Bind RAC to AFNetworking

gistfile1.m

- (RACSignal *)enqueueRequestWithMethod:(NSString *)method path:(NSString *)path parameters:(NSDictionary *)parameters cacheTime:(NSTimeInterval)expirationTime {
	NSAssert(self.cluster, @"cluster should be set before request.");
	NSAssert(self.applicationID.length != 0, @"applicationID should be set before request.");
	
	NSMutableURLRequest *request = [self requestWithMethod:method path:path parameters:parameters];
	
	RACSignal *signal = [RACSignal createSignal:^(id<RACSubscriber> subscriber) {
		AFHTTPRequestOperation *operation;
		operation = [self HTTPRequestOperationWithRequest:request success:^(AFHTTPRequestOperation *op, id JSON) {
			NSDictionary *errorDictionary = JSON[@"error"];
			if (errorDictionary){
				NSError *error = [NSError errorWithDomain:WGNClientErrorDomain
													 code:[errorDictionary[@"code"] integerValue]
												 userInfo:@{NSLocalizedDescriptionKey:errorDictionary[@"message"]}];
				[subscriber sendError:error];
			}else{
				[subscriber sendNext:JSON];
				[subscriber sendCompleted];
			}
		} failure:^(AFHTTPRequestOperation *op, NSError *error) {
			if (![op isCancelled]) {
				[subscriber sendError:error];
			}
		}];
		[self enqueueHTTPRequestOperation:operation];
		
		return [RACDisposable disposableWithBlock:^{
			[operation cancel];
		}];
	}];
	
	return [[signal replayLazily] setNameWithFormat:@"-enqueueRequest:%@", request];
}