I have a WCF service that needs to get called so that the call will trigger a 2-3 hour of processing. I'm using windows C# client application to call the service and have set the timeouts to all the max values. When I deployed this to Windows Azure, the WCF process that was triggered by the client seems to stop after a certain moment. The client doesn't get the timeout exceptions. I can use Azure Worker Role, but the process can only be completed using only the WCF code because it is a complicated operation. In other words I can't just schedule Worker Role that executes a simple edit/insert operation to a database. So I kind of have a chicken and egg problem. The background process needs the WCF code to do the background operation, but the WCF seems to stop after a certain while on Azure. What is a way to execute a long running call in WCF and plus how to execute a long running call on Azure that needs to use the hosted cloud service WCF code to do the long running operation?
2 Answers
This is because of the load balancer. The timeout used to be 60 seconds, but a few months ago this was increased to 'more than 60 seconds' (depending on the concurrent connections). Anyways, you need to keep the connection alive in order to avoid the timeout.
I suggest you try implementing this in your WCF client/service: WCF Azure Net.TCP Keep Alive
Why not rethink your architecture? Instead of depending on a connection (that can be disconnected for whatever reason), why not simply have your client drop a message in a queue? Your worker role picks up the message from the queue, does the 2-3 hour processing and once it's done it drops a message in another queue. Finally your client polls that other queue and once a message arrives there it knows the process is complete.
