How do you inherit route prefixes at the controller class level in WebApi?

Question

Note, I've read about the new routing features as part of WebApi 2.2 to allow for inheritance of routes. This does not seem to solve my particular issue, however. It seems to solve the issue of inheriting action level route attributes, but not route prefixes defined at the class level. http://www.asp.net/web-api/overview/releases/whats-new-in-aspnet-web-api-22#ARI

I would like to do something like this:

[RoutePrefix("account")]
public abstract class AccountControllerBase : ControllerBase { }

[RoutePrefix("facebook")]
public class FacebookController : AccountControllerBase
{
    [Route("foo")]
    public async Task<string> GetAsync() { ... }
}

[RoutePrefix("google")]
public class GoogleController : AccountControllerBase
{
    [Route("bar")]
    public async Task<string> GetAsync() { ... }
}

I would like the account route prefix to be inherited, so when defining the Facebook and Google controllers, I get routes:

~/account/facebook/foo
~/account/google/bar

Currently, routes are getting defined without the account portion from the base class.

Answer 1

I had a similar requirement. What i did was:

public class CustomDirectRouteProvider : DefaultDirectRouteProvider
{
    protected override string GetRoutePrefix(HttpControllerDescriptor controllerDescriptor)
    {
        var routePrefix =  base.GetRoutePrefix(controllerDescriptor);
        var controllerBaseType = controllerDescriptor.ControllerType.BaseType;

        if (controllerBaseType == typeof(BaseController))
        {
            //TODO: Check for extra slashes
            routePrefix = "api/{tenantid}/" + routePrefix;
        }

        return routePrefix;
    }
}

Where BaseController is the one defining what is the prefix. Now normal prefixes work and you can add your own. When configuring routes, call

config.MapHttpAttributeRoutes(new CustomDirectRouteProvider());