Advanced HTTP Mocking with WireMock

Video Recording: https://youtu.be/x3MvZ8DFrpE

Create HTTP mocks with WireMock’s REST API from any language for deterministic testing and development. Don’t have mocks yet? No worries. You can record live traffic with WireMock that can be played back. Testing apps that rely on APIs can be painful, flaky and complicated because more than likely, the APIs you rely on are out of your control. It’s time to take control back.

During this talk, you’ll learn how to do the following:

* Record and playback network traffic.

* Programmatically setup mocks via the REST API with cURL, Node.js and Java.

* Simulate error scenarios & latency.

* Verify HTTP calls were made the expected number of times and with expected content.

* Simulate stateful behavior using “scenario” mappings (same endpoint, different results).

Bonuses:

* WireMock is FREE and OPEN SOURCE!

* All of WireMock’s features are accessible via its REST (JSON) interface and its Java API.

* There is a WireMockRule for Java JUnit tests.

* WireMock can run as an embedded HTTP server on an Android device. (with a few config tweaks)

Transcript

1. ADVANCED HTTP MOCKING WITH WIREMOCK Sam Edwards - @HandstandSam
2. @HandstandSam #DevFestDC Why Mock HTTP?
3. @HandstandSam #DevFestDC Why Mock HTTP? • Speed
4. @HandstandSam #DevFestDC Why Mock HTTP? • Speed • Avoid Rate Limits
5. @HandstandSam #DevFestDC Why Mock HTTP? • Speed • Avoid Rate Limits • Avoid Modifying State
6. @HandstandSam #DevFestDC Why Mock HTTP? • Speed • Avoid Rate Limits • Avoid Modifying State • Edge Cases
7. @HandstandSam #DevFestDC Why Mock HTTP? • Speed • Avoid Rate Limits • Avoid Modifying State • Edge Cases • Error Scenarios
8. @HandstandSam #DevFestDC Why Mock HTTP? • Speed • Avoid Rate Limits • Avoid Modifying State • Edge Cases • Error Scenarios • Deterministic
9. @HandstandSam #DevFestDC Why Mock HTTP? • Speed • Avoid Rate Limits • Avoid Modifying State • Edge Cases • Error Scenarios • Deterministic • Testing and TDD
10. @HandstandSam #DevFestDC Mock What and Where?
11. @HandstandSam #DevFestDC What and Where to Mock? Client (Web/Mobile) HTTP Service
12. @HandstandSam #DevFestDC What and Where to Mock? Client (Web/Mobile)
13. @HandstandSam #DevFestDC What and Where to Mock? Client (Web/Mobile) HTTP Service Backend Services
14. @HandstandSam #DevFestDC What and Where to Mock? Client (Web/Mobile) HTTP Service
15. @HandstandSam #DevFestDC What and Where to Mock? Client (Web/Mobile) HTTP Service Backend Services 3rd Party Services
16. @HandstandSam #DevFestDC What and Where to Mock? Client (Web/Mobile) HTTP Service Backend Services
17. @HandstandSam #DevFestDC What is WireMock?
18. @HandstandSam #DevFestDC Open Source, Started in 2011 by Tom Akehurst
19. @HandstandSam #DevFestDC Running WireMock
20. @HandstandSam #DevFestDC Open Source Tool for Mocking HTTP Akehurst.
21. @HandstandSam #DevFestDC Running WireMock • Download Standalone JAR from Maven Central • java -jar wiremock-standalone-2.6.0.jar • http://localhost:8080/__admin/ • --port • --https-port
22. @HandstandSam #DevFestDC Proxying, Recording and Playback
23. @HandstandSam #DevFestDC --proxy-all • --proxy-all http://wiremock.org Client (Web/Mobile) http://wiremock.org
24. @HandstandSam #DevFestDC --verbose • See all traffic going through WireMock.
25. @HandstandSam #DevFestDC --record-mappings • java -jar wiremock-standalone-2.6.0.jar --proxy-all http://wiremock.org --record-mappings • Record all traffic to file-based WireMock mappings. Client (Web/Mobile) http://wiremock.org /__files /mappings
