Return 401 from WCF service

Question

How can I return a HTTP 401 from a WCF service?

Answer 1

Depending on when you need to do the authorization check, you could do it in an HttpModule using something like the following:

HttpContext context = HttpContext.Current;
context.Response.StatusCode = 401;
context.Response.End();

Answer 2

If you are programming a REST-service it can be done this way:

private IWebOperationContext context = new WebOperationContextWrapper(WebOperationContext.Current); // Get the context

context.OutgoingResponse.StatusCode = HttpStatusCode.Unauthorized; // Set the 401

Answer 3

If you're using the WebServiceHost2 factory from the WCF REST Starter Kit, you can also throw specific WebProtocolException and specify a HTTP return code:

There's also a HttpStatusCode.Unauthorized which corresponds to the 401 status code.

See Rob Bagby's excellent blog post Effective Error Handling with WCF REST for more detail on the various ways of specifying HTTP return codes. (screenshots are from Rob's blog post - he deserves all the credit for this.)