Synnefo

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# This is based on the docs at: https://github.com/simplegeo/python-oauth2

import oauth2 as oauth

import urlparse

import  traceback

from django.conf import settings

from django.http import HttpResponse

from django.utils import simplejson as json

from django.contrib.auth import authenticate

from django.contrib import messages

from django.shortcuts import redirect

from astakos.im.target.util import prepare_response, requires_anonymous

from astakos.im.util import get_or_create_user, get_context

from astakos.im.models import AstakosUser, Invitation

from astakos.im.views import render_response, create_user

from astakos.im.backends import get_backend

from astakos.im.forms import LocalUserCreationForm, ThirdPartyUserCreationForm

from astakos.im.faults import BadRequest

# It's probably a good idea to put your consumer's OAuth token and

# OAuth secret into your project's settings. 

consumer = oauth.Consumer(settings.TWITTER_KEY, settings.TWITTER_SECRET)

client = oauth.Client(consumer)

request_token_url = 'http://twitter.com/oauth/request_token'

access_token_url = 'http://twitter.com/oauth/access_token'

# This is the slightly different URL used to authenticate/authorize.

authenticate_url = 'http://twitter.com/oauth/authenticate'

@requires_anonymous

def login(request, template_name='signup.html', extra_context={}):

    # store invitation code and email

    request.session['email'] = request.GET.get('email')

    request.session['invitation_code'] = request.GET.get('code')

    # Step 1. Get a request token from Twitter.

    resp, content = client.request(request_token_url, "GET")

    if resp['status'] != '200':

        raise Exception("Invalid response from Twitter.")

    request_token = dict(urlparse.parse_qsl(content))

    if request.GET.get('next'):

        request_token['next'] = request.GET['next']

    # Step 2. Store the request token in a session for later use.

    response = HttpResponse()

    request.session['Twitter-Request-Token'] = value=json.dumps(request_token)

    # Step 3. Redirect the user to the authentication URL.

    url = "%s?oauth_token=%s" % (authenticate_url, request_token['oauth_token'])

    response['Location'] = url

    response.status_code = 302

    return response

@requires_anonymous

def authenticated(request, backend=None, template_name='login.html', extra_context={}):

    # Step 1. Use the request token in the session to build a new client.

    data = request.session.get('Twitter-Request-Token')

    if not data:

        raise Exception("Request token cookie not found.")

    del request.session['Twitter-Request-Token']

    request_token = json.loads(data)

    if not hasattr(request_token, '__getitem__'):

        raise BadRequest('Invalid data formating')

    try:

        token = oauth.Token(request_token['oauth_token'],

                            request_token['oauth_token_secret'])

    except:

        raise BadRequest('Invalid request token cookie formatting')

    client = oauth.Client(consumer, token)

    # Step 2. Request the authorized access token from Twitter.

    resp, content = client.request(access_token_url, "GET")

    if resp['status'] != '200':

        raise Exception("Invalid response from Twitter.")

    """

    This is what you'll get back from Twitter. Note that it includes the

    user's user_id and screen_name.

    {

        'oauth_token_secret': 'IcJXPiJh8be3BjDWW50uCY31chyhsMHEhqJVsphC3M',

        'user_id': '120889797', 

        'oauth_token': '120889797-H5zNnM3qE0iFoTTpNEHIz3noL9FKzXiOxwtnyVOD',

        'screen_name': 'heyismysiteup'

    }

    """

    access_token = dict(urlparse.parse_qsl(content))

    # Step 3. Lookup the user or create them if they don't exist.

    # When creating the user I just use their screen_name@twitter.com

    # 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.

    screen_name = access_token['screen_name']

    next = request_token.get('next')

    # check first if user with that email is registered

    # and if not create one

    user = None

    email = request.session.pop('email')

    # signup mode

    if email:

        if not reserved_screen_name(screen_name): 

            try:

                user = AstakosUser.objects.get(email = email)

            except AstakosUser.DoesNotExist, e:

                # register a new user

                post_data = {'provider':'Twitter', 'affiliation':'twitter',

                                'third_party_identifier':screen_name}

                form = ThirdPartyUserCreationForm({'email':email})

                return create_user(request, form, backend, post_data, next, template_name, extra_context)

        else:

            status = messages.ERROR

            message = '%s@twitter is already registered' % screen_name

            messages.add_message(request, messages.ERROR, message)

    else:

        # login mode

        try:

            user = AstakosUser.objects.get(third_party_identifier = screen_name,

                                           provider = 'Twitter')

        except AstakosUser.DoesNotExist:

            messages.add_message(request, messages.ERROR, 'Not registered user')

        if user and user.is_active:

            #in order to login the user we must call authenticate first

            user = authenticate(email=user.email, auth_token=user.auth_token)

            return prepare_response(request, user, next)

        elif user and not user.is_active:

            messages.add_message(request, messages.ERROR, 'Inactive account: %s' % user.email)

    return render_response(template_name,

                   form = LocalUserCreationForm(),

                   context_instance=get_context(request, extra_context))

def reserved_screen_name(screen_name):

    try:

        AstakosUser.objects.get(provider='Twitter',

                                third_party_identifier=screen_name)

        return True

    except AstakosUser.DoesNotExist, e:

        return False