Table of Contents
Documentation Authors: Adam Dudczak, Mathias Düsterhöft, Marcin Grzejszczak, Dennis Kieselhorst, Jakub Kubryński, Karol Lassak, Olga Maciaszek-Sharma, Mariusz Smykuła, Dave Syer
1.1.4.RELEASE
What you always need is confidence in pushing new features into a new application or service in a distributed system. This project provides support for Consumer Driven Contracts and service schemas in Spring applications, covering a range of options for writing tests, publishing them as assets, asserting that a contract is kept by producers and consumers, for HTTP and message-based interactions.
Tip | |
---|---|
The 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:
Spring Cloud Contract Verifier moves TDD to the level of software architecture.
Let us assume that we have a system comprising of multiple microservices:
If we wanted to test the application in top left corner if it can communicate with other services then we could do one of two things:
Both have their advantages but also a lot of disadvantages. Let’s focus on the latter.
Deploy all microservices and perform end to end tests
Advantages:
Disadvantages:
Mock other microservices in unit / integration tests
Advantages:
Disadvantages:
To solve the aforementioned issues Spring Cloud Contract Verifier with Stub Runner were created. Their main idea is to give you very fast feedback, without the need to set up the whole world of microservices. If you work on stubs then the only applications you need are those that your application is using directly.
Spring 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.
The main purposes of Spring Cloud Contract Verifier with Stub Runner are:
Important | |
---|---|
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. |
As 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.*` */
Spring Cloud Contract will generate stubs, which you can use during client side testing. You will have a WireMock instance / Messaging route up and running that simulates the service Y. You would like to feed that instance with a proper stub definition.
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.
Being 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"); }
Let’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.
Tip | |
---|---|
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 repository |
If using the SNAPSHOT / Milestone / Release Candidate versions please add the following section to your
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>
Gradle.
repositories { mavenCentral() mavenLocal() maven { url "http://repo.spring.io/snapshot" } maven { url "http://repo.spring.io/milestone" } maven { url "http://repo.spring.io/release" } }
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 implementation
At 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 locally
We’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-repo
define the contract locally in the repo of Fraud Detection service
As 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.
Important | |
---|---|
We’re placing the contract under |
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!
Tip | |
---|---|
It’s really important that you understand the map notation to set up contracts. Please read the Groovy docs regarding JSON |
The aforementioned contract is an agreement between two sides that:
if an HTTP request is sent with
PUT
on an endpoint /fraudcheck
client.id
matching the regular expression [0-9]{10}
and loanAmount
equal to 99999
Content-Type
equal to application/vnd.fraud.v1+json
then an HTTP response would be sent to the consumer that
200
fraudCheckStatus
field containing a value FRAUD
and the rejectionReason
field having value Amount too high
Content-Type
header with a value of application/vnd.fraud.v1+json
Once we’re ready to check the API in practice in the integration tests we need to just install the stubs locally
add the Spring Cloud Contract Verifier plugin
We 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:
We 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 -DskipTests
In 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:1.5.4.BUILD-SNAPSHOT:repackage (default) @ http-server --- [INFO] [INFO] --- maven-install-plugin:2.5.2:install (default-install) @ http-server --- [INFO] Installing /some/path/http-server/target/http-server-0.0.1-SNAPSHOT.jar to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT.jar [INFO] Installing /some/path/http-server/pom.xml to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT.pom [INFO] Installing /some/path/http-server/target/http-server-0.0.1-SNAPSHOT-stubs.jar to /path/to/your/.m2/repository/com/example/http-server/0.0.1-SNAPSHOT/http-server-0.0.1-SNAPSHOT-stubs.jar
This 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.jar
It’s confirming that the stubs of the http-server
have been installed in the local repository.
run the integration tests
In order to profit from the Spring Cloud Contract Stub Runner functionality of automatic stub downloading you have to do the following in our consumer side project (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 PR
What we did until now is an iterative process. We can play around with the contract, install it locally and work on the consumer side until we’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.
As a developer of the Fraud Detection server (a server to the Loan Issuance service):
initial implementation
As 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 PR
git checkout -b contract-change-pr master git pull https://your-git-server.com/server-side-fork.git contract-change-pr
You 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>
Important | |
---|---|
We’ve decided to use the "convention based" naming by setting the |
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 implementation
Now 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 app
Once you’ve finished your work it’s time to deploy your change. First merge the branch
git checkout master git merge --no-ff contract-change-pr git push origin master
Then we assume that your CI would run sth like ./mvnw clean deploy
which would publish both the application and the stub artifcats.
As a developer of the Loan Issuance service (a consumer of the Fraud Detection server):
merge branch to master
git checkout master git merge --no-ff contract-change-pr
work online
Now you can disable the offline work for Spring Cloud Contract Stub Runner and provide where the repository with your stubs is placed. At this moment the stubs of the server side will be automatically downloaded from Nexus / Artifactory.
You can switch off the value of the 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-snapshot
And that’s it!
The 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
.
Below you can find some resources related to Spring Cloud Contract Verifier and Stub Runner. Note that some can be outdated since the Spring Cloud Contract Verifier project is under constant development.
You can check out the video from the Warsaw JUG about Spring Cloud Contract:
Here you can find some samples.
In order to use Spring Cloud Contract Verifier with WireMock you have to use Gradle or Maven plugin.
