How to handle large file uploads via WCF?

Question

I am looking into using WCF for a project which would require the ability for people to upload large files (64MB-1GB) to my server. How would I handle this with WCF, possibl

Answer 1

If you want to upload large files, you'll definitely need to look into WCF Streaming Mode.

Basically, you can change the transfer mode on your binding; by default, it's buffered, i.e. the whole message needs to be buffered on the sender, serialized, and then transmitted as a whole.

With Streaming, you can define either one-way streaming (for uploads only, for downloads only) or bidirectional streaming. This is done by setting the transferMode of your binding to StreamedRequest, StreamedResponse, or just plain Streamed.

<bindings>
   <basicHttpBinding>
      <binding name="HttpStreaming" 
               maxReceivedMessageSize="2000000"
               transferMode="StreamedRequest"/>
   </basicHttpBinding>
</bindings>

Then you need to have a service contract which either receives a parameter of type Stream (for uploads), or returns a value of type Stream (for downloads).

[ServiceContract]
public interface IFileUpload
{
    [OperationContract]
    bool UploadFile(Stream stream);
}

That should do it!

Answer 2

You can use webHttpBinding with TransferMode streamed and a single Stream parameter or Stream response (as appropriate) for large file up/downloads, but you'd have to send any request metadata via URLs and/or headers, unless you're going to devise your own framing on the Stream. You'll have to build a custom non-HTML client (like Silverlight, Flash, etc) though, since browsers don't support random access to local files, and the normal file upload will be a form post, not JSON.

Answer 3

MTOM is optimized to handle large binary data.