Python Twitter + django-social-auth == Hello New User

I have been experimenting with the twitter module for Python and decided to combine it with django-social-auth to welcome new users who join Difio. In this post I will show you how to tweet on behalf of the user when they join your site and send them a welcome email.

Configuration

In django-social-auth the authentication workflow is handled by an operations pipeline where custom functions can be added or default items can be removed to provide custom behavior. This is how our pipeline looks:

settings.py

SOCIAL_AUTH_PIPELINE = (
    'social_auth.backends.pipeline.social.social_auth_user',
    #'social_auth.backends.pipeline.associate.associate_by_email',
    'social_auth.backends.pipeline.user.get_username',
    'social_auth.backends.pipeline.user.create_user',
    'social_auth.backends.pipeline.social.associate_user',
    'social_auth.backends.pipeline.social.load_extra_data',
    'social_auth.backends.pipeline.user.update_user_details',
    'myproject.tasks.welcome_new_user'
)

This is the default plus an additional method at the end to welcome new users.

You also have to create and configure a Twitter application so that users can login with Twitter OAuth to your site. RTFM for more information on how to do this.

Custom pipeline actions

This is how the custom pipeline action should look:

myproject/tasks.py

from urlparse import parse_qs

def welcome_new_user(backend, user, social_user, is_new=False, new_association=False, *args, **kwargs):
    """
        Part of SOCIAL_AUTH_PIPELINE. Works with django-social-auth==0.7.21 or newer
        @backend - social_auth.backends.twitter.TwitterBackend (or other) object
        @user - User (if is_new) or django.utils.functional.SimpleLazyObject (if new_association)
        @social_user - UserSocialAuth object
    """
    if is_new:
        send_welcome_email.delay(user.email, user.first_name)

    if backend.name == 'twitter':
        if is_new or new_association:
            access_token = social_user.extra_data['access_token']
            parsed_tokens = parse_qs(access_token)
            oauth_token = parsed_tokens['oauth_token'][0]
            oauth_secret = parsed_tokens['oauth_token_secret'][0]
            tweet_on_join.delay(oauth_token, oauth_secret)

    return None

This code works with django-social-auth==0.7.21 or newer. In older versions the new_association parameter is missing as I discovered. If you use an older version you won't be able to distinguish between newly created accounts and ones which have associated another OAuth backend. You are warned!

Tweet & email

Sending the welcome email is out of the scope of this post. I am using django-templated-email to define how emails look and sending them via Amazon SES. See Email Logging for Django on RedHat OpenShift With Amazon SES for more information on how to configure emailing with SES.

Here is how the Twitter code looks:

myproject/tasks.py

import twitter
from celery.task import task
from settings import TWITTER_CONSUMER_KEY, TWITTER_CONSUMER_SECRET

@task
def tweet_on_join(oauth_token, oauth_secret):
    """
        Tweet when the user is logged in for the first time or
        when new Twitter account is associated.

        @oauth_token - string
        @oauth_secret - string
    """
    t = twitter.Twitter(
            auth=twitter.OAuth(
                oauth_token, oauth_secret,
                TWITTER_CONSUMER_KEY, TWITTER_CONSUMER_SECRET
            )
        )
    t.statuses.update(status='Started following open source changes at http://www.dif.io!')

This will post a new tweet on behalf of the user, telling everyone they joined your website!

NOTE: tweet_on_join and send_welcome_email are Celery tasks, not ordinary Python functions. This has the advantage of being able to execute these actions async and not slow down the user interface.

Are you doing something special when a user joins your website? Please share your comments below. Thanks!

Configuration

Custom pipeline actions

Tweet & email

Comments !