如何在 dotnet 核心中为 HttpClient 指定 HTTP/2 "prior knowledge" 模式？

Question

使用 dotnet Core 3.1，以下服务器接受 HTTP/2 个请求：

using System;
using System.Threading.Tasks;
using System.Net.Http;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore;
using System.Threading;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Server.Kestrel.Core;

namespace http2
{
    class Program
    {
        static void Main(string[] args)
        {
            CreateWebHostBuilder(args).Build().Run();
        }

        public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>()
                .ConfigureKestrel((context, serverOptions) =>
                {
                    serverOptions.ListenLocalhost(8080, listenOptions =>
                    {
                        listenOptions.Protocols = HttpProtocols.Http2; // this line is important
                    });
                });
    }

    class Startup
    {
        public void Configure(IApplicationBuilder app)
        {
            app.Run(context => ProcessAsync(context));
        }

        internal async Task<bool> ProcessAsync(HttpContext context)
        {
            await context.Response.WriteAsync("This is the response: toto");
            return true;
        }
    }
}

例如，如果您尝试以下操作，您会得到响应： curl --silent --http2-prior-knowledge http://localhost:8080

我的问题是如何实际执行 curl 正在做的事情？但是在 C# 中。

我试过：

static void ClientCode(object parameter)
{
      SocketsHttpHandler handler = new SocketsHttpHandler();
      using (var client = new HttpClient(handler))
      {
           var request = new HttpRequestMessage(HttpMethod.Get, "http://localhost:8080");
           request.Version = new Version(2, 0);

           var response = client.SendAsync(request).Result;
           if (response.IsSuccessStatusCode)
           {
                var s = response.Content.ReadAsStringAsync().Result;
                Console.WriteLine(s);
           }
      }
}

但我只是遇到了一个例外。

是否可以在 C# 和 dotnet Core 中将 prior knowledge mode 与 HttpClient 一起使用？

Answer 1

My question is about how to actually do what curl is doing ? But in C#.

请尝试将 System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport 开关设置为 true，如下所示。

AppContext.SetSwitch("System.Net.Http.SocketsHttpHandler.Http2UnencryptedSupport", true);

SocketsHttpHandler handler = new SocketsHttpHandler();
using (var client = new HttpClient(handler))
{
    var request = new HttpRequestMessage(HttpMethod.Get, "http://localhost:8080");
    request.Version = new Version(2, 0);

    var response = client.SendAsync(request).Result;

    if (response.IsSuccessStatusCode)
    {
        var s = response.Content.ReadAsStringAsync().Result;
        Console.WriteLine(s);
    }
}

测试结果

Answer 2

我在 net5.0 上，只有在显式设置 VersionPolicy 时才能使其工作

var request = new HttpRequestMessage(HttpMethod.Get, "http://localhost:5001/test");
request.Version = new Version(2, 0);
request.VersionPolicy = HttpVersionPolicy.RequestVersionExact;

如何在 dotnet 核心中为 HttpClient 指定 HTTP/2 "prior knowledge" 模式？

How to specify HTTP/2 "prior knowledge" mode for HttpClient in dotnet core?

c#

dotnet-httpclient

http2

asp.net-core