Warning | |
---|---|
If you want to use Spock in your projects you have to add separately
the |
buildscript { repositories { mavenCentral() } dependencies { classpath "org.springframework.boot:spring-boot-gradle-plugin:${springboot_version}" classpath "org.springframework.cloud:spring-cloud-contract-gradle-plugin:${verifier_version}" } } apply plugin: 'groovy' apply plugin: 'spring-cloud-contract' dependencyManagement { imports { mavenBom "org.springframework.cloud:spring-cloud-contract-dependencies:${verifier_version}" } } dependencies { testCompile 'org.codehaus.groovy:groovy-all:2.4.6' // example with adding Spock core and Spock Spring testCompile 'org.spockframework:spock-core:1.0-groovy-2.4' testCompile 'org.spockframework:spock-spring:1.0-groovy-2.4' testCompile 'org.springframework.cloud:spring-cloud-starter-contract-verifier' }
By default Rest Assured 2.x is added to the classpath. However in order to give the users the opportunity to use Rest Assured 3.x it’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 "io.rest-assured:rest-assured:3.0.2" classpath "io.rest-assured:spring-mock-mvc:3.0.2" } } depenendencies { // all dependencies // you can exclude rest-assured from spring-cloud-contract-verifier testCompile "io.rest-assured:rest-assured:3.0.2" testCompile "io.rest-assured:spring-mock-mvc:3.0.2" }
That way the plugin will automatically see that Rest Assured 3.x is present on the classpath and will modify the imports accordingly.
Add 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" } } }
By 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 structure
src/test/resources/contracts/myservice/shouldCreateUser.groovy src/test/resources/contracts/myservice/shouldReturnUser.groovy
Spring Cloud Contract Verifier will create test class defaultBasePackage.MyService
with two methods
shouldCreateUser()
shouldReturnUser()
Plugin 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 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("${project.buildDir}/stubs") // the following properties are used when you want to provide where the JAR with contract lays contractDependency { stringNotation = '' } contractsPath = '' contractsWorkOffline = false contractRepository { cacheDownloadedContracts(true) } } tasks.create(type: Jar, name: 'verifierStubsJar', dependsOn: 'generateClientStubs') { baseName = project.name classifier = contracts.stubsSuffix from contractVerifier.stubsOutputDir } project.artifacts { archives task } tasks.create(type: Copy, name: 'copyContracts') { from contracts.contractsDslDir into contracts.stubsOutputDir } verifierStubsJar.dependsOn 'copyContracts' publishing { publications { stubs(MavenPublication) { artifactId project.name artifact verifierStubsJar } } }
To change default configuration just add contracts
snippet to your Gradle config
contracts { testMode = 'MockMvc' baseClassForTests = 'org.mycompany.tests' generatedTestSourcesDir = project.file('src/generatedContract') }
spock.lang.Specification
if using Spock tests.$rootDir/src/test/resources/contracts
$buildDir/generated-test-sources/contractVerifier
The following properties are used when you want to provide where the JAR with contract lays
groupid:artifactid:version:classifier
coordinates. You can use the contractDependency
closure to set it upgroupid/artifactid
where groupid
will be slash separated. Otherwise will scan contracts under provided directoryWhen 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.
If your base classes differ between contracts you can tell the Spring Cloud Contract plugin which class should get extended by the autogenerated tests. You have two options:
packageWithBaseClasses
baseClassMappings
Convention
The 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'
Mapping
You 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
.
To ensure that provider side is complaint with defined contracts, you need to invoke:
./gradlew generateContractTests test
In consumer service you need to configure Spring Cloud Contract Verifier plugin in exactly the same way as in case of provider. If you don’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 generateClientStubs
Note 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.
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>${spring-cloud-contract.version}</version> <extensions>true</extensions> <configuration> <packageWithBaseClasses>com.example.fraud</packageWithBaseClasses> </configuration> </plugin>
You can read more in the Spring Cloud Contract Maven Plugin Docs
By default Rest Assured 2.x is added to the classpath. However in order to give the users the opportunity to use Rest Assured 3.x it’s enough to add it to the plugins classpath.
<plugin> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-contract-maven-plugin</artifactId> <version>${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>io.rest-assured</groupId> <artifactId>rest-assured</artifactId> <version>3.0.2</version> <scope>compile</scope> </dependency> <dependency> <groupId>io.rest-assured</groupId> <artifactId>spring-mock-mvc</artifactId> <version>3.0.2</version> <scope>compile</scope> </dependency> </dependencies> </plugin> <dependencies> <!-- all dependencies --> <!-- you can exclude rest-assured from spring-cloud-contract-verifier --> <dependency> <groupId>io.rest-assured</groupId> <artifactId>rest-assured</artifactId> <version>3.0.2</version> <scope>test</scope> </dependency> <dependency> <groupId>io.rest-assured</groupId> <artifactId>spring-mock-mvc</artifactId> <version>3.0.2</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.
For 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>
By 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 structure
src/test/resources/contracts/myservice/shouldCreateUser.groovy src/test/resources/contracts/myservice/shouldReturnUser.groovy
Spring Cloud Contract Verifier will create test class defaultBasePackage.MyService
with two methods
- shouldCreateUser()
- shouldReturnUser()
Plugin 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.
