WebAPI服务设计

Question

I'm pretty comfortable with how Asp.NET MVC controllers worked when designing services. However the new WebAPI controllers. how am I supposed to design my services here?

Lets say we have 3 different ways to list eg Users.

Get 10 latest , Get all, Get inactive or whatever.

none of these might need parameters. so how would you solve this in WebAPI

IEnumerable<User> Get10Latest()
IEnumerable<User> GetAll()
IEnumerable<User> GetInactive()

That won't work since they have the same param signature. So what is the correct way to design this here?

Answer 1

You can support multiple methods in one controller for a single HTTP method by using the action parameter.
Eg

public class UsersController : ApiController
{

    [ActionName("All")]
    public HttpResponseMessage GetAll()
    {
        return new HttpResponseMessage();
    }

    [ActionName("MostIQ")]
    public HttpResponseMessage GetMostIQ()
    {
        return new HttpResponseMessage();
    }

    [ActionName("TenLatest")]
    public HttpResponseMessage GetTenLatest()
    {
        return new HttpResponseMessage();
    }

}

Unfortunately, I have not found a way to get a single controller to handle both with and without the action at the same time.

eg

public class UsersController : ApiController
{

    [ActionName("")]  // Removing this attribute doesn't help
    public HttpResponseMessage Get()
    {
        return new HttpResponseMessage();
    }

    [ActionName("All")]
    public HttpResponseMessage GetAll()
    {
        return new HttpResponseMessage();
    }

    [ActionName("MostIQ")]
    public HttpResponseMessage GetMostIQ()
    {
        return new HttpResponseMessage();
    }

    [ActionName("TenLatest")]
    public HttpResponseMessage GetTenLatest()
    {
        return new HttpResponseMessage();
    }

}

Being able to use a single controller for a collection resource and all of its subsets would be nice.

Answer 2

Someone will probably be along and wrap me on the knuckles for this, but you need to configure your routing to handle the Gets. This is how I got it working with the above operations:

config.Routes.MapHttpRoute(
            name: "CustomApi",
            routeTemplate: "api/{controller}/{action}",
            defaults: new { id = RouteParameter.Optional }
        );

So now your requests are mapped to the correct controller -> action via the route template. Note that the new route needs to be registered first in WebApiConfig.cs. If you keep the old, default one.

EDIT

Having re-read the question I realize I wasn't quite answering the design question. I would think that one way to go about it, from a REST perspective, would be to use a separate resource to expose the proper collections (Get10Latest for example) since I assume that there is a business reason for exposing that exact subset of data through the service. In that case you'd expose that resource though a single Get in its own Controller (if that is the desired behaviour).

Answer 3

Well why not have urls like this:

GET /users
GET /users/latest
GET /users/inactive

Using routing you could route them to

public classs UserController : ApiController
{
    public IEnumerable<User> Get(string mode)
    {
        // mode is in routing restricted to be either empty, latest, or inactive
     }
 }

Otherwise use multiple controllers. The use of action names in Web API is kind of a wrong way to about it.