Acts as Readable - Drop-in 'mark as read' functionality

When writing an application there’s a number of times where it can be very useful to know whether or not a user has seen or accessed a piece of information. I recently had to write a solution to such a need and have wrapped up the result in a plugin for your enjoyment.

ActsAsReadable allows you to create a generic relationship of items which can be marked as ‘read’ by users. This is useful for forums or any other kind of situation where you might need to know whether or not a user has seen a particular model.


To install the plugin just install from the GitHub repository:

git clone git:// vendor/plugins/acts_as_readable

You will need the readings table to use this plugin. A generator has been included,
simply type

script/generate acts_as_readable_migration

to get the standard migration created for you.


class Post < ActiveRecord::Base
bob = User.find_by_name("bob")

bob.readings                      # => []

Post.find_unread_by(bob)          # => [<Post 1>,<Post 2>,<Post 3>...]
Post.find_read_by(bob)            # => []

Post.find(1).read_by?(bob)        # => false
Post.find(1).read_by!(bob)        # => <Reading 1>
Post.find(1).read_by?(bob)        # => true
Post.find(1).users_who_read       # => [<User bob>]

Post.find_unread_by(bob)          # => [<Post 2>,<Post 3>...]
Post.find_read_by(bob)            # => [<Post 1>]

bob.readings                      # => [<Reading 1>]

And that’s all there is to it! It’s not an incredibly complex set of features, but I find it to be a pretty useful one. If you have any questions or issues, please feel free to post them on the public Trac