To 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>
MockMvc
which is based on Spring’s MockMvc. It can also be changed to JaxRsClient
or to Explicit
for real HTTP calls.org.springframework.cloud.verifier.tests
.spock.lang.Specification
if using Spock tests./src/test/resources/contracts
.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 baseClassForTestscontractPackageRegex
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 use
groupid/artifactid
where gropuid
is slash separated.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 contracts
+
or 1.0.0.BUILD-SNAPSHOT
won’t get cached).
By default this feature is turned on.When using Spring Cloud Contract Verifier in default MockMvc you need to create a base specification for all generated acceptance tests. In this class you need to point to endpoint which should be verified.
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.
If your base classes differ between contracts you can tell the Spring Cloud Contract plugin which class should get extended by the autogenerated tests. You have two options:
packageWithBaseClasses
baseClassMappings
Convention
The 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>
Mapping
You 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
.
Spring 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 test
In case you see the following exception while using STS
when 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$11.call(MavenImpl.java:1362) at ... org.eclipse.core.internal.jobs.Worker.run(Worker.java:55) Caused by: java.lang.NullPointerException at org.eclipse.m2e.core.internal.builder.plexusbuildapi.EclipseIncrementalBuildContext.hasDelta(EclipseIncrementalBuildContext.java:53) at org.sonatype.plexus.build.incremental.ThreadBuildContext.hasDelta(ThreadBuildContext.java:59) at
In order to fix this issue just provide the following section in your pom.xml
<build> <pluginManagement> <plugins> <!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself. --> <plugin> <groupId>org.eclipse.m2e</groupId> <artifactId>lifecycle-mapping</artifactId> <version>1.0.0</version> <configuration> <lifecycleMappingMetadata> <pluginExecutions> <pluginExecution> <pluginExecutionFilter> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-contract-maven-plugin</artifactId> <versionRange>[1.0,)</versionRange> <goals> <goal>convert</goal> </goals> </pluginExecutionFilter> <action> <execute /> </action> </pluginExecution> </pluginExecutions> </lifecycleMappingMetadata> </configuration> </plugin> </plugins> </pluginManagement> </build>
You can actually use the Spring Cloud Contract Verifier also for the consumer side!
You can use the plugin so that it only converts the contracts and generates the stubs.
To achieve that you need to configure Spring Cloud Contract Verifier plugin in exactly
the same way as in case of provider. You need to copy contracts stored in
src/test/resources/contracts
and generate WireMock json stubs using:
mvn generateStubs
command. By default generated WireMock mapping is
stored in directory target/mappings
. Your project should create from
this generated mappings additional artifact with classifier stubs
for
easy deploy to maven repository.
Sample configuration:
<plugin> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-contract-maven-plugin</artifactId> <version>${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.
It’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.groovy
Such tree will cause Spring Cloud Contract Verifier generating WireMock’s scenario with name scenario1
and three steps:
Started
pointing to:Step1
pointing to:Step2
which will close the scenario.More details about WireMock scenarios can be found under http://wiremock.org/stateful-behaviour.html
Spring Cloud Contract Verifier will also generate tests with guaranteed order of execution.
The 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 optional
If 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 stubs
If you create a separate artifactid then you can set it up in whatever way you wish. For example by having no dependencies at all.
Exclude dependencies on the consumer side
As a consumer, if you add the stub dependency to your classpath you can explicitly exclude the unwanted dependencies.
Spring Cloud Contract Verifier allows you to verify your application that uses messaging as means of communication. All of our integrations are working with Spring but you can also create one yourself and use it.
You can use one of the four integration configurations:
Since 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.
Important | |
---|---|
Remember to put |
Important | |
---|---|
If you want to use Spring Cloud Stream remember to add a
|
Maven.
<dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-stream-test-support</artifactId> <scope>test</scope> </dependency>
Gradle.
testCompile "org.springframework.cloud:spring-cloud-stream-test-support"
The 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; ... }
Note | |
---|---|
If your tests require stubs as well, then
|
Having 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:
Important | |
---|---|
The destination passed to |
Example for Camel:
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") '''
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") """
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() '''
Unlike 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>Dalston.BUILD-SNAPSHOT</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement>
Gradle.
ext { contractsDir = file("mappings") stubsOutputDirRoot = file("${project.buildDir}/production/${project.name}-stubs/") } // Automatically added by plugin: // copyContracts - copies contracts to the output folder from which JAR will be created // verifierStubsJar - JAR with a provided stub suffix // the presented publication is also added by the plugin but you can modify it as you wish publishing { publications { stubs(MavenPublication) { artifactId "${project.name}-stubs" artifact verifierStubsJar } } }
One of the issues that you could have encountered while using Spring Cloud Contract Verifier was to pass the generated WireMock JSON stubs from the server side to the client side (or various clients). The same takes place in terms of client side generation for messaging.
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.
Add 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>
Gradle.
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" } }
The easiest approach would be to centralize the way stubs are kept. For example you can keep them as JARs in a Maven repository.
Tip | |
---|---|
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}/${project.version}/contracts</outputDirectory> <includes> <include>**/*.groovy</include> </includes> </fileSet> </fileSets> </assembly>
Gradle.
ext { contractsDir = file("mappings") stubsOutputDirRoot = file("${project.buildDir}/production/${project.name}-stubs/") } // Automatically added by plugin: // copyContracts - copies contracts to the output folder from which JAR will be created // verifierStubsJar - JAR with a provided stub suffix // the presented publication is also added by the plugin but you can modify it as you wish publishing { publications { stubs(MavenPublication) { artifactId "${project.name}-stubs" artifact verifierStubsJar } } }
Runs 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.
