Skip to Content Skip to Search

class ActiveSupport::Notifications::Fanout

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.

Public class methods

Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 50
def initialize
  @mutex = Mutex.new
  @string_subscribers = Concurrent::Map.new { |h, k| h.compute_if_absent(k) { [] } }
  @other_subscribers = []
  @all_listeners_for = Concurrent::Map.new
  @groups_for = Concurrent::Map.new
  @silenceable_groups_for = Concurrent::Map.new
end

Public instance methods

Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 297
def all_listeners_for(name)
  # this is correctly done double-checked locking (Concurrent::Map's lookups have volatile semantics)
  @all_listeners_for[name] || @mutex.synchronize do
    # use synchronisation when accessing @subscribers
    @all_listeners_for[name] ||=
      @string_subscribers[name] + @other_subscribers.select { |s| s.subscribed_to?(name) }
  end
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 272
def build_handle(name, id, payload)
  Handle.new(self, name, id, payload)
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 283
def finish(name, id, payload, listeners = nil)
  handle_stack = IsolatedExecutionState[:_fanout_handle_stack]
  handle = handle_stack.pop
  handle.finish_with_values(name, id, payload)
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 306
def listeners_for(name)
  all_listeners_for(name).reject { |s| s.silenced?(name) }
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 310
def listening?(name)
  all_listeners_for(name).any? { |s| !s.silenced?(name) }
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 289
def publish(name, *args)
  iterate_guarding_exceptions(listeners_for(name)) { |s| s.publish(name, *args) }
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 293
def publish_event(event)
  iterate_guarding_exceptions(listeners_for(event.name)) { |s| s.publish_event(event) }
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 276
def start(name, id, payload)
  handle_stack = (IsolatedExecutionState[:_fanout_handle_stack] ||= [])
  handle = build_handle(name, id, payload)
  handle_stack << handle
  handle.start
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 64
def subscribe(pattern = nil, callable = nil, monotonic: false, &block)
  subscriber = Subscribers.new(pattern, callable || block, monotonic)
  @mutex.synchronize do
    case pattern
    when String
      @string_subscribers[pattern] << subscriber
      clear_cache(pattern)
    when NilClass, Regexp
      @other_subscribers << subscriber
      clear_cache
    else
      raise ArgumentError,  "pattern must be specified as a String, Regexp or empty"
    end
  end
  subscriber
end
Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 81
def unsubscribe(subscriber_or_name)
  @mutex.synchronize do
    case subscriber_or_name
    when String
      @string_subscribers[subscriber_or_name].clear
      clear_cache(subscriber_or_name)
      @other_subscribers.each { |sub| sub.unsubscribe!(subscriber_or_name) }
    else
      pattern = subscriber_or_name.try(:pattern)
      if String === pattern
        @string_subscribers[pattern].delete(subscriber_or_name)
        clear_cache(pattern)
      else
        @other_subscribers.delete(subscriber_or_name)
        clear_cache
      end
    end
  end
end

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

Source code GitHub
# File activesupport/lib/active_support/notifications/fanout.rb, line 315
def wait
end

Namespace

Definition files