FutureKit+AlamoFire.swift

FutureKit+AlamoFire.swift

//
//  FutureKit+AlamoFire.swift
//
//  Created by Michael Gray on 9/21/15.
//

import Foundation
import Alamofire
import FutureKit

extension Request {
    
    // so AlamoFire uses V as the Value Type and T as the serializer type.  Letters gotta match here or swift 2.0 gets superconfused.
    
    func future<T: ResponseSerializerType>(responseSerializer s: T) -> Future<T.SerializedObject> {
        let p = Promise<T.SerializedObject>()
        p.onRequestCancel { _  in
            self.cancel()       // AlamoFire will send NSURLErrorDomain,.NSURLErrorCancelled error if cancel is successful
            return .Continue    // wait for NSError to arrive before canceling future.
        }
        
        self.response(queue: nil, responseSerializer: s) { response -> Void in
            switch response.result {
            case let .Success(t):
                p.completeWithSuccess(t)
            case let .Failure(error):
                let e = error as NSError
                if (e.domain == NSURLErrorDomain) && (e.code == NSURLErrorCancelled) {
                    p.completeWithCancel()
                }
                else {
                    p.completeWithFail(error)
                }
            }
        }

        
        return p.future
        
    }

    func futureNSData() -> Future<NSData> {
        return future(responseSerializer:Request.dataResponseSerializer())
    }

    // uses NSJSONSerialization
    func futureJSONObject(options: NSJSONReadingOptions = .AllowFragments) -> Future<AnyObject> {
        return future(responseSerializer:Request.JSONResponseSerializer(options: options))
    }
    
    func futureString(encoding: NSStringEncoding? = nil) -> Future<String> {
        return future(responseSerializer:Request.stringResponseSerializer(encoding: encoding))
    }
    func futurePropertyList(options: NSPropertyListReadOptions = []) -> Future<AnyObject> {
        return future(responseSerializer:Request.propertyListResponseSerializer(options: options))
    }
    
    
}