SOA - data access for business services as a separate web service or no?

Question

Currently inside my organization we are trying to come up w/ some conventions for a pilot SOA project. At first glance we thought it would be best to force users of the service to use the business service w/out direct access to any data endpoints .. but are there specific scenarios where this is not true or it might be "valid" for developers to have access to specific data endpoints outside of a service?

I always fear that if we open this up, it will actually hurt reuse because everyone will just "re-invent" similar business services using the same back-end data as it's available and would be "in theory .. easier" to just write a new business service rather than ask "what does this other service do that uses my database?"

Because even if the service is almost a direct pass through to the database we would have the ability to apply rules that would save developers time and ultimately the business money.

Thoughts?

Answer 1

Wouldn't your webservice just be a thin wrapper for your business layer anyway? Your service layer probably shouldn't have anything more than your business layer besides some dumbed-down DTOs perhaps. Then noone is asking "what does this other service do that uses my database?" because it isn't using your db, it is using your BL.

Answer 2

You're waving a red flag when you describe "forcing" users to do anything. Maybe you can think about your question and rephrase it in terms something like "enable" users, because this should be the starting point for your decision, and SOA offers advantages and disadvantages for different UI strategies.