带有继承的 Web API 版本控制

Question

我正在尝试让 Web API 版本控制与继承的类一起使用。我正在使用 stock Values 控制器的两个非常简单的变体。

[ApiVersion("1.0")]
[RoutePrefix("api/v{version:apiVersion}/Values")]
[ControllerName("Values")]
public class ValuesController : ApiController
{
    // GET api/values
    [Route("")]
    public IEnumerable<string> Get()
    {
        return new string[] { "value1", "value2" };
    }

    // GET api/values/5
    [Route("{id:int}")]
    public virtual string Get(int id)
    {
        return "value from 1";
    }
}

[ApiVersion("2.0")]
[RoutePrefix("api/v{version:apiVersion}/Values")]
[ControllerName("Values")]
public class Values2Controller : ValuesController
{
    //Want to use the method in the base class
    //public IEnumerable<string> Get()
    //{
    //    return new string[] { "value2-1", "value2-2" };
    // }

    [Route("{id:int}")]
    // GET api/values/5
    public new string Get(int id)
    {
        return "value from 2";
    }
} 

我的启动配置也很简单。

public static void Register(HttpConfiguration config)
{
    var constraintResolver = new DefaultInlineConstraintResolver()
    {
        ConstraintMap = {["apiVersion"] = typeof(ApiVersionRouteConstraint)}
    };
    config.MapHttpAttributeRoutes(constraintResolver);
    config.AddApiVersioning(o => { o.AssumeDefaultVersionWhenUnspecified = true; });
}

未覆盖的路线完全按照我的预期工作 http://localhost:32623/api/v1.0/Values/12 -> “从 1 开始的值” http://localhost:32623/api/v2.0/Values/12 -> “来自 2 的值”

调用v1的默认Get路由 http://localhost:32623/api/v1.0/Values -> 值1，值2

但是在子控制器上尝试相同的路由会导致错误。

http://localhost:32623/api/v2.0/Values

<Message>
The HTTP resource that matches the request URI 'http://localhost:32623/api/v2.0/Values' does not support the API version '2.0'.
</Message>
<InnerError>
<Message>
No route providing a controller name with API version '2.0' was found to match request URI 'http://localhost:32623/api/v2.0/Values'.
</Message>
</InnerError>

错误消息表明被覆盖的成员需要“1.0”路由，我可以在子类中使用类似的方法解决此问题。

[Route("")]
public override IEnumerable<string> Get()
{
    return base.Get();
}

但这在更大的应用程序中似乎不太理想。有没有办法让这项工作按照我想要的方式进行，而不需要这些“空”覆盖？

Answer 1

您需要做的是覆盖DefaultDirectRoutePrivider 以允许路由继承：

public class WebApiCustomDirectRouteProvider : DefaultDirectRouteProvider {
    protected override IReadOnlyList<IDirectRouteFactory>
        GetActionRouteFactories(HttpActionDescriptor actionDescriptor) {
        // inherit route attributes decorated on base class controller's actions
        return actionDescriptor.GetCustomAttributes<IDirectRouteFactory>(inherit: true);
    }
}

完成后，您需要在 Web api 配置中配置它以及自定义路由约束

public static void Register(HttpConfiguration config) {
    var constraintResolver = new DefaultInlineConstraintResolver() {
        ConstraintMap = {["apiVersion"] = typeof(ApiVersionRouteConstraint)}
    };
    var directRouteProvider = new WebApiCustomDirectRouteProvider();
    // Attribute routing. (with inheritance)
    config.MapHttpAttributeRoutes(constraintResolver, directRouteProvider);
    config.AddApiVersioning(_ => { _.AssumeDefaultVersionWhenUnspecified = true; });
}

所以现在继承值控制器现在将拥有派生控制器中可用的基本路由

出于演示目的

[ApiVersion("1.0")]
[RoutePrefix("api/v{version:apiVersion}/Values")]
[ControllerName("Values")]
public class ValuesController : ApiController {

    [HttpGet]
    [Route("")] // GET api/v1.0/values
    public virtual IHttpActionResult Get() {
        return Ok(new string[] { "value1", "value2" });
    }

    [HttpGet]
    [Route("{id:int}")] // GET api/v1.0/values/5
    public virtual IHttpActionResult Get(int id) {
        return Ok("value from 1");
    }
}

[ApiVersion("2.0")]
[RoutePrefix("api/v{version:apiVersion}/Values")]
[ControllerName("Values")]
public class Values2Controller : ValuesController {

    //Will have inherited GET "api/v2.0/Values" route

    // GET api/v2.0/values/5 (Route also inherited from base controller)
    public override IHttpActionResult Get(int id) {
        return Ok("value from 2");
    }
} 

您会注意到子节点中的路由并未用于被覆盖的操作，因为它也将从基本控制器继承。