c# - 向 TestServer 的 HttpClient 添加一个委托(delegate)处理程序(传出请求中间件)

Question

是否可以添加自定义 DelegationHandler (传出请求中间件)到 HttpClient由 asp.net 核心 TestServer 构建?

我正在尝试合并 customization possibilities使用 HttpClientFactory影响HttpClients使用内存测试实用程序 TestServer :

public class ExternalProxySslDowngradeSimulator : DelegatingHandler
{
    protected override Task<HttpResponseMessage> SendAsync(
            HttpRequestMessage request,
            CancellationToken token)
     {
        if (request.RequestUri.Scheme == "https")
                request.RequestUri = new Uri(
                     request.RequestUri.OriginalString.Replace("https:", "http:"));

         return base.SendAsync(request, token);
     }
}

[TestFixture
public class TestClass
{
   [Test]
   public async Task CallApi()
   {
      var builder = new WebHostBuilder()
           .ConfigureAppConfiguration((ctx, config) => { })
           .UseUrl("http://customDomain.com")
           .UseStartup<CustomApi.Startup>();

      var testServer = new Microsoft.AspNetCore.TestHost.TestServer(builder);

      var httpClient = testServer.CreateClient();

      var apiResult = await httpClient.GetAsync("https://customDomain");
   }
}

我找不到插入我的 DelegatingHandler 的方法进入HttpClient从 testServer.CreateClient() 返回

到目前为止我已经尝试过:

Registering a custom HttpClientBuilder (无效):

// did not work:
var builder = new WebHostBuilder()
   .UseStartup<CustomApi.Startup>()
   .ConfigureServices(services =>
   {
        services
          .AddHttpClient("")
          .AddHttpMessageHandler<ExternalProxySslDowngradeSimulator>();

浏览 code for TestServer 它没有与该管道 Hook 。

定制 HttpClientFactoryOptions (没用)

以为我可以绑定(bind)自定义 HttpClientFactoryOptions并将自定义操作添加到 HttpClientFactoryOptions.HttpMessageHandlerBuilderActions .但是 TestServer 并没有像默认的 Http Client Factory 那样真正使用它。

自定义设置TestServer (没用)

浏览文档/源代码没有看到任何地方可以 Hook 。有一个 extension method to further control DI ，但我不明白这怎么能让我进入自定义 HttpMessangeHandler TestServer 正在使用。

Answer 1

因此，您要做的是使用测试服务器(代码示例中的服务器)的 CreateHandler 方法和 HttpClientFactory.Create 方法创建自己的客户端。

var client = HttpClientFactory.Create(Server.CreateHandler(), new CustomDelegate() );
client.BaseAddress = Server.BaseAddress;

这让我花了很长时间才弄清楚。希望这对您有所帮助。

所以你的例子是

var httpClient = HttpClientFactory.Create(testServer.CreateHander(), new ExternalProxySslDowngradeSimulator());
httpClient.BaseAddress = testServer.BaseAddress;