This plugin is a Rails3 alternative of the plugin called acts_as_follower by tcocca. It allows any model to follow other models and a model can be followed by other models.
Usually you will use this plugin when implementing a blog-style website where users will follow other users or for users to follow Books, etc…
Add this line to your Gemfile (and run bundle install):
Run the generator which will generate a migration file.
rails g acts_as_followable rake db:migrate
The plugin comes with a Follow model file. You can extend the default model by creating the app/models/follow.rb file with content.
class Follow ... your extension here ... end
If you would like a model to follow or to be followed by any other model, just add the mixin:
class User < ActiveRecord::Base ... acts_as_followable ... end
To have an object start following another use the following:
book = Book.find(1) user = User.find(1) user.follow(book)
To stop following an object use the following:
You can remove all the followers/followings like this:
You can check to see if an object is following another object through the following:
You can check to see if an object is followed by another object through the following:
To get a list of followers by a given type use the following (e.g. list of users that follow a book):
User.following(book) or book.followers_by_type('User') or book.user_followers # Also User.following(book).order('name').limit(2) or book.followers_by_type('User').limit(2) or book.user_followers.order('name')
To get a list of records of a particular type which this record is following (e.g. list of books followed by a user)
Book.followed_by(user) or user.following_by_type('Book') or user.following_book # Also Book.followed_by(user).order('title').limit(2) or user.following_by_type('Book').limit(2) or user.following_book('title')
You can also query Follow model records like this:
# What user is following user.follows user.follows.limit(1) # Who follows a book book.followings book.followings.order('created_at') # Follow records by follower type Follow.for_follower_type('User') Follow.for_follower_type('User').limit(1) # Follow records by followable type Follow.for_followable_type('Book') Follow.for_followable_type('Book').order('created_at') # Follow records from follower Follow.for_follower(user) Follow.for_follower(user).limit(1) # Follow records from followable Follow.for_followable(book) Follow.for_followable(book).order('created_at')