返回IHttpActionResult时，如何对Web API操作方法进行单元测试？

假设这是我的操作方法

public IHttpActionResult Get(int id)
{
    var status = GetSomething(id);
    if (status)
    {
        return Ok();
    }
    else
    {
        return NotFound();
    }
}

测试将

var httpActionResult = controller.Get(1);

此后如何检查我的http状态代码？

这Ok()只是OkResult将响应状态设置为HttpStatusCode.Ok... 的类型的帮助器，因此您可以仅检查操作结果的实例是否为OkResult...一些示例（用编写XUnit）：

// if your action returns: NotFound()
IHttpActionResult actionResult = valuesController.Get(10);
Assert.IsType<NotFoundResult>(actionResult);

// if your action returns: Ok()
actionResult = valuesController.Get(11);
Assert.IsType<OkResult>(actionResult);

// if your action was returning data in the body like: Ok<string>("data: 12")
actionResult = valuesController.Get(12);
OkNegotiatedContentResult<string> conNegResult = Assert.IsType<OkNegotiatedContentResult<string>>(actionResult);
Assert.Equal("data: 12", conNegResult.Content);

// if your action was returning data in the body like: Content<string>(HttpStatusCode.Accepted, "some updated data");
actionResult = valuesController.Get(13);
NegotiatedContentResult<string> negResult = Assert.IsType<NegotiatedContentResult<string>>(actionResult);
Assert.Equal(HttpStatusCode.Accepted, negResult.StatusCode);
Assert.Equal("some updated data", negResult.Content);

该死的问题了

当前的答案都依赖于将响应对象转换为已知类型。不幸的是，在没有深入了解控制器实现的情况下，响应似乎没有可用的层次结构或隐式转换路径才能使其正常工作。考虑以下：

public class MixedCodeStandardController : ApiController {

    public readonly object _data = new Object();

    public IHttpActionResult Get() {
        return Ok(_data);
    }

    public IHttpActionResult Get(int id) {
        return Content(HttpStatusCode.Success, _data);
    }
}

测试课程：

var testController = new MixedCodeStandardController();

var getResult = testController.Get();
var posRes = getResult as OkNegotiatedContentResult<object>;
Assert.IsType<OkNegotiatedContentResult<object>>(getResult);
Assert.AreEqual(HttpStatusCode.Success, posRes.StatusCode);
Assert.AreEqual(testController._data, posRes.Content);

var idResult = testController.Get(1);
var oddRes = getResult as OkNegotiatedContentResult<object>; // oddRes is null
Assert.IsType<OkNegotiatedContentResult<object>>(idResult); // throws failed assertion
Assert.AreEqual(HttpStatusCode.Success, oddRes.StatusCode); // throws for null ref
Assert.AreEqual(testController._data, oddRes.Content); // throws for null ref

从黑匣子外部，响应流基本相同。测试必须知道控制器如何以这种方式实现return调用来对其进行测试。

而是使用IHttpActionResult返回的HttpResponseMessage对象。这样可以确保测试即使在控制器代码可能不一致的情况下也可以保持一致：

var testController = new MixedCodeStandardController();

var getResult = testController.Get();
var getResponse = getResult.ExecuteAsync(CancellationToken.None).Result;
Assert.IsTrue(getResponse.IsSuccessStatusCode);
Assert.AreEqual(HttpStatusCode.Success, getResponse.StatusCode);

var idResult = testController.Get(1);
var idResponse = idResult.ExecuteAsync(CancellationToken.None).Result;
Assert.IsTrue(idResponse.IsSuccessStatusCode);
Assert.AreEqual(HttpStatusCode.Success, idResponse.StatusCode);

这是Kiran Challa接受的答案，适用于NUnit。

var valuesController = controller;
// if your action returns: NotFound()
IHttpActionResult actionResult = valuesController.Get(10);
var notFoundRes = actionResult as NotFoundResult;
Assert.IsNotNull(notFoundRes);

