Reacting to Change - API Days 2014

Transcript

1. REACTING
   TO CHANGE !
   KYLE FULLER
   

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2. BUILDING better
   API CLIENTS
   

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5. DOZENS
   of APPS
   

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6. HTTP / APIS
   

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7. THERE’S AN API
   

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8. COMPONENTS OF AN
   API CLIENT
   

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9. perform(.RetrieveArticles) { result in
   switch result {
   case .Success(let representor):
   /* We've got some articles */
   case .Error(let error):
   /* We hit an error */
   }
   }
   

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10. FOUNDATION
    

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11. NSURLSession
    OR
    NSURLConnection
    

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12. NSURLRequest
    

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13. NSURLHTTPResponse
    

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14. SIMPLE...
    

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15. HTTP
    SEMANTICS
    

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16. SERIALISATION (JSON)
    

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17. CONVERT to
    VALUE-MODELS
    

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18. struct Article {
    let title:String
    let body:String
    let author:Author
    let image:[NSURL]
    }
    struct Author {
    let name:String
    let twitter:String
    }
    

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19. articles[0]["author"]["name"]
    

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20. "/articles"
    

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21. "name"
    

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22. "nme"
    

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23. - age
    + birthday
    

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26. MAPPING
    

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27. HTTP
    JSON
    MODEL MAPPING
    TESTS (STUBS & FIXTURES)
    DOMAIN LOGIC?
    

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28. $ cloc **Model**.{h,m} **API**.{h,m}
    95 text files.
    83 unique files.
    0 files ignored.
    -------------------------------------------------------------------------------
    Language files blank comment code
    -------------------------------------------------------------------------------
    Objective C 51 1420 499 5598
    C/C++ Header 32 258 480 479
    -------------------------------------------------------------------------------
    SUM: 83 1678 979 6077
    -------------------------------------------------------------------------------
    

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29. 6077 LINES OF CODE
    

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30. ANDROID
    

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31. 15,000
    LINES OF CODE
    

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32. WINDOWS
    PHONE
    

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33. 20,000
    LINES OF CODE
    

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34. ...
    

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35. 30,000
    LINES OF CODE
    

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36. BUILDING an
    API CLIENT
    

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37. DOMAIN-SPECIFIC
    

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38. INTEGRATED
    

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39. MIXING PROTOCOL
    SEMANTICS
    

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40. WHAT DOES THE API
    LOOK LIKE?
    

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44. GETTING
    STARTED
    

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45. TESTS
    

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46. MOCK
    

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47. [OHHTTPStubs stubRequestsPassingTest:^BOOL(NSURLRequest *request) {
    return ([request.URL.host isEqualToString:@"trunk.cocoapods.org"] &&
    [request.URL.path isEqualToString:@"/api/v1/sessions"]);
    } withStubResponse:^ OHHTTPStubsResponse *(NSURLRequest *request) {
    NSString *fixture = OHPathForFileInBundle(@"sessions.json", nil);
    NSDictionary *headers = @{
    @"Content-Type": @"application/json"
    };
    return [OHHTTPStubsResponse responseWithFileAtPath:fixture
    statusCode:200 headers:headers];
    }];
    

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48. {
    "created_at": "2014-04-21 23:08:00 +0200",
    "email": "kyle@cocoapods.org",
    "name": "Kyle Fuller",
    "sessions": [
    {
    "created_at": "2014-05-04 15:20:19 +0200",
    "valid_until": "2014-09-09 15:20:19 +0200",
    "verified": false
    },
    {
    "created_at": "2014-05-04 15:20:20 +0200",
    "valid_until": "2014-09-09 15:20:20 +0200",
    "verified": true
    }
    ]
    }
    

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49. AND REPEAT
    

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51. CAN’T WE USE THIS?
    

