"string\"}");
// when:
ResponseOptions response = given().spec(request)
.get("/get");
// then:
assertThat(response.statusCode()).isEqualTo(200);
assertThat(response.header("Content-Type")).matches("application/json.*");
// and:
DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
assertThatJson(parsedJson).field("valueWithoutAMatcher").isEqualTo("foo");
// and:
assertThat(parsedJson.read("$.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"));Notice that for the byCommand method we are calling the assertThatValueIsANumber. This method needs
to be defined in the test base class or should be statically imported to your tests.
Notice that the byCommand call was converted to assertThatValueIsANumber(parsedJson.read("$.duck"));. That means
that we took the method name and passed the proper JSON path as a parameter to it.and the WireMock stub like this: '''
{
"request" : {
"urlPath" : "/get",
"method" : "POST",
"headers" : {
"Content-Type" : {
"matches" : "application/json.*"
}
},
"bodyPatterns" : [ {
"matchesJsonPath" : "$[?(@.['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" : "{\\"date\\":\\"2017-01-01\\",\\"dateTime\\":\\"2017-01-01T01:23:45\\",\\"number\\":123,\\"aBoolean\\":true,\\"duck\\":123,\\"alpha\\":\\"abc\\",\\"valueWithMin\\":[1,2,3],\\"time\\":\\"01:02:34\\",\\"valueWithTypeMatch\\":\\"string\\",\\"valueWithMax\\":[1,2,3],\\"valueWithMinMax\\":[1,2,3],\\"valueWithoutAMatcher\\":\\"foo\\"}",
"headers" : {
"Content-Type" : "application/json"
}
}
}
'''If you use a matcher then the part of the request / response that the matcher is addressing
via the JSON Path will get removed from assertion. In case of verifying a collection you have to create
matchers for all elements of the collection.Let’s look at the following example: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('.+'))
}
}
}This will lead in creating the following test (showing just the assertion section)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(".+")As you can see the assertion is malformed. That’s because only the first element of the array got asserted.
In order to fix this it’s best to apply the assertion to the whole $.events collection and assert it
via the byCommand(…) method.JAX-RS supportWe support JAX-RS 2 Client API. Base class needs to define protected WebTarget webTarget and server initialization, right now the only option how to test JAX-RS API is to start a web server.Request with a body needs to have a content type set otherwise application/octet-stream is going to be used.In order to use JAX-RS mode, use the following settings:testMode == 'JAXRSCLIENT'Example of a test API generated:'''
// when:
Response response = webTarget
.path("/users")
.queryParam("limit", "10")
.queryParam("offset", "20")
.queryParam("filter", "email")
.queryParam("sort", "name")
.queryParam("search", "55")
.queryParam("age", "99")
.queryParam("name", "Denis.Stepanov")
.queryParam("email", "bob@email.com")
.request()
.method("GET");
String responseAsString = response.readEntity(String.class);
// then:
assertThat(response.getStatus()).isEqualTo(200);
// and:
DocumentContext parsedJson = JsonPath.parse(responseAsString);
assertThatJson(parsedJson).field("['property1']").isEqualTo("a");
'''Async supportIf you’re using asynchronous communication on the server side (your controllers are returning
Callable, DeferredResult etc. then inside your contract you have to provide in the response
section a async() method. Example:org.springframework.cloud.contract.spec.Contract.make {
request {
method GET()
url '/get'
}
response {
status 200
body 'Passed'
async()
}
}Working with Context PathsSpring Cloud Contract supports context paths.The only thing that changes in order to fully support context paths is the switch
on the PRODUCER side. The autogenerated tests need to be using the EXPLICIT mode.The consumer side remains untouched, in order for the generated test to pass you have to switch the EXPLICIT mode.Maven<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<testMode>EXPLICIT</testMode>
</configuration>
</plugin>Gradlecontracts {
testMode = 'EXPLICIT'
}That way you’ll generate a test that DOES NOT use MockMvc. It means that you’re generating
real requests and you need to setup your generated test’s base class to work on a real socket.Let’s imagine the following contract:org.springframework.cloud.contract.spec.Contract.make {
request {
