Talk Creating and testing REST and Messaging contracts with Spring Cloud Contract

REST and Messaging solutions do not come with an in-built contract compliance mechanism, which in many ways is a great thing. However, while working with microservice-based systems, it often appears that a practical mechanism that would provide help in shaping and describing REST and Messaging contracts would come in handy. Similarly, creating integration and acceptance tests in such systems presents many challenges.

In this talk, I present Spring Cloud Contract, a contract verification solution, written in big part in Groovy, that allows for both: easily shaping REST and Messaging contracts and verifying if our app adheres to them using automatically generated Spock tests. I will show how, using Spring Cloud Contract, we can quickly generate automatically-tested stubs from simple Groovy DSL scripts. I will talk about the typical usages and script examples, as well as possible problems and ways of handling them.

Transcript

1. Creating and testing REST Creating and testing REST and Messaging contracts and Messaging contracts with Spring Cloud Contract with Spring Cloud Contract @olga_maciaszek Olga Maciaszek-Sharma 27.07.2018
2. Olga Maciaszek-Sharma Olga Maciaszek-Sharma @olga_maciaszek https:/ /github.com/OlgaMaciaszek https:/ /github.com/OlgaMaciaszek @ @olga_maciaszek olga_maciaszek
3. E2E Tests E2E Tests @olga_maciaszek
4. @olga_maciaszek Source: https://testing.googleblog.com/2015/04/just-say-no-to-more-end-to-end-tests.html Test Pyramid Test Pyramid
5. Microservices Microservices @olga_maciaszek
6. Fully Deployed Test Fully Deployed Test Environment Environment @olga_maciaszek Environment per Service Environment per Service One To Rule Them All One To Rule Them All
7. Deployment Deployment Coupling Coupling @olga_maciaszek
8. Failsafe Failsafe vs. vs. Safe To Fail Safe To Fail @olga_maciaszek
9. Circuit Breakers Circuit Breakers @olga_maciaszek
10. How many E2E? How many E2E? @olga_maciaszek
11. Stubbed Environments Stubbed Environments @olga_maciaszek Outdated Stubs Outdated Stubs
12. Contracts Contracts @olga_maciaszek Monitoring Monitoring Alerting Alerting Logging Logging Unit Tests Unit Tests
13. Input A ==> Output B Input A ==> Output B @olga_maciaszek Contracts Contracts
14. Consumer-Driven Contracts Consumer-Driven Contracts https://martinfowler.com/articles/consum erDrivenContracts.html @olga_maciaszek
15. Contract Tests Contract Tests https://martinfowler.com/bliki/ContractTest.html @olga_maciaszek
16. Spring Cloud Contract Spring Cloud Contract https://cloud.spring.io/spring-cloud-contract/ @olga_maciaszek
17. SCC Flow SCC Flow @olga_maciaszek
18. SCC Flow SCC Flow @olga_maciaszek
19. Contracts Contracts package contracts org.springframework.cloud.contract.spec.Contract.make { request { method 'PUT' url '/fraudcheck' body([ "client.id": $(regex('[0-9]{10}')), loanAmount: 99999 ]) headers { contentType('application/json') } } response { status OK() body([ fraudCheckStatus: "FRAUD", "rejection.reason": "Amount too high" ]) headers { contentType('application/json') } } } @olga_maciaszek
20. Contracts Contracts request: method: PUT url: /fraudcheck body: "client.id": 1234567890 loanAmount: 99999 headers: Content-Type: application/json matchers: body: - path: $.['client.id'] type: by_regex value: "[0-9]{10}" response: status: 200 body: fraudCheckStatus: "FRAUD" "rejection.reason": "Amount too high" headers: Content-Type: application/json;charset=UTF-8 @olga_maciaszek
21. SCC Flow SCC Flow @olga_maciaszek
22. Gradle Setup - Producer Gradle Setup - Producer buildscript { repositories { mavenCentral() maven {url 'http://repo.spring.io/release'} } dependencies { classpath("org.springframework.cloud:spring-cloud-contract-gradle } } apply plugin: 'spring-cloud-contract' contracts { targetFramework = 'SPOCK' baseClassForTests = 'com.example.contractsdemo.FraudCheckTestBaseClass' } @olga_maciaszek
23. Contract Tests Contract Tests def validate_shouldMarkClientAsFraud() { given: def request = given() .header('Content-Type', 'application/vnd.fraud.v1+json') .body('{"clientId":"12345678902","loanAmount":99999}') when: def response = given().spec(request).put("/fraudcheck") then: response.statusCode == 200 response.header('Content-Type') == 'application/vnd.fraud.v1+json' and: DocumentContext parsedJson = JsonPath.parse(response.body.asString()) assertTassertThatJson(parsedJson).field("rejectionReason") .isEqualTo("Amount too high") assertThatJson(parsedJson).field("fraudCheckStatus").isEqualTo("FRAUD") } @olga_maciaszek