// if your action returns: Ok()
actionResult = valuesController.Get(11);
var posRes = actionResult as OkResult;
Assert.IsNotNull(posRes);

// if your action was returning data in the body like: Ok<string>("data: 12")
actionResult = valuesController.Get(12);
var conNegResult = actionResult as OkNegotiatedContentResult<string>;
Assert.IsNotNull(conNegResult);
Assert.AreEqual("data: 12", conNegResult.Content);

// if your action was returning data in the body like: Content<string>(HttpStatusCode.Accepted, "some updated data");
actionResult = valuesController.Get(13);
var negResult = actionResult as NegotiatedContentResult<string>;
Assert.IsNotNull(negResult);
Assert.AreEqual(HttpStatusCode.Accepted, negResult.StatusCode);
Assert.AreEqual("some updated data", negResult.Content);

https://docs.microsoft.com/zh-cn/aspnet/web-api/overview/testing-and-debugging/unit-testing-controllers-in-web-api#testing-actions-that-return-ihttpactionresult

Assert.IsInstanceOfType（httpActionResult，typeof（OkResult））;

如果IHttpActionResult包含JSON对象，例如{“ token”：“ A”}，我们可以使用以下代码。

        var result = usercontroller.GetLogin("user", "password");
        Assert.IsInstanceOfType(result, typeof(OkNegotiatedContentResult<Dictionary<string,string>>));
        var content = result as OkNegotiatedContentResult<Dictionary<string, string> >;
        Assert.AreEqual("A", content.Content["token"]);

经过几个小时的研究和尝试，我终于找到了如何完全测试返回IHttpActionResult并使用OWIN中间件和ASP.NET Identity的默认实现的Web API 2方法的方法。

我将Get()在以下测试该方法ApiController：

public class AccountController : ApiController
{
    private ApplicationUserManager _userManager;
    public ApplicationUserManager UserManager => _userManager ?? HttpContext.Current.GetOwinContext().GetUserManager<ApplicationUserManager>();

    [Route("api/account"), HttpGet]
    public async Task<IHttpActionResult> Get()
    {
        var user = await UserManager.FindByIdAsync(User.Identity.GetUserId());
        if (user == null)
        {
            ModelState.AddModelError(ModelStateConstants.Errors, "Account not found! Try logging out and in again.");
            return BadRequest(ModelState);
        }

        var roles = await UserManager.GetRolesAsync(user.Id);

        var accountModel = new AccountViewModel
        {
            FullName = user.FullName,
            Email = user.Email,
            Phone = user.PhoneNumber,
            Organization = user.Organization.Name,
            Role = string.Join(", ", roles)
        };

        return Ok(accountModel);
    }

    protected override void Dispose(bool disposing)
    {
        if (disposing)
        {
            if (_userManager != null)
            {
                _userManager.Dispose();
                _userManager = null;
            }
        }

        base.Dispose(disposing);
    }
}

从所有测试类都将继承的基类开始：

public class BaseTest
{
    protected static User CurrentUser;
    protected static IList<string> Roles;

    public BaseTest()
    {
        var email = "unit@test.com";

        CurrentUser = new User
        {
            FullName = "Unit Tester",
            Email = email,
            UserName = email,
            PhoneNumber = "123456",
            Organization = new Organization
            {
                Name = "Test Organization"
            }
        };

        Roles = new List<string>
        {
            "Administrator"
        };
    }

    protected void InitializeApiController(ApiController apiController)
    {
        //Init fake controller Http and Identity data
        var config = new HttpConfiguration();
        var request = new HttpRequestMessage();
        var routeData = new HttpRouteData(new HttpRoute(""));
        apiController.ControllerContext = new HttpControllerContext(config, routeData, request)
        {
            Configuration = config
        };

        apiController.User = new GenericPrincipal(new GenericIdentity(""), new[] { "" });