method 'GET'
url '/my-context-path/url'
}
response {
status 200
}
}Here is an example of how to set up a base class and Rest Assured for everything to work correctly.import io.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;
}
}That way all:all your requests in the autogenerated tests will be sent to the real endpoint with your context path included (e.g. /my-context-path/url)your contracts reflect that you have a context path, thus your generated stubs will also
have that information (e.g. in the stubs you’ll see that you have too call /my-context-path/url)Messaging Top-Level ElementsThe DSL for messaging looks a little bit different than the one that focuses on HTTP.Output triggered by a methodThe output message can be triggered by calling a method (e.g. a Scheduler was started and a message was sent)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')
}
}
}In this case the output message will be sent to output if a method called bookReturnedTriggered will be executed. In the message publisher’s side
we will generate a test that will call that method to trigger the message. On the consumer side you can use the some_label to trigger the message.Output triggered by a messageThe output message can be triggered by receiving a message.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')
}
}
}In this case the output message will be sent to output if a proper message will be received on the input destination. In the message publisher’s side
we will generate a test that will send the input message to the defined destination. On the consumer side you can either send a message to the input
destination or use the some_label to trigger the message.Consumer / ProducerIn HTTP you have a notion of client/stub and `server/test notation. You can use them also in messaging but we’re providing also the consumer and produer methods
as presented below (note you can use either $ or value methods to provide consumer and producer parts)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'
])
}
}Multiple contracts in one fileIt’s possible to define multiple contracts in one file. An example of such a contract can look like thisimport 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
}
}
]In this example one contract has the name field and the other doesn’t. This will lead to generation of
two tests that will look more or less like this: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);
}
}Notice that for the contract that has the name field the generated test method is named
validate_should_post_a_user. For the one that doesn’t have the name it’s called
validate_withList_1. It corresponds to the name of the file WithList.groovy and the
index of the contract in the list.The generated stubs will look like thisshould post a user.json
1_WithList.jsonAs you can see the first file got the name parameter from the contract. The second
got the name of the contract file WithList.groovy prefixed with the index (in this case
contract had index 1 in the list of contracts in the file).As you can see it’s much better if you name your contracts since then your tests
are far more meaningful.CustomizationExtending the DSLIt is possible to provide your own functions to the DSL. The key requirement for this
feature was to maintain the static compatibility. Below you will be able to see an example
of:creation of a JAR with reusable classesreferencing of these classes in the DSLsThe full example can be found here.Common JARBelow you can find three classes that we will reuse in the DSLs.PatternUtils contains functions used by both the consumer and the producer.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.
*
* <pre>
* {@code
* request {
* body(
* [ age: $(c(PatternUtils.oldEnough()))]
* )
* }
* </pre>
*
* 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[]ConsumerUtils contains functions used by the consumer.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
*
* <pre>
* {@code
* request {
* body(
* [ age: $(ConsumerUtils.oldEnough())]
* )
* }
* </pre>
*
* 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[]ProducerUtils contains functions used by the producer.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
*
* <pre>
* {@code
* response {
* body(
* [ status: $(ProducerUtils.ok())]
* )
* }
* </pre>
*
* That way it's in the implementation that we decide what value we will pass to the consumer
* and which one to the producer.
