Droidcon NYC 2017 - Advanced HTTP Mocking with WireMock

Transcript

1. ADVANCED HTTP MOCKING
   WITH WIREMOCK
   Sam Edwards - @HandstandSam
   

   View Slide

2. @HandstandSam
   #DCNYC17
   WireMock runs as
   an HTTP Server.
   

   View Slide

3. @HandstandSam
   #DCNYC17
   Normally
   Android App
   HTTP
   Web Service
   remotehost.com
   

   View Slide

4. @HandstandSam
   #DCNYC17
   With WireMock
   Android App
   HTTP
   localhost:8080
   remotehost:8080
   

   View Slide

5. @HandstandSam
   #DCNYC17
   Android App HTTP
   In App
   

   View Slide

6. @HandstandSam
   #DCNYC17
   Android App HTTP
   On Device
   In App
   

   View Slide

7. @HandstandSam
   #DCNYC17
   Android App HTTP
   On Device
   In App
   On Laptop
   

   View Slide

8. @HandstandSam
   #DCNYC17
   Android App HTTP
   On Device
   In App
   On Laptop
   Remote Server
   

   View Slide

9. @HandstandSam
   #DCNYC17
   Android App HTTP
   On Device
   In App
   On Laptop
   Remote Server
   localhost:8080
   

   View Slide

10. @HandstandSam
    #DCNYC17
    Android App HTTP
    On Device
    In App
    On Laptop
    Remote Server
    remotehost:8080
    

    View Slide

11. @HandstandSam
    #DCNYC17
    Started in 2011 by Tom Akehurst, Open Source, Apache 2.0
    

    View Slide

12. @HandstandSam
    #DCNYC17
    Presented at GTAC in November 2014 by Michael Bailey
    

    View Slide

13. @HandstandSam
    #DCNYC17
    Official Android Compatibility in January 2016
    

    View Slide

14. @HandstandSam
    #DCNYC17
    Droidcon NYC 2016
    

    View Slide

15. @HandstandSam
    #DCNYC17
    

    View Slide

16. @HandstandSam
    #DCNYC17
    Continuous Integration & Cloud-Based Testing
    etc…
    

    View Slide

17. @HandstandSam
    #DCNYC17
    Deterministic HTTP == More Reliable Tests
    Not All Passing 100% Passed
    

    View Slide

18. @HandstandSam
    #DCNYC17
    Why Mock HTTP Calls?
    • Determinism & Reliability
    • Avoid Rate Limits and Server Costs
    • Avoid Modifying State
    • Edge Cases & Error Scenarios
    • Speed
    

    View Slide

19. @HandstandSam
    #DCNYC17
    Why Mock the HTTP Server?
    • Exercises your full networking stack.
    • Knowledge of the app’s inner-workings are not needed.
    • Swap your HTTP implementation without issues.
    • Use recorded HTTP responses to create representative test cases.
    • Test that your code survives in situations like 500 errors or slow-loading
    responses.
    

    View Slide

20. @HandstandSam
    #DCNYC17
    When should I use HTTP Mocking?
    • Android Tests!
    • Mock Flavor of App
    • Not in your normal Android builds
    

    View Slide

21. @HandstandSam
    #DCNYC17
    public class ErrorScenariosTest {
    @Rule
    public ActivityTestRule mActivityTestRule
    = new ActivityTestRule<>(HomeActivity.class);
    @Test
    public void http500ErrorTest() {
    stubFor(get(urlEqualTo("/category/Nintendo/items"))
    .willReturn(aResponse().withStatus(500)));
    onView(allOf(withId(R.id.categories), isDisplayed()))
    .perform(actionOnItemAtPosition(0, click()));
    onView(withText("Networking Error")).check(matches(isDisplayed()));
    }
    }
    

    View Slide

22. @HandstandSam
    #DCNYC17
    public class ErrorScenariosTest {
    @Rule
    public ActivityTestRule mActivityTestRule
    = new ActivityTestRule<>(HomeActivity.class);
    @Test
    public void http500ErrorTest() {
    stubFor(get(urlEqualTo("/category/Nintendo/items"))
    .willReturn(aResponse().withStatus(500)));
    onView(allOf(withId(R.id.categories), isDisplayed()))
    .perform(actionOnItemAtPosition(0, click()));
    onView(withText("Networking Error")).check(matches(isDisplayed()));
    }
    }
    

    View Slide

23. @HandstandSam
    #DCNYC17
    public class ErrorScenariosTest {
    @Rule
    public ActivityTestRule mActivityTestRule
    = new ActivityTestRule<>(HomeActivity.class);
    @Test
    public void http500ErrorTest() {
    stubFor(get(urlEqualTo("/category/Nintendo/items"))
    .willReturn(aResponse().withStatus(500)));
    onView(allOf(withId(R.id.categories), isDisplayed()))
    .perform(actionOnItemAtPosition(0, click()));
    onView(withText("Networking Error")).check(matches(isDisplayed()));
    }
    }
    

    View Slide

24. @HandstandSam
    #DCNYC17
    

    View Slide

25. @HandstandSam
    #DCNYC17
    WHAT IS WIREMOCK?
    

