Consumer Driven Contracts

Transcript

1. CONSUMER DRIVEN CONTRACTS Boost your confidence with @ordepdev
2. Testing is hard The pyramid is, most of the times, inverted.
3. BUILDING MICROSERVICES WITHOUT BREAKING CONTRACTS IS EVEN HARDER
4. MONOLITHS VS MICROSERVICES MONOLITH build test deploy
5. MONOLITHS VS MICROSERVICES build test deploy build test deploy build test deploy microservices a b c
6. HOW DO WE TEST MICROSERVICES?
7. integration Mocking, Faking, Stubbing, you choose.
8. INTEGRATION TESTS build test deploy We build our own stubs in order to make our tests pass a b
9. end-to-end Those bloated and long to run… The feedback from this slide is already late.
10. END-TO-END-TESTS build test deploy build test deploy build test deploy microservices END-TO-END Hard to write and maintain, slow to execute, and late feedback a b c
11. What is wrong with this? Slow to run Very late feedback Hard to write and maintain Mocked stubs can be different from the reality Leads to passing tests and failing in production
12. What is wrong with this? Slow to run Very late feedback Hard to write and maintain Mocked stubs can be different from the reality Leads to passing tests and failing in production
13. What is wrong with this? Slow to run Very late feedback Hard to write and maintain Mocked stubs can be different from the reality Leads to passing tests and failing in production
14. What is wrong with this? Slow to run Very late feedback Hard to write and maintain Mocked stubs can be different from the reality Leads to passing tests and failing in production
15. What is wrong with this? Slow to run Very late feedback Hard to write and maintain Mocked stubs can be different from the reality Leads to passing tests and failing in production
16. # Check if a person with a given age can drink beer curl -H "Content-Type: application/json" -X POST \ -d ‘{ “age”: 20 }' \ http://some.external.api:8090/check ~ provided by the producer at some point of time REAL LIFE EXAMPLE This snippet was taken from JIRA or some random Slack channel
17. @Test public void check_withValidAge_shouldReturnHttpStatusOk() throws Exception { ResponseEntity<ResponsePayload> response = restTemplate.exchange( RequestEntity .put(URI.create("http://localhost:8080/chekc")) .contentType(MediaType.APPLICATION_JSON_UTF8) .body(new RequestPayload(10)), ResponsePayload.class); assertThat(response.getStatusCode()).isEqualByComparingTo(HttpStatus.OK); } TESTING on the consumer side
18. @Test public void check_withValidAge_shouldReturnHttpStatusOk() throws Exception { ResponseEntity<ResponsePayload> response = restTemplate.exchange( RequestEntity .put(URI.create("http://localhost:8091/items/validate")) .contentType(MediaType.APPLICATION_JSON_UTF8) .body(new RequestPayload(10)), ResponsePayload.class); assertThat(response.getStatusCode()).isEqualByComparingTo(HttpStatus.OK); } check_withValidAge_shouldReturnHttpStatusOk OK TESTING on the consumer side
19. @Test public void check_withValidAge_shouldReturnHttpStatusOk() throws Exception { ResponseEntity<ResponsePayload> response = restTemplate.exchange( RequestEntity .put(URI.create("http://localhost:8080/chekc")) .contentType(MediaType.APPLICATION_JSON_UTF8) .body(new RequestPayload(10)), ResponsePayload.class); assertThat(response.getStatusCode()).isEqualByComparingTo(HttpStatus.OK); } TESTING on the consumer side
20. @Test public void check_withValidAge_shouldReturnHttpStatusOk() throws Exception { ResponseEntity<ResponsePayload> response = restTemplate.exchange( RequestEntity .put(URI.create("http://localhost:8080/chekc")) .contentType(MediaType.APPLICATION_JSON_UTF8) .body(new RequestPayload(10)), ResponsePayload.class); assertThat(response.getStatusCode()).isEqualByComparingTo(HttpStatus.OK); } TESTING on the consumer side
21. @Test public void check_withValidAge_shouldReturnHttpStatusOk() throws Exception { ResponseEntity<ResponsePayload> response = restTemplate.exchange( RequestEntity .put(URI.create("http://localhost:8080/chekc")) .contentType(MediaType.APPLICATION_JSON_UTF8) .body(new RequestPayload(10)), ResponsePayload.class); assertThat(response.getStatusCode()).isEqualByComparingTo(HttpStatus.OK); } TESTING on the consumer side
22. @Test public void check_withValidAge_shouldReturnHttpStatusOk() throws Exception { ResponseEntity<ResponsePayload> response = restTemplate.exchange( RequestEntity .put(URI.create("http://localhost:8080/chekc")) .contentType(MediaType.APPLICATION_JSON_UTF8) .body(new RequestPayload(10)), ResponsePayload.class); assertThat(response.getStatusCode()).isEqualByComparingTo(HttpStatus.OK); } TESTING on the consumer side
23. after deploy…
24. “An integration contract test is a test at the boundary of an external service verifying that it meets the contract expected by a consuming service” Martin Fowler Contract testing?