24. Stubs Stubs { "request": { "url": "/fraudcheck", "method": "PUT", "bodyPatterns": [ { "matchesJsonPath": "$[?(@.loanAmount == 99999)]" }, { "matchesJsonPath": "$[?(@.clientId == '12345678902')]" } ], "headers": { "Content-Type": { "equalTo": "application/vnd.fraud.v1+json" } } }, "response": { "status": 200, "body": "{\"fraudCheckStatus\":\"FRAUD\", \"rejectionReason\":\"Amount too high\"}", "headers": { "Content-Type": "application/vnd.fraud.v1+json" } } } @olga_maciaszek
25. SCC Flow SCC Flow @olga_maciaszek
26. SCC Flow SCC Flow @olga_maciaszek
27. Gradle Setup - Consumer Gradle Setup - Consumer dependencies { testCompile('org.springframework.cloud:spring-cloud-starter-contract-stub-runner') } @olga_maciaszek
28. Using Stubs Using Stubs @RunWith(SpringRunner.class) @SpringBootTest(webEnvironment=WebEnvironment.NONE) @AutoConfigureStubRunner(ids = {"com.example:http-server-dsl:+:stubs:6565"}, stubsMode = StubRunnerProperties.StubsMode.LOCAL) @DirtiesContext public class LoanApplicationServiceTests { ... } @olga_maciaszek @StubRunnerPort
29. Using Stubs Using Stubs 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 stubs-mode: remote @olga_maciaszek @ContextConfiguration(classes = Config, loader = SpringBootContextLoader) @SpringBootTest(properties = [" stubrunner.cloud.enabled=false"]) @AutoConfigureStubRunner @DirtiesContext @ActiveProfiles("test") class StubRunnerConfigurationSpec extends Specification { @Autowired StubFinder stubFinder def 'should start WireMock servers'() { expect: 'WireMocks are running' stubFinder.findStubUrl('org.verifier.stubs', 'loanIssuance') != null }
30. Using Stubs Using Stubs @Rule public StubRunnerRule rule = new StubRunnerRule() .downloadStub("com.example","fraud-service") .stubsMode(StubRunnerProperties.StubsMode.LOCAL) .withStubPerConsumer(true) .withConsumerName("loan-service"); int fraudServicePort = rule.findStubUrl("fraud-service").getPort() @olga_maciaszek
31. Code Demo Code Demo @olga_maciaszek
32. Messaging Contracts Messaging Contracts def contractDsl = Contract.make { label 'some_label' input { messageFrom('inputQueue') messageBody([ bookName: 'foo' ]) messageHeaders { header('sample', 'header') } } outputMessage { sentTo('outputQueue') body([ bookName: 'foo' ]) headers { header('BOOK-NAME', 'foo') } } } @olga_maciaszek
33. Messaging Contract Tests Messaging Contract Tests given: ContractVerifierMessage inputMessage = contractVerifierMessaging.create( '''{"bookName":"foo"}''', ['sample': 'header'] ) when: contractVerifierMessaging.send(inputMessage, 'inputQueue') then: ContractVerifierMessage response = contractVerifierMessaging .receive('outputQueue') assert response != null response.getHeader('BOOK-NAME')?.toString() == 'foo' and: DocumentContext parsedJson = JsonPath.parse(contractVerifierObjectMapper .writeValueAsString(response.payload)) assertThatJson(parsedJson).field("bookName").isEqualTo("foo") @olga_maciaszek
34. Messaging Client-Side Test Messaging Client-Side Test given: messaging.send(new BookReturned('foo'), [sample: 'header'], 'input') when: Message<?> receivedMessage = messaging.receive('outputTest') then: receivedMessage != null assertJsons(receivedMessage.payload) receivedMessage.headers.get('BOOK-NAME') == 'foo' @olga_maciaszek
35. Public API Public API Spring Rest Docs Spring Rest Docs MockMvc Tests -> REST Docs, Stubs, Contracts @olga_maciaszek
36. Public API Public API mvn spring-cloud-contract:run -Dstubs="org.springframework:gs-rest-service" Docs @olga_maciaszek
37. Generate Rest Docs Generate Rest Docs from Contracts from Contracts @olga_maciaszek
38. Contracts Scope Contracts Scope Skip Contracts for non- Skip Contracts for non- essential functionality essential functionality @olga_maciaszek
39. Contracts Scope Contracts Scope Skip multiple values Skip multiple values @olga_maciaszek
40. Skip Multiple Values Skip Multiple Values @olga_maciaszek request { method 'PUT' url '/fraudcheck' body([ "client.id": $(regex('[0-9]{10}')), "client.type" : "INDIVIDUAL" loanAmount: 99999 ]) headers { contentType('application/json') }} request { method 'PUT' url '/fraudcheck' body([ "client.id": $(regex('[0-9]{10}')), "client.type" : "BUSINESS" loanAmount: 99999 ]) headers { contentType('application/json') }}
41. Architecture TDD Architecture TDD @olga_maciaszek
42. Backwards Backwards Compatibility Check Compatibility Check Spring Cloud Pipelines Spring Cloud Pipelines @olga_maciaszek
43. Deferred Updates Deferred Updates @olga_maciaszek
44. No app versioning No app versioning @olga_maciaszek
45. Spring Cloud Contract at Spring Cloud Contract at Devskiller - case study Devskiller - case study blogpost blogpost @olga_maciaszek
46. Demo Code Links Demo Code Links https://github.com/OlgaMaciaszek/contracts-demo- producer https://github.com/OlgaMaciaszek/contracts-demo- consumer @olga_maciaszek
47. https:/ /github.com/OlgaMaciaszek https:/ /github.com/OlgaMaciaszek @ @olga_maciaszek olga_maciaszek Thank you Thank you