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.

Namespace

Module

Class

Methods

Included Modules

  • Mutex_m

Class Public methods

new()

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 54
      def initialize
        @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
        super
      end
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Instance Public methods

all_listeners_for(name)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 301
      def all_listeners_for(name)
        # this is correctly done double-checked locking (Concurrent::Map's lookups have volatile semantics)
        @all_listeners_for[name] || synchronize do
          # use synchronisation when accessing @subscribers
          @all_listeners_for[name] ||=
            @string_subscribers[name] + @other_subscribers.select { |s| s.subscribed_to?(name) }
        end
      end
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build_handle(name, id, payload)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 276
      def build_handle(name, id, payload)
        Handle.new(self, name, id, payload)
      end
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finish(name, id, payload, listeners = nil)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 287
      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
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listeners_for(name)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 310
      def listeners_for(name)
        all_listeners_for(name).reject { |s| s.silenced?(name) }
      end
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listening?(name)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 314
      def listening?(name)
        all_listeners_for(name).any? { |s| !s.silenced?(name) }
      end
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publish(name, *args)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 293
      def publish(name, *args)
        iterate_guarding_exceptions(listeners_for(name)) { |s| s.publish(name, *args) }
      end
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publish_event(event)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 297
      def publish_event(event)
        iterate_guarding_exceptions(listeners_for(event.name)) { |s| s.publish_event(event) }
      end
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start(name, id, payload)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 280
      def start(name, id, payload)
        handle_stack = (IsolatedExecutionState[:_fanout_handle_stack] ||= [])
        handle = build_handle(name, id, payload)
        handle_stack << handle
        handle.start
      end
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subscribe(pattern = nil, callable = nil, monotonic: false, &block)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 68
      def subscribe(pattern = nil, callable = nil, monotonic: false, &block)
        subscriber = Subscribers.new(pattern, callable || block, monotonic)
        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
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unsubscribe(subscriber_or_name)

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 85
      def unsubscribe(subscriber_or_name)
        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
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wait()

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

📝 Source code 
# File activesupport/lib/active_support/notifications/fanout.rb, line 319
      def wait
      end
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