Swagger在OWIN启动Web API C＃中不起作用

问题描述

我已经在Web API的OWIN startup.cs文件中实现了Swagger，但是当我尝试打开Swagger UI页面时，它显示 HTTP错误404.0-未找到
>

检查Swagger UI的URL：https：// localhost：5001 / swagger

这是我的实现方式，请帮助我所缺少的内容。

Startup.cs

public class Startup
{
   public void Configuration(IAppBuilder app)
   {
     app.Map("/api",map => { ConfigureApiArea(map); });
   }

   private void ConfigureApiArea(IAppBuilder map)
   {
            var config = CreateTypedConfiguration<BaseApiController>();

            //Json Settings
            JsonFormatterSettings(config);

            ConfigureAutofac(config,map);
            ConfigureOAuth(map);

            config.EnableCors(new EnableCorsAttribute("*","*","Paging-Headers,X-Error"));
            map.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
            config.EnsureInitialized();


            map.UseWebApi(config);
   }

   private HttpConfiguration CreateTypedConfiguration<TBaseController>() where TBaseController : IHttpController
   {
            var config = new HttpConfiguration();
            config.Services.Replace(typeof(IHttpControllerTypeResolver),new 
            TypedHttpControllerTypeResolver<TBaseController>());
            config.EnableSwagger();
            config.MapHttpAttributeRoutes(new TypedDirectRouteProvider<TBaseController>());
            return config;
   }

}

SwaggerExtensions.cs

 public static class SwaggerExtensions
    {
        public static HttpConfiguration EnableSwagger(this HttpConfiguration httpConfiguration)
        {
            httpConfiguration
                .EnableSwagger(c => c.SingleApiVersion("v1","MyWebAPI"))
                .EnableSwaggerUi();

            return httpConfiguration;
        }
    }

MyController.cs

public class MyController : BaseApiController
{
    [AllowAnonymous]
    [HttpGet]
    [Route("orders/{orderId}")]
    public IHttpActionResult Getorder([FromUri]string orderId) {
        return Ok();
    }
}

BaseApiController.cs

 public class BaseApiController : ApiController { }

解决方法

实际上是@Dai所建议的https://localhost:5001/api/swagger，之所以不起作用，是因为方法MessageHandlers中的自定义ConfigureAutofac(config,map)（OP代码未显示）没有处理路径中带有/swagger的请求。

方法MessageHandler中的

ConfigureAutofac(config,map)代码被省略：

private void ConfigureAutofac(HttpConfiguration config,IAppBuilder app)
{
    var builder = new ContainerBuilder();    
    
    //code omitted for brevity ...

    //Register Web API controllers.
    builder.RegisterApiControllers(Assembly.GetExecutingAssembly())
    .InstancePerRequest();

    //Register the Autofac filter provider.
    builder.RegisterWebApiFilterProvider(config);

    //Register the Autofac model binder provider.
    builder.RegisterWebApiModelBinderProvider();

    //code omitted for brevity ...
    
    var container = builder.Build();

    //Set the dependency resolver to be Autofac.
    config.DependencyResolver = new AutofacWebApiDependencyResolver(container);
    config.MessageHandlers.Insert(0,new ApiDelegatingHandler());
    config.MessageHandlers.Insert(1,new ActivityLogHandler());

    app.UseAutofacMiddleware(container);
    app.UseAutofacWebApi(config);
}

自定义MessageHandler中唯一需要做的更改就是处理此问题，如下所示：

public class ApiDelegatingHandler : DelegatingHandler
{
    protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request,CancellationToken cancellationToken)
    {
        if (request.RequestUri.PathAndQuery.Contains("/swagger")) 
            return await base.SendAsync(request,cancellationToken);

        //code omitted for brevity ...
    }
}