You can pick the following options of acquiring stubs
org.springframework.cloud.contract.stubrunner.StubDownloaderBuilder
for full customizationThe latter example is described in the Custom Stub Runner section.
If 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")
If 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 classpath
Maven.
<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>
Gradle.
testCompile("com.example:beer-api-producer-restdocs:0.0.1-SNAPSHOT:stubs") { transitive = false } testCompile("com.example.foo:bar:1.0.0:superstubs") { transitive = false }
Then the following locations on your classpath will get scanned. For com.example:beer-api-producer-restdocs
and com.example.foo:bar
Tip | |
---|---|
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.groovy
To 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.json
By maintaining this structure classpath gets scanned and you can profit from the messaging / HTTP stubs without the need to download artifacts.
Important | |
---|---|
There might be a problem with StubRunner shutting down ports between tests. You might
have a situation in which you get port conflicts. As long as you use the same context across tests
everything works fine. But when the context are different (e.g. different stubs or different profiles)
then you have to either use |
You 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'
Stubs are defined in JSON documents, whose syntax is defined in WireMock documentation
Example:
{ "request": { "method": "GET", "url": "/ping" }, "response": { "status": 200, "body": "pong", "headers": { "Content-Type": "text/plain" } } }
Every stubbed collaborator exposes list of defined mappings under __/admin/
endpoint.
Stub 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:
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") 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' }
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.
Important | |
---|---|
To use the JUnit rule together with messaging you have to provide an implementation of the
|
The stub downloader honors Maven settings for a different local repository folder. Authentication details for repositories and profiles are currently not taken into account, so you need to specify it using the properties mentioned above.
You can also run your stubs on fixed ports. You can do it in two different ways. One is to pass it in the properties, and the other via fluent API of JUnit rule.
When 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());
Sets 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=${stubrunner.runningstubs.fraudDetectionServer.port}']) @AutoConfigureStubRunner @DirtiesContext @ActiveProfiles("test") class StubRunnerConfigurationSpec extends Specification { @Autowired StubFinder stubFinder @Autowired Environment environment @Value('${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 } @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: false
Instead 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.port
stubrunner.runningstubs.bar.port
Which you can reference in your code.
Stub Runner can integrate with Spring Cloud.
For real life examples you can check the
The most important feature of Stub Runner Spring Cloud
is the fact that it’s stubbing
DiscoveryClient
Ribbon
ServerList
that 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 pass
def 'should make service discovery work'() { expect: 'WireMocks are running' "${stubFinder.findStubUrl('loanIssuance').toString()}/name".toURL().text == 'loanIssuance' "${stubFinder.findStubUrl('fraudDetectionServer').toString()}/name".toURL().text == 'fraudDetectionServer' and: 'Stubs can be reached via load service discovery' restTemplate.getForObject('http://loanIssuance/name', String) == 'loanIssuance' restTemplate.getForObject('http://someNameThatShouldMapFraudDetectionServer/name', String) == 'fraudDetectionServer' }
for the following configuration file
spring.cloud: zookeeper.enabled: false consul.enabled: false eureka.client.enabled: false stubrunner: camel.enabled: false idsToServiceIds: ivyNotation: someValueInsideYourCode fraudDetectionServer: someNameThatShouldMapFraudDetectionServer
In 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"); }
You 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 false
Tip | |
---|---|
By default all service discovery will be stubbed. That means that regardless of the fact if you have
an existing |
Spring Cloud Contract Stub Runner Boot is a Spring Boot application that exposes REST endpoints to trigger the messaging labels and to access started WireMock servers.
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.
Just add the
compile "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.
Starting 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.yml.
stubrunner: workOffline: true ids: - com.example:beer-api-producer:+:9876
and then just call spring cloud stubrunner
from your terminal window to start
the Stub Runner server. It will be available at port 8750
.
/stubs
- returns a list of all running stubs in ivy:integer
notation/stubs/{ivy}
- returns a port for the given ivy
notation (when calling the endpoint ivy
can also be artifactId
only)For Messaging
/triggers
- returns a list of all running labels in ivy : [ label1, label2 …]
notation/triggers/{label}
- executes a trigger with label
/triggers/{ivy}/{label}
- executes a trigger with label
for the given ivy
notation (when calling the endpoint ivy
can also be artifactId
only)@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=") } }
One of the possibilities of using Stub Runner Boot is to use it as a feed of stubs for "smoke-tests". What does it mean? Let’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 mapping
That way your deployed application can send requests to started WireMock servers via the service
discovery. Most likely points 1-3 could be set by default in 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.
There are cases in which 2 consumers of the same endpoint want to have 2 different responses.
Tip | |
---|---|
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-service
request { url '/foo' method GET() } response { status 200 body( foo: "foo" } }
Consumer bar-service
request { 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.groovy
Being 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.
