Question

I want to add a “like” functionality to a blog I am creating in Ruby on Rails to let people “thumbs up” a post. Then I would like to be able to display the most liked posts in the side bar. I am new to rails so rely heavily on tutorials and stack overflow. Any good resources or what is this even called. I assumed “voting” for this question.

Answer 1

You should look up link_to_remote and using AJAX with rails. Here is a nice tutorial to get started: http://railsonedge.blogspot.com/2008/03/tutorial-beginning-ajax-with-rails-20.html

The idea would be:

• The user clicks on “vote”

• It sends an asynchronous message to the controller to save the vote. (use link_to_remote)

• the :complete callback does something (eg “thanks for voting!”)

• the :update changes the voting zone (eg “voted. 6 votes on this”)

There are a lot of tutorials on the subject.

---

EDIT: I wrote that a while ago and since then the best practices have changed. Now please take a look at how to do that using unobstrusive javascript. Good resources include Ryan Bates Bates’s railscast #205 and the wikipedia article to understand the principle.

“Unobtrusive JavaScript” is an
emerging technique in the JavaScript
programming language, as used on the
World Wide Web. Though the term is not
formally defined, its basic principles
are generally understood to include:

• Separation of functionality (the
  “behavior layer”) from a Web page’s
  structure/content and presentation

• Best practices to avoid the problems
  of traditional JavaScript programming
  (such as browser inconsistencies and
  lack of scalability)

• Progressive enhancement to support
  user agents that may not support
  advanced JavaScript functionality[