Spawning and executing a Worker process in Azure

Question

The google has really failed me on this one. I am new to Azure and am only intermediate at .NET

I have an Azure solution going and I've written some code in a Web Role which runs great. What I would like to do now is move some of this code into an Azure Worker, which will be initialized by a controller function in the Web Role

What on earth do I need to do to get this going locally? I have created the Worker project within the SLN. I just need to know how to fire it up and run it.

I think part of my problem is I am assuming these workers behave like Heroku workers... is this the case? Because what I need is something like a queue system (a bunch of "worker tasks" in one big queue).

A lot of the links I've found for tutorials seem to tap dance around how to actually initialize the process from a Web Role.

Answer 1

More info on this, as I've gotten it going now..

If you're coming from a Heroku background, then an Azure Worker is more or less the function in Rails that you'd actually execute with the queue. Unlike Heroku queued operations, an Azure Worker just runs endlessly and keeps polling for new stuff to do... hence the templated sleep(10000) in the Run() function.

The most conventional way I've found to make a Web and Worker talk to each other is by queue messages via Azure ServiceBus which is currently NOT emulated, meaning you need a functioning Azure account to make this work, and it will work even if you are running locally. You just need internet access.

A ServiceBus message can pass an entire object over to the Worker (so long as the Worker proj has the right dependencies in it), so that's kind of nice.

Answer 2

I think you're just having trouble starting the azure emulator along with your worker/web roles? Just set the azure configuration project as the start up project and run that. It'll boot up the emulator along with all your roles.

Answer 3

Workers in Windows Azure are not tasks; they're entire VMs. To make your life easier, memorize this little detail: Web Role instances are Windows Server 2008 with IIS running, and Worker Roles are the same thing but with IIS disabled.

When you added that worker role to your project, you actually now have a new set of virtual machines running (at least one, depending on the instance count you set). These VMs have their own OnStart() and Run() methods you can put code into, for bootstrapping purposes.

If you grab the Windows Azure training kit, you'll see a few labs that show how to communicate between your various role instances (a common pattern being the use of Windows Azure queues). There's a good example of background processes with the Guestbook hands-on lab (the very first lab).