Reacting to Change - API Days 2014

Transcript

1. REACTING TO CHANGE ! KYLE FULLER
2. BUILDING better API CLIENTS
5. DOZENS of APPS
6. HTTP / APIS
7. THERE’S AN API
8. COMPONENTS OF AN API CLIENT
9. perform(.RetrieveArticles) { result in switch result { case .Success(let representor): /* We've got some articles */ case .Error(let error): /* We hit an error */ } }
10. FOUNDATION
11. NSURLSession OR NSURLConnection
12. NSURLRequest
13. NSURLHTTPResponse
14. SIMPLE...
15. HTTP SEMANTICS
16. SERIALISATION (JSON)
17. CONVERT to VALUE-MODELS
18. struct Article { let title:String let body:String let author:Author let image:[NSURL] } struct Author { let name:String let twitter:String }
19. articles[0]["author"]["name"]
20. "/articles"
21. "name"
22. "nme"
23. - age + birthday
26. MAPPING
27. HTTP JSON MODEL MAPPING TESTS (STUBS & FIXTURES) DOMAIN LOGIC?
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 -------------------------------------------------------------------------------
29. 6077 LINES OF CODE
30. ANDROID
31. 15,000 LINES OF CODE
32. WINDOWS PHONE
33. 20,000 LINES OF CODE
34. ...
35. 30,000 LINES OF CODE
36. BUILDING an API CLIENT
37. DOMAIN-SPECIFIC
38. INTEGRATED
39. MIXING PROTOCOL SEMANTICS
40. WHAT DOES THE API LOOK LIKE?
44. GETTING STARTED
45. TESTS
46. MOCK
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]; }];
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 } ] }
49. AND REPEAT
51. CAN’T WE USE THIS?
52. UNDERSTANDABLE by machines
53. POWERING YOUR TESTS with API BLUEPRINT
54. pod `CCLRequestReplay`
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]; }]; ...
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 } ...
57. let URL = NSBundle.mainBundle().URIForResource("palaver", withExtension:"apib.json") requestReplayManager.addRecordings(fromBlueprintURL:URL, error:nil)
58. GET /sessions
60. EMBRACE CHANGE
62. WE MADE A MISTAKE.
63. WE WANT TO CHANGE... ENDPOINT URI.
64. NEGOTIATE AT RUN-TIME
65. WE WANT TO CHANGE... PAGINATION LOGIC.
66. FOLLOWING LINKS
67. TRANSITION BETWEEN STATES
68. "Paging is achieved with the published_before parameter."
69. published_before
70. [ { "published_date": "2013-04-30T16:05:45+00:00", ... } ]
71. GET /articles?published_before=2013-04-30T16:05:45+00:00
72. SERVER LOGIC
73. Next Page = <some URI>
74. Prevent BREAKING CHANGES
75. BUILDING BETTER CLIENTS from THE API
76. FLEXIBILITY
77. CASCADED REQUESTS
78. GET /categories GET /authors GET /articles
79. BANDWIDTH
80. LARGE DATA
81. $ curl -I http://api.something.com/articles HTTP/1.1 200 OK Content-Type: application/json Content-Length: 12524998
82. BREAK IT UP
83. PAGINATION
84. /list VS /list/detail
85. USE Last-Modified
86. USE Cache-Control
87. USE STANDARDS
88. LET’S BUILD BETTER APIS TOGETHER
89. KYLE FULLER