如何为我的单元测试创​​建 HttpContext？

Question

我正在努力模拟单元测试所需的HttpContext。

我已经使用SessionManager 接口将会话控制从我的Mvc 控制器中抽象出来，并使用一个名为CookieSessionManager 的类来实现它。 （早期开发阶段）。

CookieSessionManager 通过使用注入的单例 HttpContextAccessor（在 Startup.cs ConfigureServices 中）来使用 HttpContext。

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

在调试模式下手动测试可以正常工作

我为AccountController 类编写的MSUnit 测试与注入的MockSessionManager 类一起工作。

我遇到的真正问题是我为CookieSessionManager 班级编写的单元测试。我尝试设置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

但是对sessionManager.Login(CreateValidApplicationUser()); 的调用似乎没有设置IsAuthenticated 标志并且测试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;
}

测试名称：CookieSessionManager_Login_ValidUser_Authenticated_isTrue

：第 43 行测试结果：失败测试持续时间：0:00:00.0433169

结果 StackTrace：在 ClaimsWebAppTests.Identity.CookieSessionManagerTest.CookieSessionManager_Login_ValidUser_Authenticated_isTrue()

CookieSessionManagerTest.cs：第 46 行结果消息：Assert.IsTrue 失败。

我的代码

会话管理器

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，用HttpContext 进行测试几乎是不可能的。这是一个不使用任何接口的密封类，所以你不能模拟它。通常，最好的办法是抽象出与 HttpContext 一起使用的代码，然后只测试其他更特定于应用程序的代码。

您似乎已经通过HttpContextAccessor 完成了此操作，但您使用不正确。首先，您要暴露 HttpContext 实例，这几乎违背了整个目的。这个类应该能够自己返回类似User.Identity.IsAuthenticated的东西，比如：httpContextAccessor.IsAuthenticated。在内部，该属性将访问私有 HttpContext 实例并返回结果。

一旦您以这种方式使用它，您就可以模拟 HttpContextAccessor 以简单地返回您的测试所需的内容，而您不必担心为其提供 HttpContext 实例。

当然，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，但这些通常非常简单。例如，IsAuthenticated 的代码将类似于 return httpContext.User.Identity.IsAuthenticated。解决这个问题的唯一方法是，如果你用手指粗了一些东西，但编译器会警告你。

Answer 2

这并不能直接回答问题的上下文，但它提供了一种替代测试方法，当您开始使用它时，它会让生活变得更加轻松。

有一个可用于 ASP.NET Core 的集成测试包，有关它的文档可以在此处找到：

https://docs.asp.net/en/latest/testing/integration-testing.html

享受吧！

Answer 3

我为我的单元测试创​​建了这个助手功能，这让我可以测试那些需要部分 httpRequest 的特定方法。

public static IHttpContextAccessor GetHttpContext(string incomingRequestUrl, string host)
    {
        var context = new DefaultHttpContext();
        context.Request.Path = incomingRequestUrl;
        context.Request.Host = new HostString(host);

        //Do your thing here...

        var obj = new HttpContextAccessor();
        obj.HttpContext = context;
        return obj;
    }

Answer 4

您可以创建一个像下面这样继承 HttpContext 的测试类。并在需要的地方使用测试类。您可以在代码中添加缺少的实现。

public class TestHttpContext : HttpContext
{
    [Obsolete]
    public override AuthenticationManager Authentication
    {
        get { throw new NotImplementedException(); }
    }

    public override ConnectionInfo Connection
    {
        get { throw new NotImplementedException(); }
    }

    public override IFeatureCollection Features
    {
        get { throw new NotImplementedException(); }
    }

    public override IDictionary<object, object> Items
    {
        get { throw new NotImplementedException(); }
        set { throw new NotImplementedException(); }
    }

    public override HttpRequest Request
    {
        get { throw new NotImplementedException(); }
    }

    public override CancellationToken RequestAborted
    {
        get { throw new NotImplementedException(); }
        set { throw new NotImplementedException(); }
    }

    public override IServiceProvider RequestServices
    {
        get { throw new NotImplementedException(); }
        set { throw new NotImplementedException(); }
    }

    HttpResponse _response;
    public override HttpResponse Response
    {
        get
        {
            if (this._response == null)
            {
                this._response = new TestHttpResponse();
                this._response.StatusCode = 999;
            }

            return this._response;
        }
    }

    public override ISession Session
    {
        get { throw new NotImplementedException(); }
        set { throw new NotImplementedException(); }
    }

    public override string TraceIdentifier
    {
        get { throw new NotImplementedException(); }
        set { throw new NotImplementedException(); }
    }

    public override ClaimsPrincipal User
    {
        get { throw new NotImplementedException(); }
        set { throw new NotImplementedException(); }
    }

    public override WebSocketManager WebSockets
    {
        get { throw new NotImplementedException(); }
    }

    public override void Abort()
    {
        throw new NotImplementedException();
    }
}