PUT with WWWform

From what I can tell, WWW creates GET requets and WWWform will create POST requests. While these are great. I was hoping to follow more REST standards and also use PUT and DELETE.

Are these functions built into WWW or WWWform? If not, Sign me up to the developers and I’ll get it in there. Modifying WWWform to allow for ‘PUT’ instead of ‘POST’ should be as simple as adding an optional parameter for ‘HTTP_METHOD’ Its quite literally the same thing only changing the first letters of the request from POST to PUT.

Anyone know a way? …so that I don’t need to badger Unity to let me develop it for them?

Love,
Hepallucion

P.S. Yes, I could re-write my server to only use POST and GET, but I’d rather not, REST makes sense.

Hey guys,

Here’s a simple solution if you’re working with MVC, but it can surely be be adapted to other platforms also. I initially wrote my client messaging layer around WebRequest, which has full support for CRUD but found that eventually with bigger data it caused unity to stutter, even when threaded.

When moving back to Unity’s WWW I came across the lack of PUT and DELETE which my client was now coupled with. To avoid spending the time required to re-write all the PUT and DELETE MVC server functions, I came up with the following solution:

First, add the following header to your WWW request:

 var headers = new Dictionary<string, string>();
 headers.Add("X-HTTP-Method-Override", "PUT");

Then perform the WWW POST request as normal:

 var request = new UnityEngine.WWW(_uri, _putBytes, headers);
 yield return request;
 Debug.Log(request.text);

The server receives the sent POST request, but we area able to intercept the message by adding a new method handler which is run over the message before it is passed to the server’s functions, and we change the request’s method to PUT instead of POST:

public class MethodOverrideHandler : DelegatingHandler
{
    readonly string[] _methods = { "DELETE", "HEAD", "PUT" };
    const string _header = "X-HTTP-Method-Override";
 
    protected override Task<HttpResponseMessage> SendAsync(
        HttpRequestMessage request, CancellationToken cancellationToken)
    {
        // Check for HTTP POST with the X-HTTP-Method-Override header.
        if (request.Method == HttpMethod.Post && request.Headers.Contains(_header))
        {
            // Check if the header value is in our methods list.
            var method = request.Headers.GetValues(_header).FirstOrDefault();
            if (_methods.Contains(method, StringComparer.InvariantCultureIgnoreCase))
            {
                // Change the request method.
                request.Method = new HttpMethod(method);
            }
        }
        return base.SendAsync(request, cancellationToken);
    }
}

Add the following line to the server solution’s WebApiConfig.cs:

 public static void Register(HttpConfiguration config)
 {
      config.MessageHandlers.Add(new MethodOverrideHandler());
 ...

This way, without re-factoring any of the business layer for either the client or server we can overcome the lack of PUT and DELETE in Unity’s WWW class. If anyone wants any more info on the process, there’s a great article by Scott Hanselman that provided me with the solution.

This is now completed in UnityEngine.Experimental.Networking as of Unity 5.2 and 5.3, with more platforms supported in further releases. Here is the official documentation:

Unfortunately, Unity’s built-in WWW class only supports GET and POST.

Fortunately, Unity supports just about any Mono-compatible .NET library you’re able to import. You should be able to find plenty of suitable HTTP libraries online, and some of them are even built specifically to support Unity.

The best way is:

var wr = new UnityWebRequest("http://example.com", "PUT");
SetupPut(wr, postFormData);

.
.

void SetupPut(UnityWebRequest request, WWWForm formData)
  {
    byte[] data = null;
    if (formData != null)
    {
      data = formData.data;
      if (data.Length == 0)
        data = null;
    }
    request.uploadHandler = new UploadHandlerRaw(data);
    request.downloadHandler = new DownloadHandlerBuffer();
    if (formData == null)
      return;
    foreach (KeyValuePair<string, string> header in formData.headers)
      request.SetRequestHeader(header.Key, header.Value);
  }