Some of the properties that are repetitive can be set using system properties or configuration properties (for Spring). Here are their names with their default values:
Property name | Default value | Description |
---|---|---|
stubrunner.minPort | 10000 | Minimal value of a port for a started WireMock with stubs |
stubrunner.maxPort | 15000 | Minimal value of a port for a started WireMock with stubs |
stubrunner.repositoryRoot | Maven repo url. If blank then will call the local maven repo | |
stubrunner.classifier | stubs | Default classifier for the stub artifacts |
stubrunner.workOffline | false | If true then will not contact any remote repositories to download stubs |
stubrunner.ids | Array of Ivy notation stubs to download | |
stubrunner.username | Optional username to access the tool that stores the JARs with stubs | |
stubrunner.password | Optional password to access the tool that stores the JARs with stubs | |
stubrunner.stubsPerConsumer | false | Set to |
stubrunner.consumerName | If you want to use stubs per consumer and want to override the consumer name just change this value |
You can provide the stubs to download via the stubrunner.ids
system property. They follow the following pattern:
groupId:artifactId:version:classifier:port
version
, classifier
and port
are optional.
port
then a random one will be pickedclassifier
then the default one will be taken. (NOTE that you can pass an empty classifier like this groupId:artifactId:version:
)version
then the +
will be passed and the latest one will be downloadedWhere port
means the port of the WireMock server.
Important | |
---|---|
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 has the functionality to run the published stubs in memory. It can integrate with the following frameworks out of the box
It also provides points of entry to integrate with any other solution on the market.
Important | |
---|---|
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 |
To 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:
stubFinder.trigger('org.springframework.cloud.contract.verifier.stubs:camelService', 'return_book_1')
Spring 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.
It’s enough to have both Apache Camel and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with @AutoConfigureStubRunner
.
If you need to disable this functionality just pass stubrunner.camel.enabled=false
property.
Let 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.xml
And the stubs contain the following structure:
├── META-INF │ └── MANIFEST.MF └── repository ├── accurest │ ├── bookDeleted.groovy │ ├── bookReturned1.groovy │ └── bookReturned2.groovy └── mappings
Let’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 2
Contract.make { label 'return_book_2' input { messageFrom('jms:input') messageBody([ bookName: 'foo' ]) messageHeaders { header('sample', 'header') } } outputMessage { sentTo('jms:output') body([ bookName: 'foo' ]) headers { header('BOOK-NAME', 'foo') } } }
So as to trigger a message via the return_book_1
label we’ll use the StubTigger
interface as follows
stubFinder.trigger('return_book_1')
Next we’ll want to listen to the output of the message sent to jms:output
Exchange receivedMessage = camelContext.createConsumerTemplate().receive('jms:output', 5000)
And the received message would pass the following assertions
receivedMessage != null assertThatBodyContainsBookNameFoo(receivedMessage.in.body) receivedMessage.in.headers.get('BOOK-NAME') == 'foo'
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:output
Exchange receivedMessage = camelContext.createConsumerTemplate().receive('jms:output', 5000)
And the received message would pass the following assertions
receivedMessage != null assertThatBodyContainsBookNameFoo(receivedMessage.in.body) receivedMessage.in.headers.get('BOOK-NAME') == 'foo'
Spring 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.
It’s enough to have both Spring Integration and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with @AutoConfigureStubRunner
.
If you need to disable this functionality just pass stubrunner.integration.enabled=false
property.
Let 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.xml
And the stubs contain the following structure:
├── META-INF │ └── MANIFEST.MF └── repository ├── accurest │ ├── bookDeleted.groovy │ ├── bookReturned1.groovy │ └── bookReturned2.groovy └── mappings
Let’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 2
Contract.make { label 'return_book_2' input { messageFrom('input') messageBody([ bookName: 'foo' ]) messageHeaders { header('sample', 'header') } } outputMessage { sentTo('output') body([ bookName: 'foo' ]) headers { header('BOOK-NAME', 'foo') } } }
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>
So as to trigger a message via the return_book_1
label we’ll use the StubTigger
interface as follows
stubFinder.trigger('return_book_1')
Next we’ll want to listen to the output of the message sent to output
Message<?> receivedMessage = messaging.receive('outputTest')
And the received message would pass the following assertions
receivedMessage != null assertJsons(receivedMessage.payload) receivedMessage.headers.get('BOOK-NAME') == 'foo'
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 output
Message<?> receivedMessage = messaging.receive('outputTest')
And the received message would pass the following assertions
receivedMessage != null assertJsons(receivedMessage.payload) receivedMessage.headers.get('BOOK-NAME') == 'foo'
Spring 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.
Warning | |
---|---|
In Stub Runner’s integration with Stream the |
Important | |
---|---|
If you want to use Spring Cloud Stream remember to add a
|
Maven.
<dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-stream-test-support</artifactId> <scope>test</scope> </dependency>
Gradle.
testCompile "org.springframework.cloud:spring-cloud-stream-test-support"
It’s enough to have both Spring Cloud Stream and Spring Cloud Contract Stub Runner on classpath.
Remember to annotate your test class with @AutoConfigureStubRunner
.
If you need to disable this functionality just pass stubrunner.stream.enabled=false
property.
