Message Queuing - RabbitMQ

RabbitMQ

• Accepts and forwards messages.
• Components are
• Producer (Forwards the messages)
• Consumer (Receiver)
• Queue (an infinite buffer of messages)
• Confirms to AMQP (Advanced Message Queuing Protocol)

Steps of the Producer (Pyhthon code)

1. Establish the connenction

import pika connection = pika.BlockingConnection(pika.ConnectionParameters( 'localhost')) channel = connection.channel()

2. Create a Queue

channel.queue_declare(queue='hello')

3. Send the message to the queue (Using an exchange method)

channel.basic_publish(exchange='',
                      routing_key='hello',
                      body='Hello World!')
print(" [x] Sent 'Hello World!'")

4. Close the connection

connection.close()


Steps of the Consumer 


1. Declare the Queue



channel.queue_declare(queue='hello')



2. Define the callback methodw which prints the message to be received


def callback(ch, method, properties, body):
    print(" [x] Received %r" % body)




3. Define the Producer queue from which the messages should be received

channel.basic_consume(callback,
                      queue='hello',
                      no_ack=True)


4. Never ending loop which consumes messages continuously
print(' [*] Waiting for messages. To exit press CTRL+C')
channel.start_consuming()