When using Pact you can use the Pact Broker +to store and share Pact definitions. Starting from Spring Cloud Contract +2.0.0 one can fetch Pact files from the Pact Broker to generate +tests and stubs.
As a prerequisite the Pact Converter and Pact Stub Downloader
+are required. You have to add it via the spring-cloud-contract-pact dependency.
+You can read more about it in the Section 10.1.1, “Pact Converter” section.
![[Important]](images/important.png) | Important |
|---|---|
Pact follows the Consumer Contract convention. That means +that the Consumer creates the Pact definitions first, then +shares the files with the Producer. Those expectations are generated +from the Consumer’s code and can break the Producer if the expectation +is not met. |
The consumer uses Pact framework to generate Pact files. The +Pact files are sent to the Pact Broker. An example of such +setup can be found here.
For the producer, to use the Pact files from the Pact Broker, we can reuse the
+same mechanism we use for external contracts. We route Spring Cloud Contract
+to use the Pact implementation via the URL that contains
+the pact:// protocol. It’s enough to pass the URL to the
+Pact Broker.
Maven. +
<plugin> + <groupId>org.springframework.cloud</groupId> + <artifactId>spring-cloud-contract-maven-plugin</artifactId> + <version>${spring-cloud-contract.version}</version> + <extensions>true</extensions> + <configuration> + <!-- Base class mappings etc. --> + + <!-- We want to pick contracts from a Git repository --> + <contractsRepositoryUrl>pact://http://localhost:8085</contractsRepositoryUrl> + + <!-- We reuse the contract dependency section to set up the path + to the folder that contains the contract definitions. In our case the + path will be /groupId/artifactId/version/contracts --> + <contractDependency> + <groupId>${project.groupId}</groupId> + <artifactId>${project.artifactId}</artifactId> + <!-- When + is passed, a latest tag will be applied when fetching pacts --> + <version>+</version> + </contractDependency> + + <!-- The contracts mode can't be classpath --> + <contractsMode>REMOTE</contractsMode> + </configuration> + <!-- Don't forget to add spring-cloud-contract-pact to the classpath! --> + <dependencies> + <dependency> + <groupId>org.springframework.cloud</groupId> + <artifactId>spring-cloud-contract-pact</artifactId> + <version>${spring-cloud-contract.version}</version> + </dependency> + </dependencies> +</plugin>
+
Gradle. +
buildscript {
+ repositories {
+ //...
+ }
+
+ dependencies {
+ // ...
+ // Don't forget to add spring-cloud-contract-pact to the classpath!
+ classpath "org.springframework.cloud:spring-cloud-contract-pact:${contractVersion}"
+ }
+}
+
+contracts {
+ // When + is passed, a latest tag will be applied when fetching pacts
+ contractDependency {
+ stringNotation = "${project.group}:${project.name}:+"
+ }
+ contractRepository {
+ repositoryUrl = "pact://http://localhost:8085"
+ }
+ // The mode can't be classpath
+ contractsMode = "REMOTE"
+ // Base class mappings etc.
+}+
With such a setup:
- Pact files will be downloaded from the Pact Broker
- Spring Cloud Contract will convert the Pact files into tests and stubs
- The JAR with the stubs gets automatically created as usual
In the scenario where you don’t want to do Consumer Contract approach +(for every single consumer define the expectations) but you’d prefer +to do Producer Contracts (the producer provides the contracts and +publishes stubs), it’s enough to use Spring Cloud Contract with +Stub Runner option.
First, remember to add Stub Runner and Spring Cloud Contract Pact module +as test dependencies.
Maven. +
<dependencyManagement> + <dependencies> + <dependency> + <groupId>org.springframework.cloud</groupId> + <artifactId>spring-cloud-dependencies</artifactId> + <version>${spring-cloud.version}</version> + <type>pom</type> + <scope>import</scope> + </dependency> + </dependencies> +</dependencyManagement> + +<!-- Don't forget to add spring-cloud-contract-pact to the classpath! --> +<dependencies> + <!-- ... --> + <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-contract-pact</artifactId> + <scope>test</scope> + </dependency> +</dependencies>
+
Gradle. +
dependencyManagement {
+ imports {
+ mavenBom "org.springframework.cloud:spring-cloud-dependencies:${springCloudVersion}"
+ }
+}
+
+dependencies {
+ //...
+ testCompile("org.springframework.cloud:spring-cloud-starter-contract-stub-runner")
+ // Don't forget to add spring-cloud-contract-pact to the classpath!
+ testCompile("org.springframework.cloud:spring-cloud-contract-pact")
+}+
Next, just pass the URL of the Pact Broker to repositoryRoot, prefixed
+with pact:// protocol. E.g. pact://http://localhost:8085
@RunWith(SpringRunner.class) +@SpringBootTest +@AutoConfigureStubRunner(stubsMode = StubRunnerProperties.StubsMode.REMOTE, + ids = "com.example:beer-api-producer-pact", + repositoryRoot = "pact://http://localhost:8085") +public class BeerControllerTest { + //Inject the port of the running stub + @StubRunnerPort("beer-api-producer-pact") int producerPort; + //... +}
With such a setup:
- Pact files will be downloaded from the Pact Broker
- Spring Cloud Contract will convert the Pact files into stub definitions
- The stub servers will be started and fed with stubs
For more information about Pact support you can go to +the Section 10.7, “Using the Pact Stub Downloader” section.