How to create Django like button for anonymous users?

Question

I am using Django and my website has no user profiles so all are anonymous. I want to implement a \'like\' system. How do I restrict a user to like only once. Thanks.

Answer 1

You can't 100% restrict multiple votes, but you can make it very difficult for a regular user, by using:

• a cookie
• a DB entry with the voter's IP

Answer 2

Facebook seems to track uniqueness of likes when its tied to a facebook app though the XFBML script. Regardless of whether I'm logged in or logged out of facebook, the like button seems to recognize that I've already voted.

• Creating a facebook app can currently be done here: https://developers.facebook.com/apps
• An interesting feature of facebooks apps is facebook insights, which can be found here: http://www.facebook.com/insights/
• Supporting documentation for facebook insights can be found here: http://developers.facebook.com/docs/insights/

While still in its infancy, there is a project called django-like-button which provides a wrapper for facebooks XFBML like button. If you're using pip and virtualenv, you can pip install django-like-button and follow the readme.rst installation instructions. The project can be found on github.

Answer 3

If you don't have any way of identifying your users then your best bet is to store this info in a browser cookie or HTML5 local storage. (I don't advise using flash cookies since there is a long debate about them and they are harder to implement)