简介

Microsoft.AspNetCore.TestHost是可以用于Asp.net Core 的功能测试工具。很多时候我们一个接口写好了，单元测试什么的也都ok了，需要完整调试一下，检查下单元测试未覆盖到的代码是否有bug。步骤为如下：程序打个断点->F5运行->通常需要登录个测试账号->查找要调试api的入口->获得断点开始调试=>代码报错？很多时候需要停止调试修改->回到第一步。如此反复循环，做着重复的工作，Microsoft.AspNetCore.TestHost正是为了解决这个问题，它可以让你使用xTest或者MSTest进行覆盖整个HTTP请求生命周期的功能测试。

进行一个简单的功能测试

新建一个Asp.net Core WebApi和xUnit项目

ValuesController里面自带一个Action

我们在xUnit项目里面模拟访问这个接口，首选安装如下nuget包：

• Microsoft.AspNetCore.TestHost

• Microsoft.AspNetCore.All（很多依赖懒得找的话直接安装这个集成包，百分之90涉及到AspNetCore的依赖都包含在里面）

然后需要引用被测试的AspnetCoreFunctionalTestDemo项目，新建一个测试类ValuesControllerTest

将GetValuesTest方法替换为如下代码，其中startup类是应用自AspnetCoreFunctionalTestDemo项目

        [Fact]        public void GetValuesTest(){            var client = new TestServer(WebHost.CreateDefaultBuilder().UseStartup<Startup>()).CreateClient();            string result = client.GetStringAsync("api/values").Result;Assert.Equal(result, JsonConvert.SerializeObject(new string[] { "value1", "value2" }));}

此时在ValueController打下断点

运行GetValuesTest调试测试

成功进入断点，我们不用启动浏览器，就可以进行完整的接口功能测试了。

修改内容目录与自动授权

上面演示了如何进行一个简单的功能测试，但是存在两个缺陷：

1. webApi在测试的时候实际的运行目录是在FunctionalTest目录下

2. 对需要授权的接口不能正常测试，会得到未授权的返回结果

1.内容目录

我们可以在Controller的Get方法输出当前的内容目录

内容目录是在测试x项目下这与我们的预期不符，如果webapi项目对根目录下的文件有依赖关系例如appsetting.json则会找不到该文件，解决的办法是在webHost中手动指定运行根目录

[Fact]public void GetValuesTest()
{    var client = new TestServer(WebHost.CreateDefaultBuilder()        .UseContentRoot(GetProjectPath("AspnetCoreFunctionalTestDemo.sln", "", typeof(Startup).Assembly)).UseStartup<Startup>()).CreateClient();    string result = client.GetStringAsync("api/values").Result;Assert.Equal(result, JsonConvert.SerializeObject(new string[] { "value1", "value2" }));
}/// <summary>/// 获取工程路径/// </summary>/// <param name="slnName">解决方案文件名，例test.sln</param>/// <param name="solutionRelativePath">如果项目与解决方案文件不在一个目录，例如src文件夹中，则传src</param>/// <param name="startupAssembly">程序集</param>/// <returns></returns>

private static string GetProjectPath(string slnName, string solutionRelativePath, Assembly startupAssembly)
{      string projectName = startupAssembly.GetName().Name;      string applicationBasePath = PlatformServices.Default.Application.ApplicationBasePath;      var directoryInfo = new DirectoryInfo(applicationBasePath);      do{          var solutionFileInfo = new FileInfo(Path.Combine(directoryInfo.FullName, slnName));          if (solutionFileInfo.Exists){              return Path.GetFullPath(Path.Combine(directoryInfo.FullName, solutionRelativePath, projectName));}directoryInfo = directoryInfo.Parent;}      while (directoryInfo.Parent != null);      throw new Exception($"Solution root could not be located using application root {applicationBasePath}.");}

