Search code examples
node.jsrabbitmqamqp

AMQP RabbitMQ get missed published messages

When using send/listen which is 1:1 on rabbitmq, the service keeps the messages that haven't been listened to or acknowledged by the listener so that when a listener is up, it receives the backlog and it is cleared. How can or what configuration is required to make this also work for publish/subscribe which is 1:many (fanout-like)?

I am using amqplib for nodejs

Solution

    1. Rabbitmq queue should be durable

    2. This makes sure the queue is declared before attempting to consume from it

    durable: true
});

**sample code**

var amqp = require('amqplib/callback_api');

amqp.connect('amqp://localhost', function(error0, connection) {
  if (error0) {
    throw error0;
  }
 connection.createChannel(function(error1, channel) {
    if (error1) {
      throw error1;
    }
   var queue = 'task_queue';

   var msg = process.argv.slice(2).join(' ') || "Hello World!";

    channel.assertQueue(queue, {
      durable: true
    });
    channel.sendToQueue(queue, Buffer.from(msg), {
      persistent: true
    });
   console.log(" [x] Sent '%s'", msg);
  });
  setTimeout(function() {
    connection.close();
    process.exit(0)
  }, 500);
});


----------