*/
public static ServerDslProperty ok() {
// this example is not the best one and
// theoretically you could just pass the regex instead of `ServerDslProperty` but
// it's just to show some new tricks :)
return new ServerDslProperty( PatternUtils.ok(), "OK");
}
}
//end::impl[]Adding the dependency to projectIn order for the plugins and IDE to be able to reference the common JAR classes you need
to pass the dependency to your project.Test dependency in project’s dependenciesFirst add the common jar dependency as a test dependency. That way since your
contracts files are available at test resources path, automatically the
common jar classes will be visible in your Groovy files.Maven<dependency>
<groupId>com.example</groupId>
<artifactId>beer-common</artifactId>
<version>${project.version}</version>
<scope>test</scope>
</dependency>GradletestCompile("com.example:beer-common:0.0.1-SNAPSHOT")Test dependency in plugin’s dependenciesNow you have to add the dependency for the plugin to reuse at runtime.Maven<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<packageWithBaseClasses>com.example</packageWithBaseClasses>
<baseClassMappings>
<baseClassMapping>
<contractPackageRegex>.*intoxication.*</contractPackageRegex>
<baseClassFQN>com.example.intoxication.BeerIntoxicationBase</baseClassFQN>
</baseClassMapping>
</baseClassMappings>
</configuration>
<dependencies>
<dependency>
<groupId>com.example</groupId>
<artifactId>beer-common</artifactId>
<version>${project.version}</version>
<scope>compile</scope>
</dependency>
</dependencies>
</plugin>Gradleclasspath "com.example:beer-common:0.0.1-SNAPSHOT"Referencing classes in DSLsNow you can reference your classes in your DSL. Example: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())
}
}
}Pluggable architectureThere are cases where you have your contracts defined in other formats
like YAML, RAML or PACT. On the other hand you’d like to profit from
the test and stubs generation. It’s really easy to add your own implementation
of either of those. Also you can customize the way tests are generated (for example you can generate
tests for other languages) and you can do the same for stubs generation (you can generate
stubs for other stub http server implementations).Custom contract converterLet’s assume that your contract is written in a YAML file like this:request:
url: /foo
method: PUT
headers:
foo: bar
body:
foo: bar
response:
status: 200
headers:
foo2: bar
body:
foo2: barThanks to the interfacepackage 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 <T> - type to which we want to convert the contract
*
* @author Marcin Grzejszczak
* @since 1.1.0
*/
interface ContractConverter<T> {
/**
* 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<Contract> 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<Contract> contract)
}you can register your own implementation of a contract structure converter.
Your implementation needs to state the condition on which it should start the
conversion. Also you have to define how to perform that conversion in both ways.Once you create your implementation you have to create a /META-INF/spring.factories
file in which you provide the fully qualified name of your implementation.Example of a spring.factories file# Converters
org.springframework.cloud.contract.spec.ContractConverter=\
org.springframework.cloud.contract.verifier.converter.YamlContractConverterand the YAML implementationpackage 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<List<YamlContract>> {
@Override
public boolean isAccepted(File file) {
String name = file.getName()
return name.endsWith(".yml") || name.endsWith(".yaml")
}
@Override
public Collection<Contract> 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 ->
header(key, value)
}
}
body(yamlContract?.request?.body)
}
response {
status(yamlContract?.response?.status)
headers {
yamlContract?.response?.headers?.each { String key, Object value ->
header(key, value)
}
}
body(yamlContract?.response?.body)
}
}]
}
catch (FileNotFoundException e) {
throw new IllegalStateException(e)
}
}
@Override
public List<YamlContract> convertTo(Collection<Contract> contracts) {
return contracts.collect { Contract contract ->
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
}
}
}Pact converterSpring Cloud Contract comes with an out of the box support for Pact representation of contracts.
In other words instead of using the Groovy DSL you can use Pact files. In this section
we will present how to add such a support for your project.Pact contractWe will be working on the following example of a Pact contract. We’ve placed this file under
the src/test/resources/contracts folder.{
"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"
}
}
}Pact for producersOn the producer side you have add to your plugin configuration two additional dependencies.
