Method: AMQP::Channel#default_exchange

Defined in:
lib/amqp/channel.rb

#default_exchange ⇒ Exchange

Returns exchange object with the same name as default (aka unnamed) exchange. Default exchange is a direct exchange and automatically routes messages to queues when routing key matches queue name exactly. This feature is known as “automatic binding” (of queues to default exchange).

Use default exchange when you want to route messages directly to specific queues (queue names are known, you don’t mind this kind of coupling between applications).

Examples:

Using default exchange to publish messages to queues with known names

AMQP.start(:host => 'localhost') do |connection|
  ch        = AMQP::Channel.new(connection)

  queue1    = ch.queue("queue1").subscribe do |payload|
    puts "[#{queue1.name}] => #{payload}"
  end
  queue2    = ch.queue("queue2").subscribe do |payload|
    puts "[#{queue2.name}] => #{payload}"
  end
  queue3    = ch.queue("queue3").subscribe do |payload|
    puts "[#{queue3.name}] => #{payload}"
  end
  queues    = [queue1, queue2, queue3]

  # Rely on default direct exchange binding, see section 2.1.2.4 Automatic Mode in AMQP 0.9.1 spec.
  exchange = AMQP::Exchange.default
  EM.add_periodic_timer(1) do
    q = queues.sample

    exchange.publish "Some payload from #{Time.now.to_i}", :routing_key => q.name
  end
end

Returns:

See Also:



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# File 'lib/amqp/channel.rb', line 491

def default_exchange
  @default_exchange ||= Exchange.default(self)
end