Let 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.xml
And the stubs contain the following structure:
├── META-INF │ └── MANIFEST.MF └── repository ├── accurest │ ├── bookDeleted.groovy │ ├── bookReturned1.groovy │ └── bookReturned2.groovy └── mappings
Let’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 2
Contract.make { label 'return_book_2' input { messageFrom('bookStorage') messageBody([ bookName: 'foo' ]) messageHeaders { header('sample', 'header') } } outputMessage { sentTo('returnBook') body([ bookName: 'foo' ]) headers { header('BOOK-NAME', 'foo') } } }
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: true
So as to trigger a message via the return_book_1
label we’ll use the StubTrigger
interface as follows
stubFinder.trigger('return_book_1')
Next we’ll want to listen to the output of the message sent to a channel whose destination
is returnBook
Message<?> receivedMessage = messaging.receive('returnBook')
And the received message would pass the following assertions
receivedMessage != null assertJsons(receivedMessage.payload) receivedMessage.headers.get('BOOK-NAME') == 'foo'
Since the route is set for you it’s enough to just send a message to the bookStorage
destination
.
messaging.send(new BookReturned('foo'), [sample: 'header'], 'bookStorage')
Next we’ll want to listen to the output of the message sent to returnBook
Message<?> receivedMessage = messaging.receive('returnBook')
And the received message would pass the following assertions
receivedMessage != null assertJsons(receivedMessage.payload) receivedMessage.headers.get('BOOK-NAME') == 'foo'
Spring 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.
It’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
.
Important | |
---|---|
If you already have Stream and Integration on the classpath you need
to disable them explicitly via |
Let 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.xml
And the stubs contain the following structure:
├── META-INF │ └── MANIFEST.MF └── contracts └── shouldProduceValidPersonData.groovy
Let’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: 0
So 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; }
Note | |
---|---|
The message is directly handed over to the |
Important | |
---|---|
Remember that inside the contract file you have to provide the fully qualified name to
the |
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.
Tip | |
---|---|
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
.
Warning | |
---|---|
Spring Cloud Contract Verifier doesn’t support XML properly. Please use JSON or help us implement this feature. |
Warning | |
---|---|
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 |
Warning | |
---|---|
Due to the fact that JSON structure can have any form it’s sometimes impossible to parse it properly when using
the |
You 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 ''') }
You 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.
Important | |
---|---|
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. |
Following 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 }
HTTP 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" ] } } '''
Minimal 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).
The 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
.
You can set the properties inside the body either via the value
method
value(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.
You 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 this
Contract dslWithOptionalsInString = Contract.make { priority 1 request { method POST() url '/users/password' headers { contentType(applicationJson()) } body( email: $(consumer(optional(regex(email()))), producer('[email protected]')), 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('[email protected]'))}]" ) } }
It is possible to provide optional parameters in your contract. It’s only possible to have optional parameter for the:
Example:
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('[email protected]')), callback_url: $(consumer(regex(hostname())), producer('http://partners.com')) ) } response { status 404 headers { header 'Content-Type': 'application/json' } body( code: value(consumer("123123"), producer(optional("123123"))) ) } }
By wrapping a part of the body with the optional()
method you are in fact creating a regular expression that should be present 0 or more times.
That way for the example above the following test would be generated if you pick Spock:
""" given: def request = given() .header("Content-Type", "application/json") .body('''{"email":"[email protected]","callback_url":"http://partners.com"}''') when: def response = given().spec(request) .post("/users/password") then: response.statusCode == 404 response.header('Content-Type') == 'application/json' and: DocumentContext parsedJson = JsonPath.parse(response.body.asString()) assertThatJson(parsedJson).field("['code']").matches("(123123)?") """
and the following stub:
''' { "request" : { "url" : "/users/password", "method" : "POST", "bodyPatterns" : [ { "matchesJsonPath" : "$[?(@.['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 } '''
It 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:
Contract
org.springframework.cloud.contract.spec.Contract.make { request { method 'PUT' url $(consumer(regex('^/api/[0-9]{2}$')), producer('/api/12')) headers { header 'Content-Type': 'application/json' } body '''\ [{ "text": "Gonna see you at Warsaw" }] ''' } response { body ( path: $(consumer('/api/12'), producer(regex('^/api/[0-9]{2}$'))), correlationId: $(consumer('1223456'), producer(execute('isProperCorrelationId($it)'))) ) status 200 } }
Base class
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 } }
Important | |
---|---|
You can’t use both a String and |
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 JSONNumber
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.