One is the Spring Cloud Contract Pact support and the other represents the current
Pact version that you’re using.Maven<plugin>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-maven-plugin</artifactId>
<version>${spring-cloud-contract.version}</version>
<extensions>true</extensions>
<configuration>
<packageWithBaseClasses>com.example.fraud</packageWithBaseClasses>
</configuration>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-spec-pact</artifactId>
<version>${spring-cloud-contract.version}</version>
</dependency>
<dependency>
<groupId>au.com.dius</groupId>
<artifactId>pact-jvm-model</artifactId>
<version>2.4.18</version>
</dependency>
</dependencies>
</plugin>Gradleclasspath "org.springframework.cloud:spring-cloud-contract-spec-pact:${findProperty('verifierVersion') ?: verifierVersion}"
classpath 'au.com.dius:pact-jvm-model:2.4.18'When you execute the build of your application a test, looking more or less like this, will be generated@Test
public void validate_shouldMarkClientAsFraud() throws Exception {
// given:
MockMvcRequestSpecification request = given()
.header("Content-Type", "application/vnd.fraud.v1+json")
.body("{\"clientId\":\"1234567890\",\"loanAmount\":99999}");
// when:
ResponseOptions response = given().spec(request)
.put("/fraudcheck");
// then:
assertThat(response.statusCode()).isEqualTo(200);
assertThat(response.header("Content-Type")).isEqualTo("application/vnd.fraud.v1+json;charset=UTF-8");
// and:
DocumentContext parsedJson = JsonPath.parse(response.getBody().asString());
assertThatJson(parsedJson).field("rejectionReason").isEqualTo("Amount too high");
// and:
assertThat(parsedJson.read("$.fraudCheckStatus", String.class)).matches("FRAUD");
}and the stub looking like this{
"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"
}
}
}Pact for consumersOn the producer side you have add to your project dependencies two additional dependencies.
One is the Spring Cloud Contract Pact support and the other represents the current
Pact version that you’re using.Maven<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-contract-spec-pact</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>au.com.dius</groupId>
<artifactId>pact-jvm-model</artifactId>
<version>2.4.18</version>
<scope>test</scope>
</dependency>GradletestCompile "org.springframework.cloud:spring-cloud-contract-spec-pact"
testCompile 'au.com.dius:pact-jvm-model:2.4.18'Custom test generatorIf you want to generate tests for different languages than Java or you’re
not happy with the way we’re building Java tests for you then you can register
your own implementation to do that.Thanks to the interfacepackage 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<ContractMetadata> 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)
}you can register your own implementation that generates a test. Again, it’s enough to provide
a proper spring.factories file. Example:org.springframework.cloud.contract.verifier.builder.SingleTestGenerator=/
com.example.MyGeneratorCustom stub generatorIf you want to generate stubs for other stub server than WireMock it’s enough to
plug in your own implementation of this interface: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<Contract, String> 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)
}you can register your own implementation that generate Stubs. Again, it’s enough to provide
a proper spring.factories file. Example:# Stub converters
org.springframework.cloud.contract.verifier.converter.StubGenerator=\
org.springframework.cloud.contract.verifier.wiremock.DslToWireMockClientConverterThe default implementation is the WireMock stub generation.You can provide multiple stub generator implementations. That way for example from a single
DSL as input you can e.g. produce WireMock stubs and Pact files too!Custom Stub RunnerIf you decide to have a custom stub generation you also need a custom way of running
stubs with your different stub provider.Let us assume that you’re using Moco to build your stubs.
