Azure Webjob to run whilst listening to events?

Question

I will have an Azure webjob which will run every x minutes. The job listens to EventHub (pub/sub) for any incoming messages and processes the message.

What is the best way to create/design the webjob so that it stays awake processing the messages? I am unsure if always on is the right way to do this or just run the webjob every few minutes however during the executing of the webjob, I want the code to run so it can wait and listen for messages rather than just exiting almost immediately (imagine program.cs without a console.readline!)

Any ideas or thoughts?

Answer 1

You have 3 main options:

1. Create a console app and use Event Processor Host. Deploy it as a continuous web job.

2. Create a console app and use WebJobs SDK to create an EventHub-triggered function. Deploy it as a continuous web job.

3. Create an Azure Function with Event Hub trigger.

In 1 and 2 you will pay per hour of your Web App Plan instance. There's no point in making job timer-based instead of continuous: you keep paying per hour unless you shut down the Web App instance.

In 3 you pay per function execution time, which might be much cheaper if the amount of events is low.