为什么'DefaultInlineConstraintResolver'无法解析'apiVersion'

Question

我有一个基本的WebApi实现设置与默认值控制器.

在阅读关于RESTful WebApi Versioning的博客后,我决定将该软件包集成到一个新的WebApi项目中.

我已经添加了NuGet包Microsoft.AspNet.WebApi.Versioning来协助我的API版本控制.以下是我所遵循的包配置说明的URL:

https://github.com/Microsoft/aspnet-api-versioning/wiki/Configuring-Your-Application

我的价值观控制器非常简单.我已经将装饰添加到了我的Get方法中.这是代码:

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

// POST api/values
public void Post([FromBody]string value)
{
}

// PUT api/values/5
public void Put(int id, [FromBody]string value)
{
}

// DELETE api/values/5
public void Delete(int id)
{
}
}

不幸的是,只要我将以下代码行添加到控制器中,整个过程就会爆炸:

[Route("api/v{version:apiVersion}/values")]

这是一个正在返回的错误消息:

The inline constraint resolver of type 'DefaultInlineConstraintResolver' was unable to resolve the following inline constraint: 'apiVersion'. 

Line 82:             GlobalConfiguration.Configure(WebApiConfig.Register);

这是我在Startup.cs中的代码

public void Configuration(IAppBuilder app)
        {
            // HTTP Configuration
            HttpConfiguration config = new HttpConfiguration();
            //config.MapHttpAttributeRoutes();

            // Configure API Versioning
            config.AddApiVersioning();
            var constraintResolver = new DefaultInlineConstraintResolver()
            {
                ConstraintMap =
                {
                    ["apiVersion"] = typeof( ApiVersionRouteConstraint ) // or mvc routing?
                }
            };
            config.MapHttpAttributeRoutes(constraintResolver);   

            // Configure the API to accept token authentication
            ConfigureOAuthTokenConsumption(app);

            // CORS
            app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);

            // Configure the Authorization server
            ConfigureOAuth(app);

            // Use WebAPI
            app.UseWebApi(config);



             // Moved from global.asax
            AreaRegistration.RegisterAllAreas();
            GlobalConfiguration.Configure(WebApiConfig.Register);
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
        }

我认为调用AddApiVersioning并提供文档中概述的constraintResolver可以解决问题,但事实并非如此.现在我正在努力做下一步该做什么.

config.AddApiVersioning();
            var constraintResolver = new DefaultInlineConstraintResolver()
            {
                ConstraintMap =
                {
                    ["apiVersion"] = typeof( ApiVersionRouteConstraint ) // or mvc routing?
                }
            };
            config.MapHttpAttributeRoutes(constraintResolver);

有什么建议？

Answer 1

您应该解析WebApiConfig.cs文件中的版本

     var constraintResolver = new DefaultInlineConstraintResolver()
        {
            ConstraintMap =
            {
                ["apiVersion"] = typeof( ApiVersionRouteConstraint ) 
            }
        };
        config.MapHttpAttributeRoutes(constraintResolver); 

在映射路线之前.我的意思是在config.Routes.MapHttpRoute()之前