You wrote a proper stub generator and your stubs got placed in a JAR file.In order for Stub Runner to know how to run your stubs you have to define a custom
HTTP Stub server implementation. It can look like this: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<File> stubFiles) {
List<RunnerSetting> 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
String registeredMappings() {
return ""
}
@Override
boolean isAccepted(File file) {
return file.name.endsWith(".json")
}
}and just register it in your spring.factories fileorg.springframework.cloud.contract.stubrunner.HttpServerStub=\
org.springframework.cloud.contract.stubrunner.provider.moco.MocoHttpServerStubthat way you’ll be able to run stubs using Moco.If you don’t provide any implementation then the default one - WireMock based
will be picked. If you provide more than one then the first one on the list will be picked.Custom Stub DownloaderYou can customize the way your stubs are downloaded. It’s enough to create an
implementation of the StubDownloaderBuilderpackage com.example;
class CustomStubDownloaderBuilder implements StubDownloaderBuilder {
@Override
public StubDownloader build(final StubRunnerOptions stubRunnerOptions) {
return new StubDownloader() {
@Override
public Map.Entry<StubConfiguration, File> downloadAndUnpackStubJar(
StubConfiguration config) {
File unpackedStubs = retrieveStubs();
return new AbstractMap.SimpleEntry<>(
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
}
}and just register it in your spring.factories file# Example of a custom Stub Downloader Provider
org.springframework.cloud.contract.stubrunner.StubDownloaderBuilder=\
com.example.CustomStubDownloaderBuilderthat way you’ll be able to pick a folder with the source of your stubs.If you don’t provide any implementation then the default one will be picked.
If you provide repositoryRoot property or workOffline flag then Aether based
that will download stubs from a remote repo will be picked. If you don’t provide these
values then the ClasspathStubProvider will be picked that will scan the classpath.
If you provide more than one, then the first one on the list will be picked.Spring Cloud Contract WireMockModules giving you the possibility to use
WireMock in a Spring Boot application. Check out the
samples
for more details.If you have a Spring Boot application that uses Tomcat as an embedded
server, for example (the default with spring-boot-starter-web), then
you can simply add spring-cloud-contract-wiremock to your classpath
and add @AutoConfigureWireMock 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’s a simple example:@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!");
}
}To start the stub server on a different port use @AutoConfigureWireMock(port=9999) (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 @AutoConfigureWireMock adds a bean of type WiremockConfiguration 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.Registering Stubs AutomaticallyIf you use @AutoConfigureWireMock then it will register WireMock
JSON stubs from the file system or classpath, by default from
file:src/test/resources/mappings. You can customize the locations
using the stubs attribute in the annotation, which can be a resource
pattern (ant-style) or a directory, in which case */.json is
appended. Example:@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!");
}
}Actually WireMock always loads mappings from
src/test/resources/mappingsas well as the custom locations in the
stubs attribute. To change this behaviour you have to also specify a
files root as described next.Using Files to Specify the Stub BodiesWireMock 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 src/test/resources/__files by
default. To customize this location you can set the files attribute
in the @AutoConfigureWireMock annotation to the location of the
parent directory (i.e. the place __files is a
subdirectory). You can use Spring resource notation to refer to
file:… or classpath:… 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.when you configure the files 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 files has no
effect on the stubs loaded explicitly from the stubs attribute.Alternative: Using JUnit RulesFor a more conventional WireMock experience, using JUnit @Rules to
start and stop the server, just use the WireMockSpring convenience
class to obtain an Options instance:@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!");
}
}The use @ClassRule means that the server will shut down after all the methods in this class.Relaxed SSL Validation for Rest TemplateWireMock 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’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’s not open to you then you can ask Spring to configure
an HTTP client that ignores SSL validation errors (just for tests).To make this work with minimum fuss you need to be using the Spring Boot RestTemplateBuilder in your app,
e.g.@Bean
public RestTemplate restTemplate(RestTemplateBuilder builder) {
return builder.build();
}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
@AutoConfigureWireMock annotation (or the stub runner). If you are using the JUnit @Rule approach you need
to add the @AutoConfigureHttpClient annotation as well:@RunWith(SpringRunner.class)
@SpringBootTest("app.baseUrl=https://localhost:6443")
@AutoConfigureHttpClient
public class WiremockHttpsServerApplicationTests {
@ClassRule
public static WireMockClassRule wiremock = new WireMockClassRule(
WireMockSpring.options().httpsPort(6443));
...
