Class: ActiveSupport::Notifications::Fanout

Inherits:
Object
  • Object
show all
Includes:
Mutex_m
Defined in:
lib/active_support/notifications/fanout.rb

Overview

This is a default queue implementation that ships with Notifications. It just pushes events to all registered log subscribers.

This class is thread safe. All methods are reentrant.

Defined Under Namespace

Modules: Subscribers

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Fanout

Returns a new instance of Fanout.



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# File 'lib/active_support/notifications/fanout.rb', line 13

def initialize
  @subscribers = []
  @listeners_for = ThreadSafe::Cache.new
  super
end

Instance Method Details

#finish(name, id, payload) ⇒ Object 



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# File 'lib/active_support/notifications/fanout.rb', line 39

def finish(name, id, payload)
  listeners_for(name).each { |s| s.finish(name, id, payload) }
end

#listeners_for(name) ⇒ Object 



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# File 'lib/active_support/notifications/fanout.rb', line 47

def listeners_for(name)
  # this is correctly done double-checked locking (ThreadSafe::Cache's lookups have volatile semantics)
  @listeners_for[name] || synchronize do
    # use synchronisation when accessing @subscribers
    @listeners_for[name] ||= @subscribers.select { |s| s.subscribed_to?(name) }
  end
end

#listening?(name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_support/notifications/fanout.rb', line 55

def listening?(name)
  listeners_for(name).any?
end

#publish(name, *args) ⇒ Object 



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# File 'lib/active_support/notifications/fanout.rb', line 43

def publish(name, *args)
  listeners_for(name).each { |s| s.publish(name, *args) }
end

#start(name, id, payload) ⇒ Object 



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# File 'lib/active_support/notifications/fanout.rb', line 35

def start(name, id, payload)
  listeners_for(name).each { |s| s.start(name, id, payload) }
end

#subscribe(pattern = nil, block = Proc.new) ⇒ Object 



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# File 'lib/active_support/notifications/fanout.rb', line 19

def subscribe(pattern = nil, block = Proc.new)
  subscriber = Subscribers.new pattern, block
  synchronize do
    @subscribers << subscriber
    @listeners_for.clear
  end
  subscriber
end

#unsubscribe(subscriber) ⇒ Object 



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# File 'lib/active_support/notifications/fanout.rb', line 28

def unsubscribe(subscriber)
  synchronize do
    @subscribers.reject! { |s| s.matches?(subscriber) }
    @listeners_for.clear
  end
end

#wait ⇒ Object

This is a sync queue, so there is no waiting.



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# File 'lib/active_support/notifications/fanout.rb', line 60

def wait
end