RxSwift.md

RxSwift

Moya provides an optional RxMoyaProvider subclass of MoyaProvider that does a few interesting things. Instead of calling the request() method and providing a callback closure to be executed when the request completes, we use Observables.

A RxMoyaProvider can be created much like a MoyaProvider and can be used as follows:

let provider = RxMoyaProvider<GitHub>()

After that simple setup, you're off to the races:

provider.request(.Zen).subscribe { (event) -> Void in
    switch event {
    case .Next(let response):
        // do something with the data
    case .Error(let error):
        // handle the error
    default:
        break
    }
}

For RxMoyaProvider, the network request is not started until the signal is subscribed to. If the subscription to the signal is disposed of before the request completes, the request is cancelled.

If the request completes normally, two things happen:

1. The observable sends a value, a Moya.Response instance.
2. The observable completes.

If the request produces an error (typically a NSURLSession error), then it sends an error, instead. The error's code is the failing request's status code, if any, and the response data, if any.

The Moya.Response class contains a statusCode, some data, and a(n optional) NSURLResponse. You can use these values however you like in subscribeNext or map calls.

To make things even awesomer, Moya provides some extensions to Observable that make dealing with MoyaResponsesreally easy.

• filterStatusCodes() takes a range of status codes. If the response's status code is not within that range, an error is produced.
• filterStatusCode() looks for a specific status code, and errors if it finds anything else.
• filterSuccessfulStatusCodes() filters status codes that are in the 200-range.
• filterSuccessfulStatusAndRedirectCodes() filters status codes that are in the 200-300 range.
• mapImage() tries to map the response data to a UIImage instance and errors if unsuccessful.
• mapJSON() tries to map the response data to a JSON object and errors if unsuccessful.
• mapString() tries to map the response data to a string and errors if unsuccessful.

In the error cases, the error's domain is MoyaErrorDomain. The code is one of MoyaErrorCode's rawValues, where appropriate. Wherever possible, underlying errors are provided and the original response data is included in the NSError's userInfo dictionary using the "data" key.