c# - 如何为单元测试创​​建 HttpContext？

Question

我正在努力为我的单元测试模拟所需的 HttpContext。

我已经使用 SessionManager 接口(interface)从我的 Mvc Controller 中抽象出对 session 的控制，并使用名为 CookieSessionManager 的类实现了它。 (早期开发阶段)。

CookieSessionManager 通过注入(inject)的单例 HttpContextAccessor(在 Startup.cs ConfigureServices 中)使用 HttpContext。

我正在使用在 Startup.cs 中使用 app.UseCookieAuthentication 设置的 Cookie 身份验证。

在 Debug模式下手动测试它会按预期工作

我为我的 AccountController 类编写的 MSUnit 测试与注入(inject)的 MockSessionManager 类一起工作。

我遇到的真正问题是我为我的 CookieSessionManager 类编写的单元测试。我已尝试设置 HttpContext，如下所示；

[TestClass]
public class CookieSessionManagerTest
{
    private IHttpContextAccessor contextAccessor;
    private HttpContext context;
    private SessionManager sessionManager;

    [TestInitialize]
    public void Setup_CookieSessionManagerTest()
    {
        context = new DefaultHttpContext();

        contextAccessor = new HttpContextAccessor();

        contextAccessor.HttpContext = context;

        sessionManager = new CookieSessionManager(contextAccessor);
    }

错误

但是调用 sessionManager.Login(CreateValidApplicationUser()); 似乎没有设置 IsAuthenticated 标志和测试 CookieSessionManager_Login_ValidUser_Authenticated_isTrue失败。

[TestMethod]
public void CookieSessionManager_Login_ValidUser_Authenticated_isTrue()
{
    sessionManager.Login(CreateValidApplicationUser());

    Assert.IsTrue(sessionManager.isAuthenticated());
}

public ApplicationUser CreateValidApplicationUser()
{
    ApplicationUser applicationUser = new ApplicationUser();

    applicationUser.UserName = "ValidUser";

    //applicationUser.Password = "ValidPass";

    return applicationUser;
}

Test Name: CookieSessionManager_Login_ValidUser_Authenticated_isTrue

: line 43 Test Outcome: Failed Test Duration: 0:00:00.0433169

Result StackTrace: at ClaimsWebAppTests.Identity.CookieSessionManagerTest.CookieSessionManager_Login_ValidUser_Authenticated_isTrue()

CookieSessionManagerTest.cs:line 46 Result Message: Assert.IsTrue failed.

我的代码

session 管理器

using ClaimsWebApp.Models;

namespace ClaimsWebApp.Identity
{
    public interface SessionManager
    {
        bool isAuthenticated();

        void Login(ApplicationUser applicationUser);

        void Logout();
    }
}

CookieSessionManager

using ClaimsWebApp.Identity;
using ClaimsWebApp.Models;
using Microsoft.AspNetCore.Http;
using System;
using System.Collections.Generic;
using System.Security.Claims;

namespace ClaimsWebApp
{
    public class CookieSessionManager : SessionManager
    {
        private List<ApplicationUser> applicationUsers;
        private IHttpContextAccessor ContextAccessor;
        private bool IsAuthenticated;

        public CookieSessionManager(IHttpContextAccessor contextAccessor)
        {
            this.IsAuthenticated = false;

            this.ContextAccessor = contextAccessor;

            IsAuthenticated = ContextAccessor.HttpContext.User.Identity.IsAuthenticated;

            applicationUsers = new List<ApplicationUser>();

            applicationUsers.Add(new ApplicationUser { UserName = "ValidUser" });
        }
        public bool isAuthenticated()
        {
            return IsAuthenticated;
        }

        public void Login(ApplicationUser applicationUser)
        {
            if (applicationUsers.Find(m => m.UserName.Equals(applicationUser.UserName)) != null)
            {
                var identity = new ClaimsIdentity(new[] {
                new Claim(ClaimTypes.Name, applicationUser.UserName)
                },
                "MyCookieMiddlewareInstance");

                var principal = new ClaimsPrincipal(identity);

