Wisper::Activerecord::Publisher

Extract logic from your callbacks into wisper listeners for model events (create, update, delete)

Installation

Add this line to your application's Gemfile:

gem 'wisper-activerecord-publisher'

And then execute:

$ bundle

Usage

Create a wisper listener with methods named to match any of the supported broadcast events:

• MODEL_created - event is published after record created in DB
• MODEL_updated - event is published after record is updated and includes attributes that changed
• MODEL_destroyed - event is published after record is destroyed and includes a read-only copy of the model attributes

This gem does support background event processing since the events are published after commit and each event includes the necessary payload (ie: changes).

Example

class Foo < ActiveRecord::Base
end

class MyListener
  def foo_created(model)
    # do something here with the model
  end

  def foo_updated(model, changes)
  end

  def foo_destroyed(model_attributes)
    # read-only copy of attributes
    # model is already deleted from database
  end
end

Limiting events per model

Rather than have a model broadcast all events, you can limit them using the broadcast_on method.

class Foo < ActiveRecord::Base
  broadcast_on :create
end

class MyListener
  def foo_created(model)
    # do something here with the model
  end

  def foo_updated(model, changes)
    # Will not be called
  end

  def foo_destroyed(model_attributes)
    # Will not be called
  end
end

Changing default event broadcasts

You can turn off or limit broadcasts for all models in your application via an initializer.

# config/initializers/wisper_activerecord_publisher.rb

Wisper::ActiveRecord::Publisher.configure do |config|
  config.default_broadcast_events = [:create, :update] # Only broadcast create and update events
end

Additionally, you can disable all broadcasts in a model by calling disable_all_lifecycle_broadcasts! on the model class.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/betterup/wisper-activerecord-publisher.