OHHTTPStubs

OHHTTPStubs is a library designed to stub your network requests very easily. It can help you:

test your apps with fake network data (stubbed from file) and simulate slow networks, to check your application behavior in bad network conditions
write Unit Tests that use fake network data from your fixtures.

It works with NSURLConnection, new iOS7/OSX.9's NSURLSession, AFNetworking (both 1.x and 2.x), or any networking framework that use Cocoa's URL Loading System.

Documentation & Usage Examples

OHHTTPStubs headers are fully documented using Appledoc-like / Headerdoc-like comments in the header files. You can also read the online documentation here

Swift support

OHHTTPStubs is compatible with Swift out of the box: you can use it with the same API as you would use in Objective-C. But you might also want to include the OHHTTPStubs/Swift subspec in your Podfile, which adds some global function helpers (see OHHTTPStubsSwift.swift) to make the use of OHHTTPStubs more compact and Swift-like.

Basic example

In Objective-C

[OHHTTPStubs stubRequestsPassingTest:^BOOL(NSURLRequest *request) {
  return [request.URL.host isEqualToString:@"mywebservice.com"];
} withStubResponse:^OHHTTPStubsResponse*(NSURLRequest *request) {
  // Stub it with our "wsresponse.json" stub file (which is in same bundle as self)
  NSString* fixture = OHPathForFile(@"wsresponse.json", self.class);
  return [OHHTTPStubsResponse responseWithFileAtPath:fixture
            statusCode:200 headers:@{@"Content-Type":@"application/json"}];
}];

In Swift

This example is using the Swift helpers found in OHHTTPStubsSwift.swift provided by the OHHTTPStubs/Swift subspec

stub(isHost("mywebservice.com")) { _ in
  // Stub it with our "wsresponse.json" stub file (which is in same bundle as self)
  let stubPath = OHPathForFile("wsresponse.json", self.dynamicType)
  return fixture(stubPath!, headers: ["Content-Type":"application/json"])
}

Notes

Using OHHTTPStubsSwift.swift you could also compose the matcher functions like this: stub(isScheme("http") && isHost("myhost")) { … }
The response files used above can be recorded with tools like SWHttpTrafficRecorder. It can record all three formats that are supported by OHHTTPStubs, that is, HTTPMessage, response boby/content file, and Mocktail.

More examples & Help Topics

For a lot more examples, see the dedicated "Usage Examples" wiki page.
The wiki also contain some articles that can help you get started with (and troubleshoot if needed) OHHTTPStubs.

Compatibility

OHHTTPStubs is compatible with iOS 5.0+ and OSX 10.7+.

OHHTTPStubs also works with iOS7's and OSX 10.9's NSURLSession mechanism.

OHHTTPStubs is fully Swift-compatible. Nullability annotations have been added to allow a cleaner API when used from Swift.

Installing in your projects

Using CocoaPods is the recommended way. Simply add pod 'OHHTTPStubs' to your Podfile.

OHHTTPStubs should also be compatible with Carthage — but I won't guarantee help/support for it as I don't use it personally.

Special Considerations

Using OHHTTPStubs in your Unit Tests

OHHTTPStubs is ideal to write Unit Tests that normally would perform network requests. But if you use it in your Unit Tests, don't forget to:

remove any stubs you installed after each test — to avoid those stubs to still be installed when executing the next Test Case — by calling [OHHTTPStubs removeAllStubs] in your tearDown method. see this wiki page for more info
be sure to wait until the request has received its response before doing your assertions and letting the test case finish (like for any asynchronous test). see this wiki page for more info

Automatic loading

Thanks to method swizzling, OHHTTPStubs is automatically loaded and installed both for:

requests made using NSURLConnection or [NSURLSession sharedSession];
requests made using a NSURLSession created using a [NSURLSessionConfiguration defaultSessionConfiguration] or [NSURLSessionConfiguration ephemeralSessionConfiguration] configuration (using [NSURLSession sessionWithConfiguration:…]-like methods).

If you need to disable (and re-enable) OHHTTPStubs — globally or per NSURLSession — you can use [OHHTTPStubs setEnabled:] / [OHHTTPStubs setEnabled:forSessionConfiguration:].

Known limitations

OHHTTPStubs can't work on background sessions (sessions created using [NSURLSessionConfiguration backgroundSessionConfiguration]) because background sessions don't allow the use of custom NSURLProtocols and are handled by the iOS Operating System itself.
OHHTTPStubs don't simulate data upload. The NSURLProtocolClient @protocol does not provide a way to signal the delegate that data has been sent (only that some has been loaded), so any data in the HTTPBody or HTTPBodyStream of an NSURLRequest, or data provided to -[NSURLSession uploadTaskWithRequest:fromData:]; will be ignored, and more importantly, the -URLSession:task:didSendBodyData:totalBytesSent:totalBytesExpectedToSend: delegate method will never be called when you stub the request using OHHTTPStubs.

As far as I know, there's nothing we can do about those two limitations. Please let me know if you know a solution that would make that possible anyway.

Submitting to the AppStore

OHHTTPStubs can be used on apps submitted on the AppStore. It does not use any private API and nothing prevents you from shipping it.

But you generally only use stubs during the development phase and want to remove your stubs when submitting to the AppStore. So be careful to only include OHHTTPStubs when needed (only in your test targets, or only inside #if DEBUG portions, or by using per-Build-Configuration pods) to avoid forgetting to remove it when the time comes that you release for the AppStore and you want your requests to hit the net!

License and Credits

This project and library has been created by Olivier Halligon (@aligatr on Twitter) and is under the MIT License.

It has been inspired by this article from InfiniteLoop.dk.

I would also like to thank Kevin Harwood (@kcharwood) for migrating the code to NSInputStream, Jinlian Wang (@JinlianWang) for adding Mocktail support, and everyone else who contributed to this project on GitHub somehow.

If you want to support the development of this library, feel free to . Thanks to all contributors so far!

Ashton-W/OHHTTPStubs