ChalkDust

ChalkDust can be used to build activty feeds such as followings and friendships by allowing models to subscribe to activity feeds published by other models.

Every time an activity occurs it is copied to all subscribers of the target of that activity. This creates an activty feed per subscriber (more data) which scales better and allows additional features such as feed to delete/hide activity items.

Code Climate Build Status

Installation

Add this line to your application's Gemfile:

gem 'chalk_dust'

ChalkDust has a dependency on ActiveRecord and a soft dependency on Rails. If you are using Rails you can install the migrations as follows:

rails generate chalk_dust:install_migrations

Usage

Subscribing

A subscription connects two objects, e.g "Sam" follows "My first blog post"

ChalkDust.subscribe(user, :to => post)

ChalkDust.subscribers_of(post) # => [user, post]

Self-subscribing

Typically you will want to self-subscribe models on creation to themseleves so an activity feed is built for the model itself.

ChalkDust.self_subscribe(user)
# or
ChalkDust.subscribe(user, :to => user)

Undirected subscriptions

All subscriptions are directed. You can create a two way subscription, e.g a friendship, as follows:

ChalkDust.subscribe(bob, :to => alice, :undirected => true)
# or
ChalkDust.subscribe(bob,   :to => alice)
ChalkDust.subscribe(alice, :to => bob)

Publishing activity

Describes an event where X (performer) did Y (activity) to Z (target).

ChalkDust.publish_event(user, 'added', comment)

If the activity should be published to the feed of an object other than the target then it can be either be passed as an additional argument or provided as a method called activity_root.

ChalkDust.publish_event(user, 'added', comment, :root => comment.post)

or

(TODO)

class Comment < ActiveRecord::Base
  belongs_to :post

  def activity_root
    post
  end
end

Activity Feeds

ChalkDust.activity_feed_for(user, :since => 2.weeks.ago)
ChalkDust.activity_feed_for(post, :since => 2.weeks.ago)

Contributing

Contributions welcome, please fork and send a pull request.

Thanks

Thanks to Igor @ Lifetrip Limited for allowing this code to be open sourced.

License

Copyright (c) 2013 Lifetrip Limited

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.