title: AFNetworking with AFJSONRequestOperation and filedata never completes
body: <p>I'm using AFNetworking to post json data to my webservice and get a json response back. However now I also want to add multipart formdata to these POST's. If I do this (even without the parameters I added first) the completion block never fires. The progress block DOES fire and I can see that the file uploads correctly.</p>
  
  <p>Does anybody have any experience posting images like this with AFNetworking? I am using the latest AFNetworking source / version.</p>
  
  <p>This is my initial code for posting a dictionary with json in it. This works fine.</p>
  
  <pre><code>NSMutableDictionary *postdata = [[NSMutableDictionary alloc] init];
  [postdata setObject:[postdictionary JSONString] forKey:@"request"];
  
  NSMutableURLRequest *jsonRequest = [httpClient requestWithMethod:@"POST"
                                             path:path
                                       parameters:postdata];
  
  AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:jsonRequest success:^(NSURLRequest *request,     NSHTTPURLResponse *response, id JSON) {// Success} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {// Failure }];
  
  [operation start];
  </code></pre>
  
  <p>This is the version of the code for submitting an image (doesn't work)</p>
  
  <pre><code>NSMutableURLRequest *jsonRequest jsonRequest = [httpClient   multipartFormRequestWithMethod:@"POST" path:path parameters:postdata constructingBodyWithBlock: ^(id &lt;AFMultipartFormData&gt; formData) {
      [formData appendPartWithFileData:imageData name:@"photo" fileName:@"photo.jpg" mimeType:@"image/jpeg"];
      [formData throttleBandwidthWithPacketSize:5000 delay:0.1];
  }];
  
  AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:jsonRequest];
  [operation setUploadProgressBlock:^(NSUInteger bytesWritten, long long  totalBytesWritten, long long totalBytesExpectedToWrite) {
      NSLog(@"Sent %lld of %lld bytes", totalBytesWritten, totalBytesExpectedToWrite);
  }];
  
  [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
      NSLog(@"Upload succes");
  } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
      NSLog(@"Upload failed");
  }];
  
  [operation start];
  </code></pre>