如何在.NET中拦截服务器端HTTP请求：JustEat.HttpClientInterception源码解析

【实例简介】
JustEat.HttpClientInterception是一个针对.NET Standard 2.0及更高版本和.NET Framework 4.7.2的库，用于拦截服务器端的HTTP依赖。它基于DelegatingHandler的实现，可以直接作为HttpMessageHandler的实现使用，或者提供给HttpClient的实例。这使得在不需要托管HTTP服务器的情况下使用它变得轻量级。

安装：通过.NET SDK从NuGet安装JustEat.HttpClientInterception。

// 示例：拦截HTTP GET请求并返回自定义响应
var options = new HttpClientInterceptorOptions();
var builder = new HttpRequestInterceptionBuilder();

builder
    .Requests()
    .ForGet()
    .ForHttps()
    .ForHost("public.je-apis.com")
    .ForPath("terms")
    .Responds()
    .WithJsonContent(new { Id = 1, Link = "https://www.just-eat.co.uk/privacy-policy" })
    .RegisterWith(options);

using var client = options.CreateHttpClient();

// 执行
string json = await client.GetStringAsync("https://public.je-apis.com/terms");

此外，还可以通过"HTTP bundle"文件配置要拦截的HTTP请求及其相应的响应。这为在.NET应用程序中进行测试提供了强大的灵活性和控制能力。
【实例截图】
【核心代码】
文件清单
└── httpclient-interception-57f983d7bf51154d3deda83cc85cf782d7be58e2
    ├── build.ps1
    ├── CODE_OF_CONDUCT.md
    ├── Directory.Build.props
    ├── Directory.Build.targets
    ├── Directory.Packages.props
    ├── global.json
    ├── HttpClientInterception.ruleset
    ├── HttpClientInterception.sln
    ├── justeat-oss.snk
    ├── LICENSE
    ├── mdsnippets.json
    ├── NuGet.config
    ├── package-icon.png
    ├── README.md
    ├── samples
    │   ├── README.md
    │   ├── SampleApp
    │   │   ├── appsettings.Development.json
    │   │   ├── appsettings.json
    │   │   ├── Extensions
    │   │   │   └── HttpClientExtensions.cs
    │   │   ├── Handlers
    │   │   │   ├── AddRequestIdHandler.cs
    │   │   │   └── TimingHandler.cs
    │   │   ├── Program.cs
    │   │   ├── Properties
    │   │   │   └── launchSettings.json
    │   │   ├── SampleApp.csproj
    │   │   ├── Services
    │   │   │   ├── IGitHub.cs
    │   │   │   └── Repository.cs
    │   │   └── wwwroot
    │   │       └── favicon.ico
    │   └── SampleApp.Tests
    │       ├── HttpClientInterceptionFilter.cs
    │       ├── HttpServerCollection.cs
    │       ├── HttpServerFixture.cs
    │       ├── ReposTests.cs
    │       ├── SampleApp.Tests.csproj
    │       ├── testsettings.json
    │       └── xunit.runner.json
    ├── SECURITY.md
    ├── src
    │   └── HttpClientInterception
    │       ├── BundleExtensions.cs
    │       ├── Bundles
    │       │   ├── Bundle.cs
    │       │   ├── BundleFactory.cs
    │       │   ├── BundleItemConverter.cs
    │       │   ├── BundleItem.cs
    │       │   ├── BundleJsonSerializerContext.cs
    │       │   └── http-request-bundle-schema.json
    │       ├── DelegateHelpers.cs
    │       ├── HttpClientInterceptorOptions.cs
    │       ├── HttpClientInterceptorOptionsExtensions.cs
    │       ├── HttpInterceptionResponse.cs
    │       ├── HttpRequestInterceptionBuilder.cs
    │       ├── HttpRequestInterceptionBuilderExtensions.cs
    │       ├── HttpRequestNotInterceptedException.cs
    │       ├── InterceptingHttpMessageHandler.cs
    │       ├── JustEat.HttpClientInterception.csproj
    │       ├── Matching
    │       │   ├── DelegatingMatcher.cs
    │       │   ├── RegistrationMatcher.cs
    │       │   └── RequestMatcher.cs
    │       ├── PublicAPI
    │       │   ├── net472
    │       │   │   ├── PublicAPI.Shipped.txt
    │       │   │   └── PublicAPI.Unshipped.txt
    │       │   ├── net6.0
    │       │   │   ├── PublicAPI.Shipped.txt
    │       │   │   └── PublicAPI.Unshipped.txt
    │       │   ├── net7.0
    │       │   │   ├── PublicAPI.Shipped.txt
    │       │   │   └── PublicAPI.Unshipped.txt
    │       │   └── netstandard2.0
    │       │       ├── PublicAPI.Shipped.txt
    │       │       └── PublicAPI.Unshipped.txt
    │       ├── StringSyntaxAttribute.cs
    │       ├── SystemTextJsonExtensions.cs
    │       └── WarningMessages.cs
    ├── stylecop.json
    └── tests
        ├── HttpClientInterception.Benchmarks
        │   ├── CustomBenchmarkConfig.cs
        │   ├── GitHubJsonSerializerContext.cs
        │   ├── GitHubOrganization.cs
        │   ├── IGitHub.cs
        │   ├── InterceptionBenchmarks.cs
        │   ├── JustEat.HttpClientInterception.Benchmarks.csproj
        │   ├── organization.json
        │   └── Program.cs
        └── HttpClientInterception.Tests
            ├── BenchmarkTests.cs
            ├── Bundles
            │   ├── BundleExtensionsTests.cs
            │   ├── content-as-html-base64.json
            │   ├── content-as-html-string.json
            │   ├── content-as-json-array.json
            │   ├── content-as-json-object.json
            │   ├── content-as-null-json.json
            │   ├── http-methods-versions.json
            │   ├── http-request-bundle.json
            │   ├── http-status-codes.json
            │   ├── ignoring-path.json
            │   ├── ignoring-query.json
            │   ├── invalid-bundle-version.json
            │   ├── invalid-content-format.json
            │   ├── invalid-status-code.json
            │   ├── invalid-uri.json
            │   ├── invalid-version.json
            │   ├── no-content.json
            │   ├── no-uri.json
            │   ├── null-items.json
            │   ├── sample-bundle.json
            │   ├── skipped-item-bundle.json
            │   ├── templated-bundle-base64.json
            │   ├── templated-bundle-json.json
            │   ├── templated-bundle-json-no-parameters.json
            │   ├── templated-bundle-null-headers.json
            │   └── templated-bundle-string.json
            ├── example-bundle.json
            ├── Examples.cs
            ├── GitHub
            │   ├── IGitHub.cs
            │   └── Organization.cs
            ├── HttpAssert.cs
            ├── HttpClientInterceptorOptionsExtensionsTests.cs
            ├── HttpClientInterceptorOptionsTests.cs
            ├── HttpRequestInterceptionBuilderTests.cs
            ├── InterceptingHttpMessageHandlerTests.cs
            ├── JustEat.HttpClientInterception.Tests.csproj
            └── xunit.runner.json

23 directories, 111 files