ActsAsJuggerSource¶ ↑

This plugins provides an “acts_as_jugger_source“ method for all ActiveRecord’s models. When you declare a model as a jugger source, then whenever, you change, create or destroy an instance of a model a notification will be sent to Juggernaut.

Sample usage¶ ↑

The basic use of this plugins is like this:

class MyModel < ActiveRecord::Base
  acts_as_jugger_source
end

Whenever you create, save or destroy an instance of this model a notification to the channel ‘MyModel’ of Juggernaut will be sent.

Customizing the channel name¶ ↑

By default, acts_as_jugger_source will sent notifications to the channel with the same name as the model. This means that:

model = MyModel.new
model.save!

Will sent notifications to the channel named “MyModel”. This can be overrided with the “:channel“ option:

class Somemodel < ActiveRecord::Base
  acts_as_jugger_source :channel => 'some-deliverate-channel'
end

Notifications received by a Juggernaut subscriber (mostly a browser) with contain a payload with three attributes:

• “operation“, which will be either “save”, “create” or “destroy”,

• “model“, which will be the name of the model class; and

• “instance“, which will constain a shallow copy (created with the to_json method) of the model instance.

Sending the desired notifications¶ ↑

By default, acts_as_jugger_source will emit notifications for after_save after_create and after_destroy events. You may select the desired events with the “operations“ options:

class Somemodel
  acts_as_jugger_source :operations => [:save, :destroy]
end

Advanced features¶ ↑

You can provide a block to the acts_as_jugger_source method. This block will be invoked with three arguments:

• Opertation, which is either :save, :create or :destroy.

• The Model class.

• The model instance.

If the block returns a value it must be a Hash with an :operation, :model, and :instance keys. If any of these are omitted, the corresponding argument will be used; then this value will be used to build the payload for the notification.

The result could be also a list of hashes. The hashes should have the same format as the single Hash described above. When the block returns this list, then this plugin will emmit several notifications to Juggernaut.

Cascade notifications¶ ↑

Sometimes you may want to emit several ‘cascading’ notifications when a model changes.

For instance you have a Issue model that belongs to a Project. You want that whenever a Issue is saved, the Project which it belongs to should be notified:

class Issue
  acts_as_jugger_source :channel => 'musqueteers' do |o, m, i|
    result = [build_jugger_event(o, m, i)]
    result << build_jugger_event(:save, Project, i.project) if i.project
  end
end

Notice that both notifications are sent to the same channel!

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