RabbitMQ: Alternate Exchange

Alternate Exchange is used to catch “unrouted” message.

1. Create an exchange called dlx with the type fanout. We choose fanout to catch any routing keys.
2. Create a queue called dlq and bind it with dlx.
3. Create an exchange called foo and set it’s alternate_exchange = dlx.
4. Send message to foo. Since foo is not bound with any queue, by default, the message is lost. But since we set the alternate_exchange in step 3, the message is sent to dlx which after that redirected to dlq.

channel.assertExchange('foo', 'fanout', {
  alternateExchange: 'dlx'
})

References:

• https://www.rabbitmq.com/docs/ae