25. “An integration contract test is a test at the boundary of an external service verifying that it meets the contract expected by a consuming service” Martin Fowler Contract testing?
26. Expectations Contract Testing is all about… Shared between the producer and the consumer.
27. SPRING CLOUD CONTRACT
28. PRODUCER CONSUMER Common repository with contracts
29. PRODUCER CONSUMER Creates a PR with the proposed contracts
30. PRODUCER CONSUMER Review contracts and writes the missing implementation
31. PRODUCER CONSUMER Merge PR with the proposed and validated contracts
32. PRODUCER CONSUMER Contracts JAR gets deployed into Nexus CONSUMER
33. STUBS ALWAYS MATCH SERVER-SIDE IMPLEMENTATION
34. CHANGES ARE IMMEDIATELY VISIBLE ON BOTH SIDES
35. Contract.make { request { method "POST" url "/check" body ([ age: value(regex("[2-9][0-9]")) ]) headers { contentType(applicationJson()) } } response { status 200 body([ status: "OK" ]) headers { contentType(applicationJson()) } } } defining the contract
36. Contract.make { request { method "POST" url "/check" body ([ age: value(regex("[2-9][0-9]")) ]) headers { contentType(applicationJson()) } } response { status 200 body([ status: "OK" ]) headers { contentType(applicationJson()) } } } defining the contract
37. @Test public void validate_validSizeShouldReturnHttpOk() throws Exception { // given: MockMvcRequestSpecification request = given() .header("Content-Type", "application/json") .body("{\"age\":\"20\"}"); // when: ResponseOptions response = given().spec(request) .post("/check"); // 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("['status']").isEqualTo("OK"); } generated tests
38. @Test public void validate_validSizeShouldReturnHttpOk() throws Exception { // given: MockMvcRequestSpecification request = given() .header("Content-Type", "application/json") .body("{\"age\":\"20\"}"); // when: ResponseOptions response = given().spec(request) .post("/check"); // 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("['status']").isEqualTo("OK"); } generated tests
39. @Test public void validate_validSizeShouldReturnHttpOk() throws Exception { // given: MockMvcRequestSpecification request = given() .header("Content-Type", "application/json") .body("{\"age\":\"20\"}"); // when: ResponseOptions response = given().spec(request) .post("/check"); // 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("['status']").isEqualTo("OK"); } generated testS
40. { "request" : { "url" : "/check", "method" : "POST", "headers" : { "Content-Type" : { "matches" : "application/json.*" } }, "bodyPatterns" : [ { "matchesJsonPath" : "$[?(@.['age'] =~ /[2-9][0-9]/)]" } ] }, "response" : { "status" : 200, "body" : "{\"status\":\"OK\"}", "headers" : { "Content-Type" : "application/json" } } } generated stub
41. { "request" : { "url" : "/check", "method" : "POST", "headers" : { "Content-Type" : { "matches" : "application/json.*" } }, "bodyPatterns" : [ { "matchesJsonPath" : "$[?(@.['age'] =~ /[2-9][0-9]/)]" } ] }, "response" : { "status" : 200, "body" : "{\"status\":\"OK\"}", "headers" : { "Content-Type" : "application/json" } } } generated stub
42. CONSUMER TESTING WITH STUBS @RunWith(SpringRunner.class) @SpringBootTest(webEnvironment = WebEnvironment.MOCK) @AutoConfigureStubRunner( workOffline = true, ids = "com.example:beer-api-producer-external:+:stubs:8090" ) public class BeerControllerTest extends AbstractTest { @Test void should_give_me_a_beer_when_im_old_enough() { mockMvc.perform(MockMvcRequestBuilders.post("/beer") .contentType(MediaType.APPLICATION_JSON) .content(json.write(new Person("John Doe", 20)).getJson())) .andExpect(status().isOk()) .andExpect(content().string("THERE YOU GO")); } }
43. CONSUMER TESTING WITH STUBS @RunWith(SpringRunner.class) @SpringBootTest(webEnvironment = WebEnvironment.MOCK) @AutoConfigureStubRunner( workOffline = true, ids = "com.example:beer-api-producer-external:+:stubs:8090" ) public class BeerControllerTest extends AbstractTest { @Test void should_give_me_a_beer_when_im_old_enough() { mockMvc.perform(MockMvcRequestBuilders.post("/beer") .contentType(MediaType.APPLICATION_JSON) .content(json.write(new Person("John Doe", 20)).getJson())) .andExpect(status().isOk()) .andExpect(content().string("THERE YOU GO")); } }
44. A contract needs to speak the truth.
45. How can we verify the truth?
46. Running a test!
47. CONFIDENCE Continuously evolve your codebase without breaking contracts
48. Faster No need to setup end-to-end environments
49. Less Error Prone Verification of Contracts are automatically managed
50. Thank you. @ordepdev
51. CONSUMER DRIVEN CONTRACTS Boost your confidence with @ordepdev