Aspnet Core 3 端点路由配置源代码

学习：《asp.net core 3.x Endpoint终结点路由1-基本介绍和使用》、《ASP.NET Core 2.2 : 十六.扒一扒新的Endpoint路由方案》

《.netcore入门16：aspnetcore之终结点路由工作原理》、《.netcore入门13：aspnetcore源码之如何在程序启动时将Controller里的Action自动扫描封装成Endpoint》。

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1、Aspnet Core 3 端点路由配置，在 Startup 类的 Configure 方法中：

   app.UseRouting();     //必须放在后者之前，而且 必须是 注册在 相同的 App（IApplicationBuilder），代码注释中有特别说明 ！

   app.UseEndpoints( Action<IEndpointRouteBuilder> configure);

从代码中看出一点：UseRouting() ，会在属性中new一个IEndpointRouteBuilder： 

            app.Properties[EndpointRouteBuilder] = new DefaultEndpointRouteBuilder(builder);

            UseEndpoints( Action<IEndpointRouteBuilder> configure)  执行时，会将前面New的 DefaultEndpointRouteBuilder 实例取出，并进一步配置它： configure(EndpointRouteBuilder实例) 。

2、接口 IEndpointRouteBuilder （V3.0才有，另外，还有一个 IRouteBuilder），

     有一个属性： DataSources （ICollection<EndpointDataSource>） ，定义源代码：https://docs.microsoft.com/zh-cn/dotnet/api/microsoft.aspnetcore.routing.iendpointroutebuilder?view=aspnetcore-3.1  ；    EndpointDataSource  只有一个属性  Endpoints  ( IReadOnlyList<Endpoint> )   

      重点是它的扩展方法。如：

      MapControllers(IEndpointRouteBuilder)，

      MapControllerRoute(IEndpointRouteBuilder, String, String, Object, Object, Object)  即 name, pattern, defaults, constraints, 与 dataTokens.

 

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aspnetcore/src/Http/Routing/src/Builder/EndpointRoutingApplicationBuilderExtensions.cs   源代码地址：

代码 ：https://github.com/dotnet/aspnetcore/blob/1c126ab773059d6a5899fc29547cb86ed49c46bf/src/Http/Routing/src/Builder/EndpointRoutingApplicationBuilderExtensions.cs

 说明：校验代码中用到一个  RoutingMarkerService   标识类，一个没有属性的空类，https://github.com/dotnet/aspnetcore/blob/763720b092b124b4cb179296e450ff23b2ce097a/src/Http/Routing/src/RoutingMarkerService.cs

private const string EndpointRouteBuilder = "__EndpointRouteBuilder";

public static IApplicationBuilder UseRouting(this IApplicationBuilder builder)

{
       if (builder == null)   {    throw new ArgumentNullException(nameof(builder));   }

       VerifyRoutingServicesAreRegistered(builder);

       var endpointRouteBuilder = new DefaultEndpointRouteBuilder(builder);
        builder.Properties[EndpointRouteBuilder] = endpointRouteBuilder;

        return  builder.UseMiddleware<EndpointRoutingMiddleware>(endpointRouteBuilder);
}

public static IApplicationBuilder UseEndpoints(this IApplicationBuilder builder, Action<IEndpointRouteBuilder> configure)
{
       if (builder == null)  {   throw new ArgumentNullException(nameof(builder));  }

       if (configure == null) { throw new ArgumentNullException(nameof(configure)); }

       VerifyRoutingServicesAreRegistered(builder);      //此方法中用到  RoutingMarkerService   标识类

       VerifyEndpointRoutingMiddlewareIsRegistered(builder, out var endpointRouteBuilder);

       configure(endpointRouteBuilder);

        // Yes, this mutates an IOptions. We're registering data sources in a global collection which
        // can be used for discovery of endpoints or URL generation.
        // Each middleware gets its own collection of data sources, and all of those data sources also
       // get added to a global collection.
        var routeOptions = builder.ApplicationServices.GetRequiredService<IOptions<RouteOptions>>();
        foreach (var dataSource in endpointRouteBuilder.DataSources)
        {
             routeOptions.Value.EndpointDataSources.Add(dataSource);
        }

        return builder.UseMiddleware<EndpointMiddleware>();
}

 

Microsoft.AspNetCore.Routing    DefaultEndpointRouteBuilder 定义（内部类）

https://github.com/dotnet/aspnetcore/blob/658b37d2bd3b0da2c07e25b53fa5c97ce8d656d3/src/Http/Routing/src/DefaultEndpointRouteBuilder.cs

internal class DefaultEndpointRouteBuilder : IEndpointRouteBuilder
{
      public DefaultEndpointRouteBuilder(IApplicationBuilder applicationBuilder)
      {
          ApplicationBuilder = applicationBuilder ?? throw new ArgumentNullException(nameof(applicationBuilder));
          DataSources = new List<EndpointDataSource>();
      }

      public IApplicationBuilder ApplicationBuilder { get; }

     public IApplicationBuilder CreateApplicationBuilder() => ApplicationBuilder.New();

     public ICollection<EndpointDataSource> DataSources { get; }

     public IServiceProvider ServiceProvider => ApplicationBuilder.ApplicationServices;
}

EndpointDataSource    https://docs.microsoft.com/zh-cn/dotnet/api/microsoft.aspnetcore.routing.endpointdatasource?view=aspnetcore-3.1

继承：Microsoft.AspNetCore.Routing.CompositeEndpointDataSource、 Microsoft.AspNetCore.Routing.DefaultEndpointDataSource

定义：https://github.com/dotnet/aspnetcore/blob/85e2147ff037cc9950249fbb9d095ad47ec4184a/src/Http/Routing/src/DefaultEndpointDataSource.cs

有一属性 ：IReadOnlyList<Endpoint>       Endpoint   被继承：Microsoft.AspNetCore.Routing.RouteEndpoint     

RouteEndpoint：的几个属性 ： DisplayName（String）、Metadata（EndpointMetadataCollection 集合）、RequestDelegate、【Order（int，代表站点优先级，值小优先）、RoutePattern （路由模式）】。

 

 

 

Endpoints