26. @HandstandSam #DevFestDC Playback • java -jar wiremock-standalone-2.6.0.jar • Playback traffic to file-based WireMock mappings. Client (Web/Mobile) /__files /mappings
27. @HandstandSam #DevFestDC • Before & After • curl http://localhost:8080 Manipulating Files Client (Web/Mobile) /__files /mappings
28. @HandstandSam #DevFestDC • http://localhost:8080/__admin/ Viewing Mappings /__files /mappings
29. @HandstandSam #DevFestDC Language Agnostic Stubbing via REST API
30. @HandstandSam #DevFestDC Stubbing via REST API - String Body curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "urlPath": "/hello" }, "response": { "status": 200, "body": "Hello world!", "headers": { "Content-Type": "text/plain" } } }' \ 'http://localhost:8080/__admin/mappings'
31. @HandstandSam #DevFestDC Stubbing via REST API - JSON Response curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "url": "/json" }, "response": { "status": 200, "jsonBody": { "numbers": [1, 2, 3] }, "headers": { "Content-Type": "application/json" } } }' \ 'http://localhost:8080/__admin/mappings'
32. @HandstandSam #DevFestDC Stubbing via REST API - Binary Response curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "url": "/binary" }, "response": { "status": 200, "base64Body" : "WUVTIElOREVFRCE=" } }' \ 'http://localhost:8080/__admin/mappings'
33. @HandstandSam #DevFestDC Complex Stubbing
34. @HandstandSam #DevFestDC HTTP Method Stubbing • ANY • GET • POST • PUT • DELETE • etc....
35. @HandstandSam #DevFestDC URL Pattern Stub curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "urlPathPattern": "/.*/profile$" }, "response": { "status": 200, "body": "User profile goes here.", "headers": { "Content-Type": "text/plain" } } }' \ 'http://localhost:8080/__admin/mappings'
36. @HandstandSam #DevFestDC Query Parameter Stub curl --data '{ "request": { "method": "GET", "urlPath": "/query", "queryParameters":{ "q": { "equalTo": "wiremock" } } }, "response": { "status": 200, "body": "<html><body><h3>It looks like you were searching for WireMock :-) Try <a href=\"http://wiremock.org\">http://wiremock.org</a></h3></body></html>" } }' \ 'http://localhost:8080/__admin/mappings'
37. @HandstandSam #DevFestDC Header Matching Stub curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "urlPath": "/endpoint", "headers" : { "Accept" : { "contains" : "application/json;v=2" } } }, "response": { "status": 200, "jsonBody": { "version": 2 }, "headers": { "Content-Type": "application/json" } } }' \ 'http://localhost:8080/__admin/mappings'
38. @HandstandSam #DevFestDC Header Matching - Miss curl --header 'Accept: application/json;v=1' \ 'http://localhost:8080/endpoint'
39. @HandstandSam #DevFestDC Header Matching - Match curl --header 'Accept: application/json;v=2' \ 'http://localhost:8080/endpoint'
40. @HandstandSam #DevFestDC Request Body Matching curl --verbose \ -X POST \ --data '{ "request": { "method": "POST", "urlPath": "/worldseries", "bodyPatterns" : [ { "contains" : "Orioles" } ] }, "response": { "status": 200, "body": "Orioles win the 2017 World Series!!!" } }' \ 'http://localhost:8080/__admin/mappings'
41. @HandstandSam #DevFestDC Request Body Matching Requests curl --data '{ "team": "Orioles", "score": 10 }' \ 'http://localhost:8080/worldseries'
