Synnefo

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

import oauth2 as oauth

import urlparse

from django.http import HttpResponse

from django.utils import simplejson as json

from django.contrib import messages

from astakos.im.util import get_context, prepare_response

from astakos.im.models import AstakosUser, Invitation

from astakos.im.views import render_response, requires_anonymous

from astakos.im.forms import LocalUserCreationForm, ThirdPartyUserCreationForm

from astakos.im.faults import BadRequest

from astakos.im.backends import get_backend

from astakos.im.settings import TWITTER_KEY, TWITTER_SECRET, INVITATIONS_ENABLED, IM_MODULES

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

# OAuth secret into your project's settings. 

consumer = oauth.Consumer(TWITTER_KEY, 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, 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, login_template='im/login.html', on_signup_failure='im/signup.html', on_signup_success='im/signup_complete.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')

    if email: # signup mode

        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, on_signup_failure, on_signup_success, extra_context)

        else:

            status = messages.ERROR

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

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

            prefix = 'Invited' if request.session['invitation_code'] else ''

            suffix  = 'UserCreationForm'

            for provider in IM_MODULES:

                main = provider.capitalize() if provider == 'local' else 'ThirdParty'

                formclass = '%s%s%s' % (prefix, main, suffix)

                extra_context['%s_form' % provider] = globals()[formclass]()

            return render_response(on_signup_failure,

                                   context_instance=get_context(request, extra_context))

    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:

            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(login_template,

                   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

def create_user(request, form, backend=None, post_data={}, next = None, on_failure='im/signup.html', on_success='im/signup_complete.html', extra_context={}): 

    """

    Create a user.

    The user activation will be delegated to the backend specified by the ``backend`` keyword argument

    if present, otherwise to the ``astakos.im.backends.InvitationBackend``

    if settings.ASTAKOS_INVITATIONS_ENABLED is True or ``astakos.im.backends.SimpleBackend`` if not

    (see backends);

    Upon successful user creation if ``next`` url parameter is present the user is redirected there

    otherwise renders the ``on_success`` template (if exists) or im/signup_complete.html.

    On unsuccessful creation, renders the ``on_failure`` template (if exists) or im/signup.html with an error message.

    **Arguments**

    ``on_failure``

        A custom template to render in case of failure. This is optional;

        if not specified, this will default to ``im/signup.html``.

    ``on_success``

        A custom template to render in case of success. This is optional;

        if not specified, this will default to ``im/signup_complete.html``.

    ``extra_context``

        An dictionary of variables to add to the template context.

    **Template:**

    im/signup.html or ``on_failure`` keyword argument.

    im/signup_complete.html or ``on_success`` keyword argument.

    """

    try:

        if not backend:

            backend = get_backend(request)

        if form.is_valid():

            status, message, user = backend.signup(form)

            if status == messages.SUCCESS:

                for k,v in post_data.items():

                    setattr(user,k, v)

                user.save()

                if user.is_active:

                    return prepare_response(request, user, next=next)

            messages.add_message(request, status, message)

            return render_response(on_success,

                                   context_instance=get_context(request, extra_context))

        else:

            messages.add_message(request, messages.ERROR, form.errors)

    except (Invitation.DoesNotExist, ValueError), e:

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

    for provider in IM_MODULES:

        extra_context['%s_form' % provider] = backend.get_signup_form(provider)

    return render_response(on_failure,

                           form = LocalUserCreationForm(),

                           context_instance=get_context(request, extra_context))