CRUD Operations on Underlying POCO data via OData/WCF Data Services

Question

I’m trying to write an OData service in C#2010 that exposes some POCO to a jQuery web client via JSON, but also allows updates to the underlying data. I’ve found lots of examples of read-only POCO data via OData and lots of examples of updatable data via Entity Framework and OData.

My problem is that the data is in a proprietary database so there needs to be a business logic layer to handle the DB updates and I don’t see where this fits in the OData/WCF Data Services model. I’m populating the POCO entities using IQueryable lists and exposing them using SetEntitySetAccessRule, but how do I call a method in the business logic/data model layer to persists data to the DB?

Should I be using SetServiceOperationAccessRule to expose service methods? If so, could anyone point me in the direction of a simple example please?

Thanks

Answer 1

My suggestion would be a custom WCF Data services provider, so that you can have a custom implementation of IDataServiceUpdateProvider. There is a good blog series at http://blogs.msdn.com/b/alexj/archive/2010/01/07/data-service-providers-getting-started.aspx

Answer 2

Rich's suggestion to implement IUpdatable/IDataServiceUpdateProvider is correct. That's the way to support Update operations (the EF provider implements this in-box, the reflection provider doesn't so you have to do that yourself). You can implement IUpdatable even when using reflection provider. Just make your context class (the one you pass in as T to DataService) implement the IUpdatable interface.