Question

I am creating an application in .NET that will serve as a second UI for my already-deployed Django app. For some operations users need to authenticate themselves (as Django users). I used a super-simple way to do this (without encrypting credentials for simplicity):-

Step 1. I created a django view that accepted the username and password through two HTTP GET parameters and passed them on to django.contrib.auth.authenticate() as keyword arguments. See the code below:

     def authentication_api(request, raw_1, raw_2):         user = authenticate(username=raw_1, password=raw_2)         if user is not None:             if user.is_active:                 return HttpResponse('correct', mimetype='text/plain')             else:                 return HttpResponse('disabled', mimetype='text/plain')         else:             return HttpResponse('incorrect', mimetype='text/plain')

Step 2. I called this using the following code in .NET. The ‘strAuthURL’ in the following representes a simple django URL mapped to the django view above:

     Dim request As HttpWebRequest = CType(WebRequest.Create(strAuthURL), HttpWebRequest)     Dim response As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)     Dim reader As StreamReader = New StreamReader(response.GetResponseStream())     Dim result As String = reader.ReadToEnd()     HttpWResp.Close()

This works flawlessly, although it is nothing more than a proof-of-concept.

Now I want to do this via HTTP POST so I have done the following: –

I created a django view for the doing authentication using POST data

     def post_authentication_api(request):         if request.method == 'POST':             user = authenticate(username=request.POST['username'], password=request.POST['password'])             if user is not None:                 if user.is_active:                     return HttpResponse('correct', mimetype='text/plain')                 else:                     return HttpResponse('disabled', mimetype='text/plain')             else:                 return HttpResponse('incorrect', mimetype='text/plain')

I have tested this using restclient and this view works as expected. However I can't get it to work from the .NET code below:

     Dim request As HttpWebRequest = CType(WebRequest.Create(strAuthURL), HttpWebRequest)     request.ContentType = 'application/x-www-form-urlencoded'     request.Method = 'POST'     Dim encoding As New UnicodeEncoding     Dim postData As String = 'username=' & m_username & '&password=' & m_password     Dim postBytes As Byte() = encoding.GetBytes(postData)     request.ContentLength = postBytes.Length     Try         Dim postStream As Stream = request.GetRequestStream()         postStream.Write(postBytes, 0, postBytes.Length)         postStream.Close()         Dim response As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)         Dim responseStream As New StreamReader(response.GetResponseStream(), UnicodeEncoding.Unicode)         result = responseStream.ReadToEnd()         response.Close()     Catch ex As Exception         MessageBox.Show(ex.ToString)     End Try

The server is giving me a 500 internal server error. My guess is that the POST request is not properly set up in .NET. So I basically need some guidance on how to call the django view from .NET sending POST data.

Thanks, CM

Answer 1

Looks ok to me. I recommend using Wireshark to see what your restclient is sending in the headers and and see what your app sending in the headers.