Important | |
---|---|
You have to provide both the consumer and the producer side
and the |
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);
The 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 URLfromRequest().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().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 contract
Contract contractDsl = Contract.make { request { method 'GET' url('/api/v1/xxxx') { queryParameters { parameter("foo", "bar") parameter("foo", "bar2") } } headers { header(authorization(), "secret") header(authorization(), "secret2") } body(foo: "bar", baz: 5) } response { status 200 headers { header(authorization(), "foo ${fromRequest().header(authorization())} bar") } body( url: fromRequest().url(), param: fromRequest().query("foo"), paramIndex: fromRequest().query("foo", 1), authorization: fromRequest().header("Authorization"), authorization2: fromRequest().header("Authorization", 1), fullBody: fromRequest().body(), responseFoo: fromRequest().body('$.foo'), responseBaz: fromRequest().body('$.baz'), responseBaz2: "Bla bla ${fromRequest().body('$.foo')} bla bla" ) } }
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("url").isEqualTo("/api/v1/xxxx"); assertThatJson(parsedJson).field("fullBody").isEqualTo("{\"foo\":\"bar\",\"baz\":5}"); assertThatJson(parsedJson).field("paramIndex").isEqualTo("bar2"); assertThatJson(parsedJson).field("responseFoo").isEqualTo("bar"); assertThatJson(parsedJson).field("authorization2").isEqualTo("secret2"); assertThatJson(parsedJson).field("responseBaz").isEqualTo(5); assertThatJson(parsedJson).field("responseBaz2").isEqualTo("Bla bla bar bla bla"); assertThatJson(parsedJson).field("param").isEqualTo("bar"); assertThatJson(parsedJson).field("authorization").isEqualTo("secret");
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" : "{\"url\":\"{{{request.url}}}\",\"param\":\"{{{request.query.foo.[0]}}}\",\"paramIndex\":\"{{{request.query.foo.[1]}}}\",\"authorization\":\"{{{request.headers.Authorization.[0]}}}\",\"authorization2\":\"{{{request.headers.Authorization.[1]}}}\",\"fullBody\":\"{{{escapejsonbody}}}\",\"responseFoo\":\"{{{jsonpath this '$.foo'}}}\",\"responseBaz\":{{{jsonpath this '$.baz'}}} ,\"responseBaz2\":\"Bla bla {{{jsonpath this '$.foo'}}} bla bla\"}", "headers" : { "Authorization" : "{{{request.headers.Authorization.[0]}}}" }, "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", "param" : "bar", "paramIndex" : "bar2", "authorization" : "secret", "authorization2" : "secret2", "fullBody" : "{\"foo\":\"bar\",\"baz\":5}", "responseFoo" : "bar", "responseBaz" : 5, "responseBaz2" : "Bla bla bar bla bla" }
Important | |
---|---|
This feature will work only with WireMock having version greater or equal to 2.5.1. We’re using WireMock’s
|
If 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 JSONNumber
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:
$.valueWithTypeMatch
- we’re just checking the whether the type is the same$.valueWithMin
- we’re checking the type and assert if the size is greater or equal to the min occurrence$.valueWithMax
- we’re checking the type and assert if the size is smaller or equal to the max occurrence$.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("$.duck"));
Important | |
---|---|
Notice that for the |
and the WireMock stub like this:
''' { "request" : { "urlPath" : "/get", "method" : "POST", "headers" : { "Content-Type" : { "matches" : "application/json.*" } }, "bodyPatterns" : [ { "matchesJsonPath" : "$[?(@.['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" : "{\\"duck\\":123,\\"alpha\\":\\"abc\\",\\"number\\":123,\\"aBoolean\\":true,\\"date\\":\\"2017-01-01\\",\\"dateTime\\":\\"2017-01-01T01:23:45\\",\\"time\\":\\"01:02:34\\",\\"valueWithoutAMatcher\\":\\"foo\\",\\"valueWithTypeMatch\\":\\"string\\",\\"valueWithMin\\":[1,2,3],\\"valueWithMax\\":[1,2,3],\\"valueWithMinMax\\":[1,2,3]}", "headers" : { "Content-Type" : "application/json" } } } '''
Important | |
---|---|
If you use a |
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 $.events
collection and assert it
via the byCommand(…)
method.
We support JAX-RS 2 Client API. Base class needs to define protected WebTarget webTarget
and server initialization, right now the only option how to test JAX-RS API is to start a web server.
Request with a body needs to have a content type set otherwise application/octet-stream
is going to be used.
In order to use JAX-RS mode, use the following settings:
testMode == 'JAXRSCLIENT'
Example of a test API generated:
''' // when: Response response = webTarget .path("/users") .queryParam("limit", "10") .queryParam("offset", "20") .queryParam("filter", "email") .queryParam("sort", "name") .queryParam("search", "55") .queryParam("age", "99") .queryParam("name", "Denis.Stepanov") .queryParam("email", "[email protected]") .request() .method("GET"); String responseAsString = response.readEntity(String.class); // then: assertThat(response.getStatus()).isEqualTo(200); // and: DocumentContext parsedJson = JsonPath.parse(responseAsString); assertThatJson(parsedJson).field("['property1']").isEqualTo("a"); '''
If you’re using asynchronous communication on the server side (your controllers are returning
Callable
, DeferredResult
etc. then inside your contract you have to provide in the response
section a async()
method. Example:
org.springframework.cloud.contract.spec.Contract.make { request { method GET() url '/get' } response { status 200 body 'Passed' async() } }
Spring Cloud Contract supports context paths.
Important | |
---|---|
The only thing that changes in order to fully support context paths is the switch on the PRODUCER side. The autogenerated tests need to be using the EXPLICIT mode. |
The consumer side remains untouched, in order for the generated test to pass you have to switch the EXPLICIT mode.
Maven.
<plugin> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-contract-maven-plugin</artifactId> <version>${spring-cloud-contract.version}</version> <extensions>true</extensions> <configuration> <testMode>EXPLICIT</testMode> </configuration> </plugin>
Gradle.
contracts {
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 com.jayway.restassured.RestAssured; import org.junit.Before; import org.springframework.boot.context.embedded.LocalServerPort; import org.springframework.boot.test.context.SpringBootTest; @SpringBootTest(classes = ContextPathTestingBaseClass.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT) class ContextPathTestingBaseClass { @LocalServerPort int port; @Before public void setup() { RestAssured.baseURI = "http://localhost"; RestAssured.port = this.port; } }
That way all:
/my-context-path/url
)/my-context-path/url
)The DSL for messaging looks a little bit different than the one that focuses on HTTP.
The 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.
The 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.