42. @HandstandSam #DevFestDC JSON Body Matching Stub curl --verbose \ -X POST \ --data '{ "request": { "method": "POST", "urlPath": "/score", "bodyPatterns" : [ { "equalToJson" : "{ \"score\": 10, \"team\": \"Orioles\" }" } ] }, "response": { "status": 200, "body": "Orioles win the 2018 World Series!!!" } }' \ 'http://localhost:8080/__admin/mappings'
43. @HandstandSam #DevFestDC JSON Body Matching Requests curl --data '{ "team": "Orioles", "score": 10 }' \ 'http://localhost:8080/score' curl --data '{ "score": 10, "team": "Orioles" }' \ 'http://localhost:8080/score' curl --data '{ "score": 1, "team": "Red Sox" }' \ 'http://localhost:8080/score'
44. @HandstandSam #DevFestDC Stubbing via REST API - “Catch All” for Unmatched curl --verbose \ -X POST \ --data '{ "priority":10, "request": { "method": "ANY", "urlPattern": ".*" }, "response": { "status": 404, "jsonBody": {"status":"Error","message":"Endpoint not found"}, "headers": { "Content-Type": "application/json" } } }' \ 'http://localhost:8080/__admin/mappings'
45. @HandstandSam #DevFestDC Obtaining a Stub Mapping ID Response from WireMock: { "id" : "4d37cd0d-53dc-46d6-809d-9de83894e167", "request" : { "url" : "/hello", "method" : "GET" }, "response" : { "status" : 200, "body" : "Hello world!", "headers" : { "Content-Type" : "text/plain" } }, "uuid" : "4d37cd0d-53dc-46d6-809d-9de83894e167" }
46. @HandstandSam #DevFestDC Editing Stubs via REST API curl --verbose \ -X PUT \ --data '{ "request": { "method": "GET", "url": "/hello" }, "response": { "status": 200, "body": "Hello world!", "headers": { "Content-Type": "text/plain" } } }' \ 'http://localhost:8080/__admin/mappings/4d37cd0d-53dc-46d6-809d-9de83894e167'
47. @HandstandSam #DevFestDC Deleting Stubs via REST API curl --verbose \ -X DELETE \ 'http://localhost:8080/__admin/mappings/4d37cd0d-53dc-46d6-809d-9de83894e167'
48. @HandstandSam #DevFestDC https://chrome.google.com/webstore/detail/wiremock-extension/ikiaofdpbmofgmlhajfnhdjelkleljbl
49. @HandstandSam #DevFestDC Resetting WireMock Server curl --verbose \ -X POST \ 'http://localhost:8080/__admin/reset'
50. @HandstandSam #DevFestDC Simulating Errors and Latency
51. @HandstandSam #DevFestDC Pre-Defined Fault Types • EMPTY_RESPONSE ◦ Return a completely empty response. • MALFORMED_RESPONSE_CHUNK ◦ Send an OK status header, then garbage, then close the connection. • RANDOM_DATA_THEN_CLOSE ◦ Send garbage then close the connection.
52. @HandstandSam #DevFestDC Simulating Faults curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "url": "/fault" }, "response": { "fault": "MALFORMED_RESPONSE_CHUNK" } }' \ 'http://localhost:8080/__admin/mappings'
53. @HandstandSam #DevFestDC Stub Specific Fixed Delay curl --verbose \ -X POST \ --data '{ "request": { "method": "GET", "url": "/delayed" }, "response": { "status": 200, "body": "Better late than never!", "fixedDelayMilliseconds": 2000 } }' \ 'http://localhost:8080/__admin/mappings'
54. @HandstandSam #DevFestDC Global Random Delay (Can be set specifically as well) curl --verbose \ -X POST \ --data '{ "delayDistribution": { "type": "uniform", "lower": 0, "upper": 5000 } }' \ 'http://localhost:8080/__admin/settings'
55. @HandstandSam #DevFestDC Verifying Networking Calls
56. @HandstandSam #DevFestDC Verifying Network Calls curl --verbose \ -X POST \ --data '{ "method": "GET", "url": "/delayed" }' \ 'http://localhost:8080/__admin/requests/count'
57. @HandstandSam #DevFestDC Full Journal of Network Requests curl --verbose \ -X GET \ 'http://localhost:8080/__admin/requests'
58. @HandstandSam #DevFestDC Stateful Behavior with Scenarios