                ContextAccessor.HttpContext.Authentication.SignInAsync("MyCookieMiddlewareInstance", principal);

                IsAuthenticated = ContextAccessor.HttpContext.User.Identity.IsAuthenticated;
            }
            else
            {
                throw new Exception("User not found");
            }
        }

        public void Logout()
        {
            ContextAccessor.HttpContext.Authentication.SignOutAsync("MyCookieMiddlewareInstance");

            IsAuthenticated = ContextAccessor.HttpContext.User.Identity.IsAuthenticated;
        }
    }
}

Startup.cs

using ClaimsWebApp.Identity;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;

namespace ClaimsWebApp
{
    public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit http://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
            services.AddScoped<SessionManager, CookieSessionManager>();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole();

            app.UseCookieAuthentication(new CookieAuthenticationOptions()
            {
                AuthenticationScheme = "MyCookieMiddlewareInstance",
                LoginPath = new PathString("/Account/Unauthorized/"),
                AccessDeniedPath = new PathString("/Account/Forbidden/"),
                AutomaticAuthenticate = true,
                AutomaticChallenge = true
            });

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Account}/{action=Login}/{id?}");
            });
        }
    }
}

CookieSessionManagerTest.cs

using ClaimsWebApp;
using ClaimsWebApp.Identity;
using ClaimsWebApp.Models;
using Microsoft.AspNetCore.Http;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace ClaimsWebAppTests.Identity
{
    [TestClass]
    public class CookieSessionManagerTest
    {
        private IHttpContextAccessor contextAccessor;
        private HttpContext context;
        private SessionManager sessionManager;

        [TestInitialize]
        public void Setup_CookieSessionManagerTest()
        {
            context = new DefaultHttpContext();

            contextAccessor = new HttpContextAccessor();

            contextAccessor.HttpContext = context;

            sessionManager = new CookieSessionManager(contextAccessor);
        }

        [TestMethod]
        public void CookieSessionManager_Can_Be_Implemented()
        {
            Assert.IsInstanceOfType(sessionManager, typeof(SessionManager));
        }


        [TestMethod]
        public void CookieSessionManager_Default_Authenticated_isFalse()
        {
            Assert.IsFalse(sessionManager.isAuthenticated());
        }

        [TestMethod]
        public void CookieSessionManager_Login_ValidUser_Authenticated_isTrue()
        {
            sessionManager.Login(CreateValidApplicationUser());

            Assert.IsTrue(sessionManager.isAuthenticated());
        }

        public ApplicationUser CreateValidApplicationUser()
        {
            ApplicationUser applicationUser = new ApplicationUser();

            applicationUser.UserName = "ValidUser";

            //applicationUser.Password = "ValidPass";

            return applicationUser;
        }

        public ApplicationUser CreateInValidApplicationUser()
        {
            ApplicationUser applicationUser = new ApplicationUser();

            applicationUser.UserName = "InValidUser";

            //applicationUser.Password = "ValidPass";

            return applicationUser;
        }
    }
}

Answer 1

不幸的是，几乎不可能用 HttpContext 进行测试。它是一个不使用任何接口(interface)的密封类，因此您不能模拟它。通常，最好的办法是抽象出使用 HttpContext 的代码，然后只测试其他更特定于应用程序的代码。

看起来您已经通过 HttpContextAccessor 完成了此操作，但您没有正确使用它。首先，您公开了 HttpContext 实例，这几乎违背了整个目的。此类应该能够自行返回类似 User.Identity.IsAuthenticated 的内容，例如:httpContextAccessor.IsAuthenticated。在内部，该属性将访问私有(private) HttpContext 实例并只返回结果。

一旦你以这种方式使用它，你就可以模拟 HttpContextAccessor 来简单地返回你测试所需的内容，你不必担心为它提供一个 HttpContext 实例。

诚然，这意味着仍有一些未经测试的代码，即与 HttpContext 一起使用的访问器方法，但这些代码通常非常简单。例如，IsAuthenticated 的代码类似于return httpContext.User.Identity.IsAuthenticated。你要搞砸的唯一方法是如果你粗暴地指责某些东西，但编译器会警告你。