    View Slide

26. @HandstandSam
    #DCNYC17
    Mapping
    GET - /hello - should return “Hello!”
    

    View Slide

27. @HandstandSam
    #DCNYC17
    WireMock Mappings
    HTTP GET - /hello - “Hello!”
    POST - /hi “hi.”
    Mappings
    ANY - /goodbye “Goodbye.”
    File-based REST API JVM
    

    View Slide

28. @HandstandSam
    #DCNYC17
    WireMock Mapping
    {
    "request": {
    "method": "GET",
    "urlPath": "/hello"
    },
    "response": {
    "status": 200,
    “body": “Hello!”,
    "headers": {
    "Content-Type": "text/plain"
    }
    }
    }
    

    View Slide

29. @HandstandSam
    #DCNYC17
    Recording
    

    View Slide

30. @HandstandSam
    #DCNYC17
    Proxying
    Android App Web Service
    https://shopping-app.s3.amazonaws.com
    

    View Slide

31. @HandstandSam
    #DCNYC17
    Record File-based Mappings to Disk while Proxying
    Android App Web Service
    /__files /mappings
    https://shopping-app.s3.amazonaws.com
    

    View Slide

32. @HandstandSam
    #DCNYC17
    Record File-based Mappings to Disk
    Programmatic Java
    WireMockServer wireMockServer = new WireMockServer(wireMockConfig().withRootDirectory(getRootDirectory()));
    wireMockServer.enableRecordMappings(new SingleRootFileSource(getMappingDirectory()),
    new SingleRootFileSource(getFileDirectory()));
    wireMockServer.stubFor(any(urlMatching(“.*”)).willReturn(aResponse()
    .proxiedFrom(“https://shopping-app.s3.amazonaws.com”)));
    wireMockServer.start();
    Command Line
    java -jar wiremock-standalone-2.8.0.jar \

    --proxy-all https://shopping-app.s3.amazonaws.com \

    --record-mappings
    

    View Slide

33. @HandstandSam
    #DCNYC17
    Demo:
    Android Recording
    

    View Slide

34. @HandstandSam
    #DCNYC17
    File-Based Recording & Playback on Android
    • Caveats:
    • Must configure to use External Storage/SD Card for __files and mappings
    • Recommendation (getting started):
    • Use Emulator & Run WireMock on Laptop
    • Connect Emulator to http://10.0.2.2:8080
    

    View Slide

35. @HandstandSam
    #DCNYC17
    Playback
    of File-Based Mappings
    on Android
    

    View Slide

36. @HandstandSam
    #DCNYC17
    Playback File-based Mappings
    Android App
    /__files /mappings
    HTTP
    

    View Slide

37. @HandstandSam
    #DCNYC17
    Playback File-based Mappings from Disk
    Programmatic Java
    WireMockServer wireMockServer = new WireMockServer(wireMockConfig().withRootDirectory(getRootDirectory()));
    wireMockServer.start();
    Command Line
    java -jar wiremock-standalone-2.8.0.jar
    

    View Slide

38. @HandstandSam
    #DCNYC17
    Viewing Mappings
    • http://localhost:8080/__admin/
    /__files /mappings
    

    View Slide

39. @HandstandSam
    #DCNYC17
    Demo:
    Android Playback
    

    View Slide

40. @HandstandSam
    #DCNYC17
    Stubbing
    

    View Slide

41. @HandstandSam
    #DCNYC17
    Terminology
    “Stubbing” is the act of creating a “Mapping”
    programmatically
    

    View Slide

42. @HandstandSam
    #DCNYC17
    Stubbing Options
    ● File-based
    ● JVM
    ● REST API
    

    View Slide

43. @HandstandSam
    #DCNYC17
    Programmatic Stubbing via Java API
    stubFor(get(urlEqualTo(“/hello"))
    .willReturn(aResponse()
    .withHeader("Content-Type", "text/plain")
    .withBody("Hello world!")));
    

    View Slide

44. @HandstandSam
    #DCNYC17
    Programmatic Stubbing via Java API
    stubFor(get(urlEqualTo(“/hello"))
    .willReturn(aResponse()
    .withHeader("Content-Type", "text/plain")
    .withBody("Hello world!")));
    

