Question

I have an Android application with an ASP.NET backend. I have the registration_id for the phone as well as an auth token from google for the application server that is performing a push.

When I make the http post request to C2DM so that the phone gets a message I keep getting the 401 Unauthorized. Here is how I’m making the request in .NET:

    WebRequest myRequest = WebRequest.Create("https://android.apis.google.com/c2dm/send");
    myRequest.ContentType = "application/x-www-form-urlencoded";
    myRequest.Method = "POST";
    myRequest.Headers.Add("Authorization", "GoogleLogin auth=" + authId);
    // buiold the post string
    StringBuilder myPost = new StringBuilder();
    myPost.AppendFormat("registration_id={0}", regId);
    myPost.AppendFormat("&data.payload={0}", msg);
    myPost.AppendFormat("&collapse_key={0}", colKey);

    // write the post-string as a byte array
    byte[] myData = ASCIIEncoding.ASCII.GetBytes(myPost.ToString());
    myRequest.ContentLength = myData.Length;
    Stream myStream = myRequest.GetRequestStream();
    myStream.Write(myData, 0, myData.Length);
    myStream.Close();
    // Do the actual request and read the response stream
    WebResponse myResponse = myRequest.GetResponse();
    Stream myResponseStream = myResponse.GetResponseStream();
    StreamReader myResponseReader = new StreamReader(myResponseStream);
    string strResponse = myResponseReader.ReadToEnd();
    myResponseReader.Close();
    myResponseStream.Close();

Any help would be much appreciated.

Answer 1

Advice corner: Have some confidence in your code every once and a while! And, even Google messes up sometimes.

After spending about nine hours reading every blog post and article about Google OAuth and C2DM and trying different things in my code, I emailed Google. I’m excited to say that not only did I receive a response very quickly, but also that my account was messed up. Something went wrong while I was registering on their site and although it appeared that everything was working from the registration success email I received, it wasn’t. I re-registered and everything works!