OHHttpStubs

OHHttpStubs

• 1.
  Sébastien Duperron @liquidseb Refactoring andimplementing the (near) future OHHTTPStubs CocoaHeads Paris 11 février 2016
• 2.
  Your App Stubs 🚫 How it works Network
• 3.
  What it does Interceptnetwork requests: • Fake network data using files or code • Simulate slow network conditions
• 4.
  Where you canuse it • Unit tests / UI tests • Slow network integration tests • Features with yet to implement web services
• 5.
  Limitations • Do notsupport Background sessions • Cannot stub data upload
• 6.
  How to implementit Content Request Objective-C
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  How to implementit Content Request Swift
• 8.
  How to implementit - (void)testFoo { NSURLRequest* request = ... XCTestExpectation* responseArrived = [self expectationWithDescription:@"response of async request has arrived"]; __block NSData* receivedData = nil; [NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse* response, NSData* data, NSError* error) { receivedData = data; [responseArrived fulfill]; } ]; [self waitForExpectationsWithTimeout:timeout handler:^{ XCTAssertNotNil(receivedData, @"Received data should not be nil"); }]; } UnitTest asynchronous example
• 9.
  How to implementit Remove stubs in UnitTest tearDown - (void)tearDown { [OHHTTPStubs removeAllStubs]; [super tearDown]; } ⚠ ⚠
• 10.
  Response API • NSData •Path • JSON object Successful request response return [OHHTTPStubsResponse responseWithFileAtPath:OHPathForFile(@"wsresponse.json",self.class) statusCode:200 headers:@{@"Content-Type":@"application/json"}]; NSDictionary* obj = @{ @"key1": @"value1", @"key2": @[@"value2A", @"value2B"] }; return [OHHTTPStubsResponse responseWithJSONObject:obj statusCode:200 headers:nil]; NSData* stubData = [@"Hello World!" dataUsingEncoding:NSUTF8StringEncoding]; return [OHHTTPStubsResponse responseWithData:stubData statusCode:200 headers:nil];
• 11.
  Response API Failed request NSError*notConnectedError = [NSError errorWithDomain:NSURLErrorDomain code:kCFURLErrorNotConnectedToInternet userInfo:nil]; return [OHHTTPStubsResponse responseWithError:notConnectedError]; NSError
• 12.
  Response API • requestTime •responseTime Request / Response delay OHHTTPStubsDownloadSpeed1KBPS OHHTTPStubsDownloadSpeedSLOW OHHTTPStubsDownloadSpeedGPRS OHHTTPStubsDownloadSpeedEDGE OHHTTPStubsDownloadSpeed3G OHHTTPStubsDownloadSpeed3GPlus OHHTTPStubsDownloadSpeedWifi Special values
• 13.
  Response API You canchain responseTime: method call Request / Response delay return [[OHHTTPStubsResponse responseWithData:[NSData data] statusCode:400 headers:nil] responseTime:OHHTTPStubsDownloadSpeed3G]
• 14.
  First example Refactoring ournetwork code
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  Our context • Twonetwork modules: 1 legacy with NSURLConnection 1 new with AFNetworking • Server and App code with little or no documentation • No tests
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  Can’t we justrewrite the old code and be done with it ? Of course. But what about regressions?
• 17.
  But we cannotwrite tests on the old network code?! • new API is different (block callbacks vs delegation to objects) • network logic is mostly inside controllers
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  What we have Controller Request ManualObject Mapping Legacy Network Module NSURLConnection How do we test this ?
• 19.
  What do wedo in a test? • Given a set of inputs • When operating on this set • Then check the outputs
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  How do wetest this? Controller Request Manual Object Mapping Legacy Network Module NSURLConnection OHHTTPStubs • check network call • return expected JSON data Check mappingTest call
• 21.
  How do wedo this? 1.Gather existing requests with corresponding responses 2.Use OHHTTPStubs to stub the requests 3.Implement tests on existing code 4.Refactor!
• 22.
  Controller Before/After refactoring Controller Request Manual Object Mapping LegacyNetwork Module NSURLConnection New Network Module AFNetworking Automatic Object Mapping Previous implementation New implementation Requests Factory
• 23.
  Second example Stubbing yet-to-implementweb services
• 24.
  Context • All teamshave different roadmaps (mostly) • This means milestones (which are sometimes deadlines)
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  Roadmap iOS team Server team THEfeature Other important stuff Webservice for THE feature Release deadline T Apple Review
• 26.
  How can weachieve this? • Specify the web service entry point precisely (parameters and output data) • Stub the request using this specification • Develop the feature (with its tests!)
• 27.
  How can weachieve this? OHHTTPStubs JSON Files NSURLConnection NSURLSession
• 28.
  What we haveused JSON configuration files }Stubbed request }JSON stub
• 29.
  https://github.com/AliSoftware/OHHTTPStubs Sébastien Duperron -@liquidseb Viadeo Maintainer: Olivier Halligon (@aligatr) Questions ? OHHTTPStubs