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52. UNDERSTANDABLE
    by machines
    

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53. POWERING YOUR TESTS
    with API BLUEPRINT
    

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54. pod `CCLRequestReplay`
    

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55. [OHHTTPStubs stubRequestsPassingTest:^BOOL(NSURLRequest *request) {
    return ([request.URL.host isEqualToString:@"trunk.cocoapods.org"] &&
    [request.URL.path isEqualToString:@"/api/v1/sessions"]);
    } withStubResponse:^ OHHTTPStubsResponse *(NSURLRequest *request) {
    NSString *fixture = OHPathForFileInBundle(@"sessions.json", nil);
    NSDictionary *headers = @{
    @"Content-Type": @"application/json"
    };
    return [OHHTTPStubsResponse responseWithFileAtPath:fixture
    statusCode:200 headers:headers];
    }];
    [OHHTTPStubs stubRequestsPassingTest:^BOOL(NSURLRequest *request) {
    return ([request.URL.host isEqualToString:@"trunk.cocoapods.org"] &&
    [request.URL.path isEqualToString:@"/api/v1/pods"]);
    } withStubResponse:^ OHHTTPStubsResponse *(NSURLRequest *request) {
    NSString *fixture = OHPathForFileInBundle(@"pods.json", nil);
    NSDictionary *headers = @{
    @"Content-Type": @"application/json"
    };
    return [OHHTTPStubsResponse responseWithFileAtPath:fixture
    statusCode:200 headers:headers];
    }];
    [OHHTTPStubs stubRequestsPassingTest:^BOOL(NSURLRequest *request) {
    return ([request.URL.host isEqualToString:@"trunk.cocoapods.org"] &&
    [request.URL.path isEqualToString:@"/api/v1/pod/../owners"]);
    } withStubResponse:^ OHHTTPStubsResponse *(NSURLRequest *request) {
    NSString *fixture = OHPathForFileInBundle(@"pod-querykit-owners.json", nil);
    NSDictionary *headers = @{
    @"Content-Type": @"application/json"
    };
    return [OHHTTPStubsResponse responseWithFileAtPath:fixture
    statusCode:200 headers:headers];
    }];
    ...
    

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56. {
    "created_at": "2014-04-21 23:08:00 +0200",
    "email": "kyle@cocoapods.org",
    "name": "Kyle Fuller",
    "sessions": [
    {
    "created_at": "2014-05-04 15:20:19 +0200",
    "valid_until": "2014-09-09 15:20:19 +0200",
    "verified": false
    },
    {
    "created_at": "2014-05-04 15:20:20 +0200",
    "valid_until": "2014-09-09 15:20:20 +0200",
    "verified": true
    }
    ]
    }
    {
    "name": "QueryKit",
    "version": "0.8.3",
    "authors": {
    "Kyle Fuller": "inbox@kylefuller.co.uk"
    },
    "social_media_url": "http://twitter.com/kylefuller",
    "source": {
    "git": "https://github.com/QueryKit/QueryKit.git",
    "tag": "0.8.3"
    },
    "source_files": [
    "QueryKit/*.{h}",
    "QueryKit/ObjectiveC/*.{h,m}"
    ],
    "requires_arc": true
    }
    ...
    

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57. let URL = NSBundle.mainBundle().URIForResource("palaver", withExtension:"apib.json")
    requestReplayManager.addRecordings(fromBlueprintURL:URL, error:nil)
    

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58. GET /sessions
    

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60. EMBRACE
    CHANGE
    

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62. WE MADE A
    MISTAKE.
    

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63. WE WANT TO CHANGE...
    ENDPOINT URI.
    

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64. NEGOTIATE AT
    RUN-TIME
    

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65. WE WANT TO CHANGE...
    PAGINATION LOGIC.
    

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66. FOLLOWING
    LINKS
    

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67. TRANSITION
    BETWEEN STATES
    

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68. "Paging is achieved with the
    published_before
    parameter."
    

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69. published_before
    

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70. [
    {
    "published_date": "2013-04-30T16:05:45+00:00",
    ...
    }
    ]
    

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71. GET /articles?published_before=2013-04-30T16:05:45+00:00
    

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72. SERVER LOGIC
    

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73. Next Page =
    

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74. Prevent
    BREAKING
    CHANGES
    

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75. BUILDING BETTER CLIENTS
    from THE API
    

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76. FLEXIBILITY
    

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77. CASCADED
    REQUESTS
    

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78. GET /categories
    GET /authors
    GET /articles
    

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79. BANDWIDTH
    

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80. LARGE DATA
    

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81. $ curl -I http://api.something.com/articles
    HTTP/1.1 200 OK
    Content-Type: application/json
    Content-Length: 12524998
    

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82. BREAK IT UP
    

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83. PAGINATION
    

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84. /list
    VS
    /list/detail
    

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85. USE Last-Modified
    

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86. USE Cache-Control
    

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87. USE STANDARDS
    

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88. LET’S BUILD BETTER APIS
    TOGETHER
    

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89. KYLE FULLER
    

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