How to replace celery task with azure service bus in a django application?

Question

I am asked to use the azure service bus instead of celery in a Django application.

Read the documentation provided but didn't get a clear picture of using service bus instead of a celery task. Any advice provided would be of great help.

Answer 1

Before getting into it, I would like to highlight the differences between Azure Service Bus and Celery.

Azure Service Bus :

Microsoft Azure Service Bus is a fully managed enterprise integration message broker.

You could refer this to know more about the service bus

Celery :

Distributed task queue. Celery is an asynchronous task queue/job queue based on distributed message passing.

I could think of 2 possibilities in your case :

1. You would like to use Service Bus with Celery in place of other message brokers.
2. Replace Celery with the Service Bus

1 : You would like to use Service Bus with Celery in place of other message brokers.

You could refer this to understand why celery needs a message broker. I am not sure which messaging broker you are using currently, but you could use the Kombu library to meet your requirement.

Reference for Azure Service Bus : https://docs.celeryproject.org/projects/kombu/en/stable/reference/kombu.transport.azureservicebus.html

Reference for others : https://docs.celeryproject.org/projects/kombu/en/stable/reference/index.html

2 : Replace Celery with the Service Bus completely To meet your requirement :

Consider

• Message senders are producers
• Message receivers are consumers

These are two different application that you will have to work on.

You could refer the below to get more sample code to build on.

https://github.com/Azure/azure-sdk-for-python/tree/master/sdk/servicebus/azure-servicebus/samples

Explanation :

• Every time you would like to execute the actions, you could send messages to a topic from the producer client.
• The Consumer Client - the application that is listening, will receive the message and process the same. You could attach your custom process to it - in that way the your custom process gets executed whenever a message is received at the consumer client end.

The below is sample of the receiving client :

from azure.servicebus.aio import SubscriptionClient
import asyncio
import nest_asyncio
nest_asyncio.apply()

        
Receiving = True

#Topic 1 receiver : 
conn_str= "<>"
name="Allmessages1"
SubsClient = SubscriptionClient.from_connection_string(conn_str, name)
receiver =  SubsClient.get_receiver()

async def receive_message_from1():
    await receiver.open()
    print("Opening the Receiver for Topic1")
    async with receiver:
      while(Receiving):
        msgs =  await receiver.fetch_next()
        for m in msgs:
            print("Received the message from topic 1.....")
            ##### - Your code to execute when a message is received - ########
            print(str(m))
            ##### - Your code to execute when a message is received - ########
            await m.complete()
            
            
loop = asyncio.get_event_loop()
topic1receiver = loop.create_task(receive_message_from1())

the section between the below line would be instruction that will be executed every time a message is received.

##### - Your code to execute when a message is received - ########