File Processing with Workflow Foundation

Question

I have been tasked with building a new workflow system to handle our service orders. I have been investigating Windows Workflow Foundation as the engine for managing the workflow steps, and like what I see up until file processing.

We have a step in our workflow where we are waiting for a file to be returned from a vendor. The file contains multiple records each mapping to an individual workflow. The idea was to use the persistence features within WF so that once the data is returned in the file, the rest of the workflow can continue.

The problem with the persistence model is the scalability of calling the WF service for each line in a file using something like SSIS. For small files this isn't an issue, but there is the possibility for the files to get very large.

Has anyone done anything similar to this with Workflow Foundation?

Thanks, Chris

Answer 1

Your best bet would be to create a custom WCF channel based upon reading/writing files from a directory. Then your workflow can use the normal WCF Send/Receive activities and you can easily mock up a test service (with a more standard channel). There's a good blog post series at http://blogs.msdn.com/drnick/archive/2006/04/17/577354.aspx about this, though it's a little outdated. I found I had to implement some additional methods from the abstract class. I also made changes to support one-way channels (the series covers Request/Reply).