}If you are using spring-boot-starter-test then you will have the Apache HTTP client on the classpath and it will
be selected by the RestTemplateBuilder and configured to ignore SSL errors. If you are using the default java.net
client you don’t need the annotation (but it won’t do any harm). There is no support currently for other clients, but
it may be added in future releases.WireMock and Spring MVC MocksSpring Cloud Contract provides a convenience class that can load JSON WireMock stubs into a
Spring MockRestServiceServer. Here’s an example:@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("http://example.org").stubs("classpath:/stubs/resource.json")
.build();
// We're asserting if WireMock responded properly
assertThat(this.service.go()).isEqualTo("Hello World");
server.verify();
}
}The baseUrl is prepended to all mock calls, and the stubs()
method takes a stub path resource pattern as an argument. So in this
example the stub defined at /stubs/resource.json is loaded into the
mock server, so if the RestTemplate is asked to visit
http://example.org/ 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.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.Generating Stubs using RestDocsSpring RestDocs 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 @AutoConfigureRestDocs to have stubs
automatically in the restdocs output directory. For example:@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"));
}
}From this test will be generated a WireMock stub at
"target/snippets/stubs/resource.json". It matches all GET requests to
the "/resource" path.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.The main entry point for this is WireMockRestDocs.verify() which can
be used as a substitute for the document() convenience method. For
example:@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"));
}
}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 .jsonPath() to add additional matchers. The
JayWay documentation can help you
to get up to speed with JSON Path if it is unfamiliar to you.Instead of the jsonPath and contentType convenience methods, you
can also use the WireMock APIs to verify the request matches the
created stub. Example:@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("$.id"))
.stub("post-resource"));
}The WireMock API is rich - you can match headers, query parameters,
and request body by regex as well as by json path - so this can useful
to create stubs with a wider range of parameters. The above example
will generate a stub something like this:post-resource.json{
"request" : {
"url" : "/resource",
"method" : "POST",
"bodyPatterns" : [ {
"matchesJsonPath" : "$.id"
}]
},
"response" : {
"status" : 200,
"body" : "Hello World",
"headers" : {
"X-Application-Context" : "application:-1",
"Content-Type" : "text/plain"
}
}
}You can use either the wiremock() method or the jsonPath()
and contentType() methods to create request matchers, but not both.On the consumer side, you can make the resource.json generated above
available on the classpath (by publishing stubs as JARs for example).
After that, you can create a stub using WireMock in a
number of different ways, including as described above using
@AutoConfigureWireMock(stubs="classpath:resource.json").Generating Contracts using RestDocsAnother 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’re getting both the contracts and stubs.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.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’s why we suggest to do both.Let’s imagine the following test: this.mockMvc.perform(post("/foo")
.accept(MediaType.APPLICATION_PDF)
.accept(MediaType.APPLICATION_JSON)
.contentType(MediaType.APPLICATION_JSON)
.content("{\"foo\": 23 }"))
.andExpect(status().isOk())
.andExpect(content().string("bar"))
// first WireMock
.andDo(WireMockRestDocs.verify()
.jsonPath("$[?(@.foo >= 20)]")
.contentType(MediaType.valueOf("application/json"))
.stub("shouldGrantABeerIfOldEnough"))
// then Contract DSL documentation
.andDo(document("index", SpringCloudContractRestDocs.dslContract()));This will lead in the creation of the stub as presented in the previous
section, contract will get generated and a documentation file too.The contract will be called index.groovy and look more like this.import org.springframework.cloud.contract.spec.Contract
Contract.make {
request {
method 'POST'
url '/foo'
body('''
