Question

I have been searching for 2 days for an answer, but nothing came up.

I am trying to make integrate Oauth2 for login with Google on Django. The code I have throws an exception – “The token is invalid”.

This happens:

resp, content = client.request(access_token_url, "POST")
    if resp['status'] != '200':
        print content
        raise Exception("Invalid response from Google."+content)

in google_authenticate()

Please, help me.

My code:

    def google_login(request):
    scope = "https://www.googleapis.com/auth/userinfo.profile"

    request_token_url = "https://www.google.com/accounts/OAuthGetRequestToken?scope=%s" % scope
    authorize_url = 'https://www.google.com/accounts/OAuthAuthorizeToken'
    authenticate_url = "https://accounts.google.com/o/oauth2/auth"

    response_type = "code"
    redirect_uri = "http://127.0.0.1:8000/login/google/auth"
    scope = "https://www.googleapis.com/auth/userinfo.profile"

    oauth_key = settings.GOOGLE_KEY
    oauth_secret = settings.GOOGLE_SECRET

    consumer = oauth.Consumer(oauth_key, oauth_secret)
    client = oauth.Client(consumer)

    # Step 1: Get a request token. This is a temporary token that is used for 
    # having the user authorize an access token and to sign the request to obtain 
    # said access token.

    resp, content = client.request(request_token_url, "POST")
    request_token = dict(urlparse.parse_qsl(content))

    if resp['status'] != '200':
        raise Exception("Invalid response from Google.")

    # Step 2. Store the request token in a session for later use.
    request.session['request_token'] = dict(cgi.parse_qsl(content))

    # Step 3. Redirect the user to the authentication URL.
    url = "%s?oauth_token=%s&client_id=%s&response_type=%s&redirect_uri=%s&scope=%s" % (authenticate_url,
        request.session['request_token']['oauth_token'],
        oauth_key,response_type,redirect_uri,scope)

    return HttpResponseRedirect(url)

def google_authenticate(request):
    access_token_url = 'https://www.google.com/accounts/OAuthGetAccessToken'

    oauth_key = settings.GOOGLE_KEY
    oauth_secret = settings.GOOGLE_SECRET

    consumer = oauth.Consumer(oauth_key, oauth_secret)

    # Step 1. Use the request token in the session to build a new client.
    token = oauth.Token(request.session['request_token']['oauth_token'],
        request.session['request_token']['oauth_token_secret'])
    if 'oauth_verifier' in request.GET:
        token.set_verifier(request.GET['oauth_verifier'])
    client = oauth.Client(consumer, token)

    # Step 2. Request the authorized access token from Google.
    resp, content = client.request(access_token_url, "POST")
    if resp['status'] != '200':
        print content
        raise Exception("Invalid response from Google."+content)

    access_token = dict(cgi.parse_qsl(content))

    # Step 3. Lookup the user or create them if they don't exist.
    try:
        user = User.objects.get(username=access_token['screen_name'])
    except User.DoesNotExist:
        # When creating the user I just use their [e-mail]
        # for their email and the oauth_token_secret for their password.
        # These two things will likely never be used. Alternatively, you 
        # can prompt them for their email here. Either way, the password 
        # should never be used.
        user = User.objects.create_user(access_token['screen_name'],
            '[e-mail]' % access_token['screen_name'],
            access_token['oauth_token_secret'])

        # Save our permanent token and secret for later.
        profile = Profile()
        profile.user = user
        profile.oauth_token = access_token['oauth_token']
        profile.oauth_secret = access_token['oauth_token_secret']
        profile.save()

    # Authenticate the user and log them in using Django's pre-built 
    # functions for these things.
    user = authenticate(username=access_token['screen_name'],
        password=access_token['oauth_token_secret'])
    login(request, user)

    return HttpResponseRedirect('/')

Answer 1

After a long time, and many hours spent gone to waste, I gave up with OAuth2 since it is difficult to configure, and all I need is to log a user in. The following code should help someone who needs to do something similar, and can be customized. All I did was follow the instructions on forming the urls and such here -> https://developers.google.com/accounts/docs/OAuth2Login

I made two views (for anyone not using Django – pages) and made a link to the first one:
This page I called login/google and made a link to it from the login page.

def google_login(request):
    token_request_uri = "https://accounts.google.com/o/oauth2/auth"
    response_type = "code"
    client_id = XXXXXX-your_client_id
    redirect_uri = "http://mysite/login/google/auth"
    scope = "https://www.googleapis.com/auth/userinfo.profile https://www.googleapis.com/auth/userinfo.email"
    url = "{token_request_uri}?response_type={response_type}&client_id={client_id}&redirect_uri={redirect_uri}&scope={scope}".format(
        token_request_uri = token_request_uri,
        response_type = response_type,
        client_id = client_id,
        redirect_uri = redirect_uri,
        scope = scope)
    return HttpResponseRedirect(url)

The above code redirected to the second page (this page must be defined as a redirect uri in the google app definitions).
I called this page login/google/auth:

def google_authenticate(request):
    parser = Http()
    login_failed_url = '/'
    if 'error' in request.GET or 'code' not in request.GET:
        return HttpResponseRedirect('{loginfailed}'.format(loginfailed = login_failed_url))

    access_token_uri = 'https://accounts.google.com/o/oauth2/token'
    redirect_uri = "http://mysite/login/google/auth"
    params = urllib.urlencode({
        'code':request.GET['code'],
        'redirect_uri':redirect_uri,
        'client_id':XXXXX_your_google_key,
        'client_secret':XXXXX_your_google_secret,
        'grant_type':'authorization_code'
    })
    headers={'content-type':'application/x-www-form-urlencoded'}
    resp, content = parser.request(access_token_uri, method = 'POST', body = params, headers = headers)
    token_data = jsonDecode(content)
    resp, content = parser.request("https://www.googleapis.com/oauth2/v1/userinfo?access_token={accessToken}".format(accessToken=token_data['access_token']))
    #this gets the google profile!!
    google_profile = jsonDecode(content)
    #log the user in-->
    #HERE YOU LOG THE USER IN, OR ANYTHING ELSE YOU WANT
    #THEN REDIRECT TO PROTECTED PAGE
    return HttpResponseRedirect('/dashboard')

I really hope this helps people out there, and saves them the hours I wasted. Comments on the code are more than welcome!