ActiveRecord::Publishable

Publish changes to your ActiveRecord models to Redis for use with PubSub. This allows you to easily implement Server-Sent events.

Add this line to your application's Gemfile:

gem 'activerecord-publishable'

And then execute:

$ bundle

Or install it yourself as:

$ gem install activerecord-publishable

To start publishing changes to your models, include the module and call publishable.

class Post < ActiveRecord::Base
  include ActiveRecord::Publishable

  publishable
end

The publishable method creates an after_commit hook on create, update, and destroy. You can pass the :on option to only push certain events. It accepts all of the options you can pass to an after_commit hook, like :if and :unless.

publishable on: [:update, :destroy]
publishable on: :create, if: :some_condition?
publishable on: :create, unless: ->{ dont_push? }

When pushing to Redis, your model will be serialized as JSON. If you have ActiveModel::Serializers loaded, your serializer will be looked up. Otherwise, as_json will be used.

You can pass options for serialization by using the :serialize option. The :with option allows you to override the serializer that is used.

publishable serialize: { with: OtherPostSerializer }
publishable serialize: { only: [:title, :content] }

By default, events will be published to <collection>:create, <collection>:update, and <collection>:destroy, where collection is the plural name of your model. To override this behavior, you can pass the :channel option:

publishable on: :create, channel: "custom:create"

Alternatively, you can override channel_for_publishing:

class Post < ActiveRecord::Base
  include ActiveRecord::Publishable

  publishable

  def channel_for_publishing(action)
    "posts:#{user.id}:#{action}"
  end
end

The demo app provides an example of streaming changes to your models using Server-Sent events.

1. Clone the repository
2. Run bundle install
3. Run rake example
4. Open your browser to localhost:4567

1. Fork it ( https://github.com/rzane/activerecord-publishable/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request