Ensuring Reliability with WF services

Question

I am new to WF services & just exploring it.

I need to trigger a workflow whenever an item is added to a table.

I am seeing a lot of hype about WCF WF service & lets say i go with that option. This will be the flow

Insert item -> Call the WCF WF service

Calling a service is not always reliable. What if the connection is broken Or someone entered a wrong url in the client config.

In general what is the best practice when using WCF WF. How can i be assured that the Workflow is indeed triggered.

Answer 1

Re: Someone entered a wrong url in the client config. This is a general deployment/ops thing. No matter what you choose. If it is configured wrong its not going to work.

Re: What if the connection is broken. This is also something that can occur but more something the architecture might need to cater for. In general using some kind if persisted message to start the workflow will do the trick. The easy and inbuilt WCF solution is to use, transaction, MSMQ as a transport. That way of the service is unreachable the message will be queued and transmitted later. Another option is to store the events in a database table and send them. If you can send the message successfully then delete the message from the table. Basically you are doing manually what MSMQ is doing automatically for you but there some benefits like being able to do request/response and not being depended on a part of Windows that is not installed by default,