    View Slide

45. @HandstandSam
    #DCNYC17
    Programmatic Stubbing via Java API
    stubFor(get(urlEqualTo(“/hello"))
    .willReturn(aResponse()
    .withHeader("Content-Type", "text/plain")
    .withBody("Hello world!")));
    

    View Slide

46. @HandstandSam
    #DCNYC17
    Programmatic Stubbing via Java API
    stubFor(get(urlEqualTo(“/hello"))
    .willReturn(aResponse()
    .withHeader("Content-Type", "text/plain")
    .withBody("Hello world!")));
    

    View Slide

47. @HandstandSam
    #DCNYC17
    Programmatic Stubbing via Java API
    stubFor(get(urlEqualTo(“/hello"))
    .willReturn(aResponse()
    .withHeader("Content-Type", "text/plain")
    .withBody("Hello world!")));
    

    View Slide

48. @HandstandSam
    #DCNYC17
    WireMock Mapping
    {
    "request": {
    "method": "GET",
    "urlPath": "/hello"
    },
    "response": {
    "status": 200,
    “body": “Hello!”,
    "headers": {
    "Content-Type": "text/plain"
    }
    }
    }
    

    View Slide

49. @HandstandSam
    #DCNYC17
    Stubbing Options
    ● File-based
    ● JVM
    ● REST API
    

    View Slide

50. @HandstandSam
    #DCNYC17
    Running WireMock Standalone JAR
    • Download Standalone JAR from Maven Central
    • java -jar wiremock-standalone-2.8.0.jar
    • --port
    • --https-port
    • http://localhost:8080/__admin/
    

    View Slide

51. @HandstandSam
    #DCNYC17
    Demo:
    Language Agnostic Stubbing
    via REST API
    

    View Slide

52. @HandstandSam
    #DCNYC17
    Running WireMock as a Proxy
    java -jar wiremock-standalone-2.8.0.jar \

    --proxy-all https://shopping-app.s3.amazonaws.com
    

    View Slide

53. @HandstandSam
    #DCNYC17
    Programmatic Stubbing via REST API
    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'
    

    View Slide

54. @HandstandSam
    #DCNYC17
    Stubbing via REST API - String Body
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "url": "/category/Nintendo/items"
    },
    "response": {
    "status": 200,
    "body": "[{\"label\": \"?\"}]"
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

55. @HandstandSam
    #DCNYC17
    Stubbing via REST API - JSON Response
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "url": "/category/Nintendo/items"
    },
    "response": {
    "jsonBody": [{
    "image": "https://shopping-app.s3.amazonaws.com/droidcon-nyc/droidcon-nyc.png",
    "label": "Droidcon NYC"
    }]
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

56. @HandstandSam
    #DCNYC17
    Stubbing via REST API - Binary Response
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "url": "/category/Nintendo/items"
    },
    "response": {
    "base64Body": "W3sibGFiZWwiOiAiQmFzZTY0IEVuY29kZWQifV0="
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

57. @HandstandSam
    #DCNYC17
    Stubbing via REST API - 500 Error Response
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "url": "/category/Nintendo/items"
    },
    "response": {
    "status": 500
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

58. @HandstandSam
    #DCNYC17
    https://chrome.google.com/webstore/detail/wiremock-extension/ikiaofdpbmofgmlhajfnhdjelkleljbl
    

    View Slide

59. @HandstandSam
    #DCNYC17
    Complex Stubbing
    

    View Slide

60. @HandstandSam
    #DCNYC17
    URL Pattern Stub
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "urlPathPattern": "/category/.*/items$"
    },
    "response": {
    "jsonBody": [{
    "image": "https://shopping-app.s3.amazonaws.com/droidcon-nyc/kittens.jpg",
    "label": "Kittens"
    }]
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

61. @HandstandSam
    #DCNYC17
    Query Parameter Stub
    curl --data '{
    "request": {
    "method": "GET",
    "urlPath": "/protected",
    "queryParameters":{
    "password": {
    "equalTo": "password"
    }
    }
    },
    "response": {
    "body": "How did you know that my password was 'password'?"
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

62. @HandstandSam
    #DCNYC17
    Other Complex Stubbing
    • Header Matching (Serve Multiple API Versions)
    • Request Body Matching
    • Equal To
    • Contains
    • JSON Body
    • Doesn’t care about order of JSON elements
    

    View Slide

63. @HandstandSam
    #DCNYC17
    Simulating Errors and
    Latency
    

    View Slide

64. @HandstandSam
    #DCNYC17
    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.
    

