RabbitMQ Service Bus Explained

rabbitmqctl stop_app

This command stops the RabbitMQ application on a particular machine.

RabbitMQ start command

rabbitmqctl start_app

This command starts a RabbitMQ application on a particular machine.

Resetting the RabbitMQ command

rabbitmqctl reset

This command resets the entire RabbitMQ application running on a particular machine. We have to stop the application first every time we try to reset it.

Command to add a new user

rabbitmqctl add_user abc 12345

We can create a new user using this command by mentioning its username and password.

Command to assign a particular role to a newly created user

We can also set a tag for any newly created user using the below command.

rabbitmqctl set_user_tags abc administrator

Command to grant permission to a newly created user

We can also set all kinds of permissions to a newly created user such as read/write permission and configure permission using the below command.

rabbitmqctl set_permissions -p/abc “.*” “.*” “.*”

Permissions can also be changed on the RabbitMQ user interface. We can also create add, update, and delete users from RabbitMQ UI.

Below a simple application has been created that will publish a message to the queue and then there is a subscriber or a message receiver who will pick up the message from the queue.

Publisher. cs

using RabbitMQ.Client;
using System;
using System.Text;

namespace RabbitMQApplication
{
    public class Publisher
    {
        public static void Main(string[] args)
        {
            var factory = new ConnectionFactory() { HostName = "localhost" };
            using (var connection = factory.CreateConnection())
            using (var channel = connection.CreateModel())
            {
                channel.QueueDeclare("Test", false, false, false, null);
                string message = "creating a message using asp.net core rabbitmq";
                var body = Encoding.UTF8.GetBytes(message);
                channel.BasicPublish("", "Test", null, body);
                Console.WriteLine("sent message:{0}", message);
            }

            Console.ReadLine();
        }
    }
}

Output

Subscriber. cs

using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using System;
using System.Text;

namespace RabbitMQconsumer
{
    public class Subscriber
    {
        public static void Main(string[] args)
        {
            var factory = new ConnectionFactory() { HostName = "localhost" };
            using (var connection = factory.CreateConnection())
            using (var channel = connection.CreateModel())
            {
                channel.QueueDeclare("Test", false, false, false, null);
                var consumer = new EventingBasicConsumer(channel);
                consumer.Received += (model, ea) =>
                {
                    var messagebody = ea.Body;
                    var message = Encoding.UTF8.GetString(messagebody);
                    Console.WriteLine("Recieved message:{0}", message);
                };

                channel.BasicConsume("Test", true, consumer);

                Console.ReadLine();
            }
             
        }
    }
}

Output

As we can see from the above images when Publisher. cs published messages to the RabbitMQ service bus, there were 4 messages inside the queue. when Subscriber. cs consumed these messages, connections, and channels were created.

Summary

In this article, we have discussed the architecture of the RabbitMQ service bus. We have discussed each and every component belonging to the RabbitMQ service bus API. We have also created a simple application that will publish a message to the queue and then there is a subscriber or a message receiver who will pick up the message from the queue.