In 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' ]) } }
It’s possible to define multiple contracts in one file. An example of such a contract can look like this
import org.springframework.cloud.contract.spec.Contract [ Contract.make { name("should post a user") request { method 'POST' url('/users/1') } response { status 200 } }, Contract.make { request { method 'POST' url('/users/2') } response { status 200 } } ]
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 this
should post a user.json 1_WithList.json
As 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).
Tip | |
---|---|
As you can see it’s much better if you name your contracts since then your tests are far more meaningful. |
It 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:
The full example can be found here.
Below 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: $(ProducerUtils.ok())] * ) * } * </pre> * * That way it's in the implementation that we decide what value we will pass to the consumer * and which one to the producer. */ public static ServerDslProperty ok() { // this example is not the best one and // theoretically you could just pass the regex instead of `ServerDslProperty` but // it's just to show some new tricks :) return new ServerDslProperty( PatternUtils.ok(), "OK"); } } //end::impl[]
In order for the plugins and IDE to be able to reference the common JAR classes you need to pass the dependency to your project.
First add the common jar dependency as a test dependency. That way since your contracts files are available at test resources path, automatically the common jar classes will be visible in your Groovy files.
Maven.
<dependency> <groupId>com.example</groupId> <artifactId>beer-common</artifactId> <version>${project.version}</version> <scope>test</scope> </dependency>
Gradle.
testCompile("com.example:beer-common:0.0.1-SNAPSHOT")
Now 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>
Gradle.
classpath "com.example:beer-common:0.0.1-SNAPSHOT"
Now 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()) } } }
There 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).
Let’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: bar
Thanks to the interface
package org.springframework.cloud.contract.spec /** * Converter to be used to convert FROM {@link File} TO {@link Contract} * and from {@link Contract} to {@code T} * * @param <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.
Important | |
---|---|
Once you create your implementation you have to create a |
Example of a spring.factories
file
# Converters org.springframework.cloud.contract.spec.ContractConverter=\ org.springframework.cloud.contract.verifier.converter.YamlContractConverter
and the YAML implementation
package org.springframework.cloud.contract.verifier.converter import java.nio.file.Files import groovy.transform.CompileStatic import org.springframework.cloud.contract.spec.Contract import org.springframework.cloud.contract.spec.ContractConverter import org.springframework.cloud.contract.spec.internal.Headers import org.yaml.snakeyaml.Yaml /** * Simple converter from and to a {@link YamlContract} to a collection of {@link Contract} */ @CompileStatic class YamlContractConverter implements ContractConverter<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 } } }
Spring 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.
We 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" } } }
On 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>
Gradle.
classpath "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" } } }
On 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>
Gradle.
testCompile "org.springframework.cloud:spring-cloud-contract-spec-pact" testCompile 'au.com.dius:pact-jvm-model:2.4.18'
If 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 interface
package org.springframework.cloud.contract.verifier.builder import org.springframework.cloud.contract.verifier.config.ContractVerifierConfigProperties import org.springframework.cloud.contract.verifier.file.ContractMetadata /** * Builds a single test. * * @since 1.1.0 */ interface SingleTestGenerator { /** * Creates contents of a single test class in which all test scenarios from * the contract metadata should be placed. * * @param properties - properties passed to the plugin * @param listOfFiles - list of parsed contracts with additional metadata * @param className - the name of the generated test class * @param classPackage - the name of the package in which the test class should be stored * @param includedDirectoryRelativePath - relative path to the included directory * @return contents of a single test class */ String buildClass(ContractVerifierConfigProperties properties, Collection<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.MyGenerator
If 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.DslToWireMockClientConverter
The default implementation is the WireMock stub generation.
Tip | |
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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! |
If 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 boolean isAccepted(File file) { return file.name.endsWith(".json") } }
and just register it in your spring.factories
file
org.springframework.cloud.contract.stubrunner.HttpServerStub=\ org.springframework.cloud.contract.stubrunner.provider.moco.MocoHttpServerStub
that way you’ll be able to run stubs using Moco.
Important | |
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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. |
You can customize the way your stubs are downloaded. It’s enough to create an
implementation of the StubDownloaderBuilder
package 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.CustomStubDownloaderBuilder
that way you’ll be able to pick a folder with the source of your stubs.
Important | |
---|---|
If you don’t provide any implementation then the default one will be picked.
If you provide |
Modules giving you the possibility to use WireMock with different servers by using the "ambient" server embedded in a Spring Boot application. Check out the samples for more details.
Important | |
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The Spring Cloud Release Train BOM imports |
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.
If 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!"); } }
Note | |
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Actually WireMock always loads mappings from
|
WireMock can read response bodies from files on the classpath or file
system. In that case you will see in the JSON DSL that the response
has a "bodyFileName" instead of a (literal) "body". The files are
resolved relative to a root directory 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.
Note | |
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when you configure the |
For 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.
WireMock allows you to stub a "secure" server with an "https" URL protocol. If your application wants to contact that stub server in an integration test, then it will find that the SSL certificates are not valid (it’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.
Spring 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.
Spring 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" } } }
Note | |
---|---|
You can use either the |
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")
.
Another thing that can be generated with Spring RestDocs is the Spring Cloud Contract DSL file and documentation. If you combine that with Spring Cloud WireMock then you’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.
Tip | |
---|---|
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
).
Here you can find interesting links related to Spring Cloud Contract Verifier: