Class: ActiveRecord::PostgresPubSub::Listener

Inherits:
Object
  • Object
show all
Extended by:
PrivateAttr
Defined in:
lib/activerecord/postgres_pub_sub/listener.rb

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(channel, listen_timeout: nil, exclusive_lock: true, notify_only: true) ⇒ Listener

Returns a new instance of Listener.



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# File 'lib/activerecord/postgres_pub_sub/listener.rb', line 23

def initialize(channel, listen_timeout: nil, exclusive_lock: true, notify_only: true)
  @channel = channel
  @listen_timeout = listen_timeout
  @exclusive_lock = exclusive_lock
  @notify_only = notify_only
end

Class Method Details

.listen(channel, listen_timeout: nil, exclusive_lock: true, notify_only: true) {|listener| ... } ⇒ Object

Yields:

  • (listener) 


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# File 'lib/activerecord/postgres_pub_sub/listener.rb', line 14

def self.listen(channel, listen_timeout: nil, exclusive_lock: true, notify_only: true)
  listener = new(channel,
                 listen_timeout: listen_timeout,
                 exclusive_lock: exclusive_lock,
                 notify_only: notify_only)
  yield(listener) if block_given?
  listener.listen
end

Instance Method Details

#listen ⇒ Object 



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# File 'lib/activerecord/postgres_pub_sub/listener.rb', line 42

def listen
  with_connection do |connection|
    on_start_blk&.call

    loop do
      wait_for_notify(connection) do |payload|
        notify_only ? on_notify_blk.call : on_notify_blk.call(payload)
      end
    end
  end
end

#on_notify(&blk) ⇒ Object 



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# File 'lib/activerecord/postgres_pub_sub/listener.rb', line 30

def on_notify(&blk)
  @on_notify_blk = blk
end

#on_start(&blk) ⇒ Object 



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# File 'lib/activerecord/postgres_pub_sub/listener.rb', line 34

def on_start(&blk)
  @on_start_blk = blk
end

#on_timeout(&blk) ⇒ Object 



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# File 'lib/activerecord/postgres_pub_sub/listener.rb', line 38

def on_timeout(&blk)
  @on_timeout_blk = blk
end