59. @HandstandSam #DevFestDC Stateful Behavior with Scenarios Grocery List Scenario GET /items “Started” 1. Bread GET /items “One Item” 1. Bread 2. Milk GET /items “Two Items”
60. @HandstandSam #DevFestDC Grocery List Scenario - No Items (“Started”) curl --verbose \ -X POST \ --data '{ "scenarioName": "Grocery List", "requiredScenarioState": "Started", "newScenarioState": "One Item", "request": { "method": "GET", "url": "/items" }, "response": { "status": 200, "jsonBody" : [] } }' \ 'http://localhost:8080/__admin/mappings'
61. @HandstandSam #DevFestDC Grocery List Scenario - No Items (“One Item”) curl --verbose \ -X POST \ --data '{ "scenarioName": "Grocery List", "requiredScenarioState": "One Item", "newScenarioState": "Two Items", "request": { "method": "GET", "url": "/items" }, "response": { "status": 200, "jsonBody" : ["Milk"] } }' \ 'http://localhost:8080/__admin/mappings'
62. @HandstandSam #DevFestDC Grocery List Scenario - No Items (“One Item”) curl --verbose \ -X POST \ --data '{ "scenarioName": "Grocery List", "requiredScenarioState": "Two Items", "newScenarioState": "Started", "request": { "method": "GET", "url": "/items" }, "response": { "status": 200, "jsonBody" : ["Milk", "Bread"] } }' \ 'http://localhost:8080/__admin/mappings'
63. @HandstandSam #DevFestDC Resetting WireMock Scenarios curl --verbose \ -X POST \ 'http://localhost:8080/__admin/scenarios/reset'
64. @HandstandSam #DevFestDC What Kind of Stubbing Should I Use? File Based vs. Programmatic
65. @HandstandSam #DevFestDC File-Based Stubbing Great for: • Recording • Understandability • Sharing Not the best for: • Advanced usage • Maintainability
66. @HandstandSam #DevFestDC Programmatic Stubbing Great for: • Automated Tests • Complex Mocks • Numerous Mocks Not the best for: • Non-developers • Simple use cases
67. @HandstandSam #DevFestDC Language Specific Wrapper Libraries • Java - https://github.com/tomakehurst/wiremock • Ruby - https://github.com/cheezy/service_mock • Closure - https://github.com/alexanderjamesking/clj-wiremock • PHP - https://github.com/rowanhill/wiremock-php • Groovy - https://github.com/tomjankes/wiremock-groovy • Node - https://github.com/jlidder/jswiremock
68. @HandstandSam #DevFestDC Usage in Java & JUnit
69. @HandstandSam #DevFestDC Programmatic Usage in Java for a Remote Server
70. @HandstandSam #DevFestDC Programmatic Usage in Java for a Remote Server
71. @HandstandSam #DevFestDC WireMock Syntax in Java { "request": { "method": "GET", "urlPath": "/categories" }, "response": { "status": 200, "body": "[]" } } stubFor(get(urlPathEqualTo("/categories")).willReturn(aResponse().withStatus(200).withBody("[]")));
72. @HandstandSam #DevFestDC WireMock on Android
73. @HandstandSam #DevFestDC
74. @HandstandSam #DevFestDC WireMock 2.x on Android - Making it Work Hurdles: • Java 7 Compatibility (Jetty 9.2.x) • Apache HTTP Client
75. @HandstandSam #DevFestDC WireMock on Android - Dependencies dependencies { compile("com.github.tomakehurst:wiremock:2.6.0") { exclude group: 'org.apache.httpcomponents', module: 'httpclient' exclude group: 'org.json', module: 'json' exclude group: 'org.ow2.asm', module: 'asm' } compile 'org.apache.httpcomponents:httpclient-android:4.3.5.1' }
76. @HandstandSam #DevFestDC
77. @HandstandSam #DevFestDC
78. @HandstandSam #DevFestDC WireMock on Android - Project Config Recommended, but not required: android { defaultConfig { minSdkVersion 21 multiDexEnabled true } }
79. @HandstandSam #DevFestDC BONUS DEMO: Usage From Android
80. @HandstandSam #DevFestDC Thanks!