GetProjectPath方法采用递归的方式找到startup的项目所在路径，此时我们再运行

2.自动授权

每次测试时手动登录这是一件很烦人的事情，所以我们希望可以自动话，这里演示的时cookie方式的自动授权

首先在startup文件配置cookie认证

namespace AspnetCoreFunctionalTestDemo
{        public class Startup{                   public Startup(IConfiguration configuration){Configuration = configuration;}     

        public IConfiguration Configuration { get; }        // This method gets called by the runtime. Use this method to add services to the container.public void ConfigureServices(IServiceCollection services){services.AddMvc();             services.AddAuthentication(o => o.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme).AddCookie(o =>{o.ExpireTimeSpan = new TimeSpan(0, 0, 30);o.Events.OnRedirectToLogin = (context) =>{context.Response.StatusCode = 401;                       return Task.CompletedTask;};});        }        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.public void Configure(IApplicationBuilder app, IHostingEnvironment env){            if (env.IsDevelopment()){app.UseDeveloperExceptionPage();}            app.UseAuthentication();app.UseMvc();}}
}

这里覆盖了cookie认证失败的默认操作改为返回401状态码。

在valuesController新增登录的Action并配置Get的Action需要授权访问

namespace AspnetCoreFunctionalTestDemo.Controllers
{[Route("api/[controller]")]    public class ValuesController : Controller{        

// GET api/values               [HttpGet,Authorize]            public IEnumerable<string> Get([FromServices]IHostingEnvironment env){            

return new string[] { "value1", "value2" };}         // POST api/values[HttpGet("Login")]        public void Login(){             var identity = new ClaimsIdentity(CookieAuthenticationDefaults.AuthenticationScheme);identity.AddClaim(new Claim(ClaimTypes.Name, "huanent"));            var principal = new ClaimsPrincipal(identity);HttpContext.SignInAsync(CookieAuthenticationDefaults.AuthenticationScheme, principal).Wait();}}
}

此时我们使用测试项目测试Get方法

如我们预期，返回了401，说明未授权。我们修改下GetValuesTest

namespace FunctionalTest
{     public class ValuesControllerTest{[Fact]          public void GetValuesTest(){             var client = new TestServer(WebHost.CreateDefaultBuilder().UseStartup<Startup>().UseContentRoot(GetProjectPath("AspnetCoreFunctionalTestDemo.sln", "", typeof(Startup).Assembly))).CreateClient();            var respone = client.GetAsync("api/values/login").Result;SetCookie(client, respone);            var result = client.GetAsync("api/values").Result;}        private static void SetCookie(HttpClient client, HttpResponseMessage respone){            string cookieString = respone.Headers.GetValues("Set-Cookie").First();            string cookieBody = cookieString.Split(';').First();client.DefaultRequestHeaders.Add("Cookie", cookieBody);}        /// <summary>/// 获取工程路径         /// </summary>/// <param name="slnName">解决方案文件名，例test.sln</param>/// <param name="solutionRelativePath">如果项目与解决方案文件不在一个目录，例如src文件夹中，则传src</param>/// <param name="startupAssembly">程序集</param>/// <returns></returns>private static string GetProjectPath(string slnName, string solutionRelativePath, Assembly startupAssembly){             string projectName = startupAssembly.GetName().Name;             string applicationBasePath = PlatformServices.Default.Application.ApplicationBasePath;             var directoryInfo = new DirectoryInfo(applicationBasePath);             do{               var solutionFileInfo = new FileInfo(Path.Combine(directoryInfo.FullName, slnName));                 if (solutionFileInfo.Exists){                     return Path.GetFullPath(Path.Combine(directoryInfo.FullName, solutionRelativePath, projectName));}directoryInfo = directoryInfo.Parent;}             while (directoryInfo.Parent != null);            throw new Exception($"Solution root could not be located using application root {applicationBasePath}.");}}
}

我们首先访问api/Values/Login，获取到Cookie，然后讲cookie附在httpclient的默认http头上，这样就能够成功访问需要授权的接口了

总结

通过上面演示，我们已经可以很大程度地模拟了整个api请求，让我们可以方便地一键调试目标接口，再也不用开浏览器或postman了。

附上演示项目地址：https://github.com/huanent/AspnetCoreFunctionalTestDemo

原文：http://www.cnblogs.com/huanent/p/7886282.html

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