has_comments

Instalation

1) Install the plugin with script/plugin install git://github.com/fnando/has_comments.git

2) Generate a migration with script/generate migration create_comments and add the following code:

class CreateComments < ActiveRecord::Migration
  def self.up
    create_table :comments do |t|
      t.text :comment
      t.references :commentable, :polymorphic => true
      t.references :user
      t.timestamps
    end

    add_index :comments, :commentable_type
    add_index :comments, :commentable_id
    add_index :comments, :user_id
  end

  def self.down
    drop_table :comments
  end
end

3) Run the migrations with rake db:migrate

Usage

1) Add the method call has_comments to your model.

class Photo < ActiveRecord::Base
  has_comments
end

2) Add this association on your User model:

class User < ActiveRecord::Base
  has_many :comments, :dependent => :destroy
end

photo = Photo.find(:first)
user = User.find(:first)

photo.comment(:user => user, :comment => 'Wow! Nice shot!') # => <comment>
photo.comments # => [<comment>]
photo.find_users_that_commented # => [<user>]
photo.find_comments_by_user(user) # => [<comment>]

NOTE: You should have a User model. You should also have a comments_count column on your model. Otherwise, this won't work!

Copyright (c) 2008 Nando Vieira, released under the MIT license