{"foo": 23 }
''')
headers {
header('''Accept''', '''application/json''')
header('''Content-Type''', '''application/json''')
}
}
response {
status 200
body('''
bar
''')
headers {
header('''Content-Type''', '''application/json;charset=UTF-8''')
header('''Content-Length''', '''3''')
}
testMatchers {
jsonPath('$[?(@.foo >= 20)]', byType())
}
}
}the generated document (example for Asciidoc) will contain a formatted contract
(the location of this file would be index/dsl-contract.adoc).MigrationsIn the following document we will write about necessary migration steps between versions.1.0.x → 1.1.xNew structure of generated stubsIn 1.1.x we have introduced a changed structure of generated stubs. So if you’ve
been using the following @AutoConfigureWireMock notation to use the stubs from classpath@AutoConfigureWireMock(stubs = "classpath:/customer-stubs/mappings", port = 8084)It will no longer work with the new stubs. You have to either change the location of stubs
to : classpath:…/META-INF/groupId/artifactId/version/mappings as follows@AutoConfigureWireMock(stubs = "classpath:customer-stubs/META-INF/travel.components/customer-contract/1.0.2-SNAPSHOT/mappings/", port = 8084)Or migrate to the new classpath based @AutoConfigureStubRunner.If however you don’t want to do that and you want to remain with the old structure
just set your plugin tasks accordingly. Example for the structure presented in the
snippet above.Maven<!-- start of pom.xml -->
<properties>
<!-- we don't want the verifier to do a jar for us -->
<spring.cloud.contract.verifier.skip>true</spring.cloud.contract.verifier.skip>
</properties>
<!-- ... -->
<!-- You need to set up the assembly plugin -->
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<executions>
<execution>
<id>stub</id>
<phase>prepare-package</phase>
<goals>
<goal>single</goal>
</goals>
<inherited>false</inherited>
<configuration>
<attach>true</attach>
<descriptor>${basedir}/src/assembly/stub.xml</descriptor>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
<!-- end of pom.xml -->
<!-- start of stub.xml-->
<assembly
xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3 http://maven.apache.org/xsd/assembly-1.1.3.xsd">
<id>stubs</id>
<formats>
<format>jar</format>
</formats>
<includeBaseDirectory>false</includeBaseDirectory>
<fileSets>
<fileSet>
<directory>${project.build.directory}/snippets/stubs</directory>
<outputDirectory>customer-stubs/mappings</outputDirectory>
<includes>
<include>**/*</include>
</includes>
</fileSet>
<fileSet>
<directory>${basedir}/src/test/resources/contracts</directory>
<outputDirectory>customer-stubs/contracts</outputDirectory>
<includes>
<include>**/*.groovy</include>
</includes>
</fileSet>
</fileSets>
</assembly>
<!-- end of stub.xml-->Gradletask copyStubs(type: Copy, dependsOn: 'generateWireMockClientStubs') {
// Preserve directory structure from 1.0.X of spring-cloud-contract
from "${project.buildDir}/resources/main/customer-stubs/META-INF/${project.group}/${project.name}/${project.version}"
into "${project.buildDir}/resources/main/customer-stubs"
}1.1.x → 1.2.xCustom <literal>HttpServerStub</literal>By introducing a method String registeredMappings() in the public interface
HttpServerStub, if you wrote a custom HttpServerStub implementation, you’ll
have to implement that method too. It should return a String representing
all mappings available in a single HttpServerStub. Related to
issue 355.New packages for generated testsThe flow for setting the generated tests package name will look like this:pick basePackageForTestsif basePackageForTests wasn’t set pick the package from baseClassForTestsif baseClassForTests wasn’t set pick packageWithBaseClassesif nothing got set pick the default org.springframework.cloud.contract.verifier.tests valueRelated to
issue 260.New methods in TemplateProcessorIn order to add support for fromRequest.path some methods had to be added to the
TemplateProcessor interface.Related to
issue 388.LinksHere you can find interesting links related to Spring Cloud Contract Verifier:Spring Cloud Contract Github RepositorySpring Cloud Contract SamplesSpring Cloud Contract DocumentationAccurest Legacy DocumentationSpring Cloud Contract Stub Runner DocumentationSpring Cloud Contract Stub Runner Messaging DocumentationSpring Cloud Contract GitterSpring Cloud Contract Maven PluginSpring Cloud Contract WJUG Presentation by Marcin Grzejszczak