    View Slide

65. @HandstandSam
    #DCNYC17
    Simulating Faults
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "url": "/category/Nintendo/items"
    },
    "response": {
    "fault": "MALFORMED_RESPONSE_CHUNK"
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

66. @HandstandSam
    #DCNYC17
    Stub Specific Fixed Delay
    curl --verbose \
    -X POST \
    --data '{
    "request": {
    "method": "GET",
    "url": "/category/Nintendo/items"
    },
    "response": {
    "body": "[{\"label\": \"Better Late Than Never\"}]",
    "fixedDelayMilliseconds": "2000"
    }
    }' \
    'http://localhost:8080/__admin/mappings'
    

    View Slide

67. @HandstandSam
    #DCNYC17
    Delay Types
    • Stub-specific Delays
    • Global Delays
    • Static Delays
    • Random Delays
    

    View Slide

68. @HandstandSam
    #DCNYC17
    Stateful Behavior with
    Scenarios
    

    View Slide

69. @HandstandSam
    #DCNYC17
    1. One
    Stateful Behavior with Scenarios
    Shopping List Scenario States
    GET /items
    Required: “Started”
    New State: “Two Items”
    1. One
    2. Two
    GET /items
    Required: “Two Items”
    New State: “Three Items”
    1. One
    2. Two
    3. Three
    GET /items
    Required: “Three Items”
    New State: “Started”
    

    View Slide

70. @HandstandSam
    #DCNYC17
    Verifying Networking Calls
    

    View Slide

71. @HandstandSam
    #DCNYC17
    Verifying Network Calls (Mockito-like Syntax)
    • Verify Called Once

    

    verify(getRequestedFor(urlEqualTo(“/category/Nintendo/items”)));
    • Verify Called 3 Times

    

    verify(3, getRequestedFor(urlEqualTo(“/category/Nintendo/items”)));
    • Full Request Log

    

    List allServeEvents = wireMockServer.getAllServeEvents();
    

    View Slide

72. @HandstandSam
    #DCNYC17
    Programmatic Resets
    • wireMockServer.resetMappings();
    • wireMockServer.resetScenarios();
    

    View Slide

73. @HandstandSam
    #DCNYC17
    What Kind of Stubbing
    Should I Use?
    File Based vs. Programmatic
    

    View Slide

74. @HandstandSam
    #DCNYC17
    Programmatic Mocks > File-based Mocks
    ● Save time by avoiding time consuming record/playback cycle.
    ● Generate time-sensitive data (yesterday, etc).
    ● Iterate through models to generate multiple ID specific mappings.
    ● Hold a programmatic model of expected results for assertions.
    ● Again, save a LOT of time after a small-ish upfront investment.
    

    View Slide

75. @HandstandSam
    #DCNYC17
    File-based Mocks > Programmatic Mocks
    ● Recording
    ● Getting Started
    ● Simple Cases
    ● Working with Non-Developers
    

    View Slide

76. @HandstandSam
    #DCNYC17
    Android Caveats
    

    View Slide

77. @HandstandSam
    #DCNYC17
    WireMock on Android - Dependencies
    dependencies {
    androidTestCompile(“com.github.tomakehurst:wiremock:2.8.0") {
    exclude group: 'org.apache.httpcomponents', module: 'httpclient'
    exclude group: 'org.json', module: 'json'
    exclude group: 'org.ow2.asm', module: 'asm'
    }
    androidTestCompile 'org.apache.httpcomponents:httpclient-android:4.3.5.1'
    }
    

    View Slide

78. @HandstandSam
    #DCNYC17
    

    View Slide

79. @HandstandSam
    #DCNYC17
    

    View Slide

80. @HandstandSam
    #DCNYC17
    WireMock on Android - Project Config
    Recommended, but not required:
    android {
    defaultConfig {
    minSdkVersion 21
    multiDexEnabled true
    }

    }
    

    View Slide

81. @HandstandSam
    #DCNYC17
    Final Thoughts
    

    View Slide

82. @HandstandSam
    #DCNYC17
    Recommendations
    • Play with WireMock as a desktop/server tool immediately. It’s awesome.
    • Evaluate other libraries. Don’t use WireMock in your app until you’ve looked at other options.
    • Mock Web Server - HTTP Server
    • Mock Web Server + RESTMock - More powerful
    • OkReplay - OkHttp Interceptor + File Based Recording
    • Retrofit - Behavior Delegate
    • Mockito
    • 70,000 methods??? - Multidex and get over it
    

    View Slide

83. @HandstandSam
    #DCNYC17
    Don’t carry a Swiss-Army
    Knife if you only need a
    knife.
    

    View Slide

84. @HandstandSam
    #DCNYC17
    THANKS!
    https://github.com/handstandsam/ShoppingApp
    

    View Slide