        //Initialize Mocks
        var appUserMgrMock = GetMockedApplicationUserManager();
        var appSignInMgr = GetMockedApplicationSignInManager(appUserMgrMock);
        var appDbContext = GetMockedApplicationDbContext();

        //Configure HttpContext.Current.GetOwinContext to return mocks
        var owin = new OwinContext();
        owin.Set(appUserMgrMock.Object);
        owin.Set(appSignInMgr.Object);
        owin.Set(appDbContext.Object);

        HttpContext.Current = new HttpContext(new HttpRequest(null, "http://test.com", null), new HttpResponse(null));
        HttpContext.Current.Items["owin.Environment"] = owin.Environment;
    }

    private static Mock<ApplicationSignInManager> GetMockedApplicationSignInManager(Mock<ApplicationUserManager> appUserMgrMock)
    {
        var authMgr = new Mock<Microsoft.Owin.Security.IAuthenticationManager>();
        var appSignInMgr = new Mock<ApplicationSignInManager>(appUserMgrMock.Object, authMgr.Object);

        return appSignInMgr;
    }

    private Mock<ApplicationUserManager> GetMockedApplicationUserManager()
    {
        var userStore = new Mock<IUserStore<User>>();
        var appUserMgr = new Mock<ApplicationUserManager>(userStore.Object);
        appUserMgr.Setup(aum => aum.FindByIdAsync(It.IsAny<string>())).ReturnsAsync(CurrentUser);
        appUserMgr.Setup(aum => aum.GetRolesAsync(It.IsAny<string>())).ReturnsAsync(Roles);

        return appUserMgr;
    }

    private static Mock<ApplicationDbContext> GetMockedApplicationDbContext()
    {
        var dbContext = new Mock<ApplicationDbContext>();
        dbContext.Setup(dbc => dbc.Users).Returns(MockedUsersDbSet);

        return dbContext;
    }

    private static IDbSet<User> MockedUsersDbSet()
    {
        var users = new List<User>
        {
            CurrentUser,
            new User
            {
                FullName = "Testguy #1",
                Email = "test@guy1.com",
                UserName = "test@guy1.com",
                PhoneNumber = "123456",
                Organization = new Organization
                {
                    Name = "Test Organization"
                }
            }
        }.AsQueryable();

        var usersMock = new Mock<DbSet<User>>();
        usersMock.As<IQueryable<User>>().Setup(m => m.Provider).Returns(users.Provider);
        usersMock.As<IQueryable<User>>().Setup(m => m.Expression).Returns(users.Expression);
        usersMock.As<IQueryable<User>>().Setup(m => m.ElementType).Returns(users.ElementType);
        usersMock.As<IQueryable<User>>().Setup(m => m.GetEnumerator()).Returns(users.GetEnumerator);

        return usersMock.Object;
    }
}

该InitializeApiController方法包含肉和土豆。

现在我们可以为AccountController以下内容编写测试了：

public class AccountControllerTests : BaseTest
{
    private readonly AccountController _accountController;

    public AccountControllerTests()
    {
        _accountController = new AccountController();
        InitializeApiController(_accountController);
    }

    [Test]
    public async Task GetShouldReturnOk()
    {
        var result = await _accountController.Get();
        var response = await result.ExecuteAsync(CancellationToken.None);
        Assert.AreEqual(HttpStatusCode.OK, response.StatusCode);
    }
}

为了使一切正常工作，您需要安装一堆Microsoft.OWIN.*和Microsoft.AspNet.*软件包，我将packages.config在此处粘贴：

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="Castle.Core" version="4.3.1" targetFramework="net472" />
  <package id="EntityFramework" version="6.2.0" targetFramework="net472" />
  <package id="Microsoft.AspNet.Identity.Core" version="2.2.2" targetFramework="net472" />
  <package id="Microsoft.AspNet.Identity.EntityFramework" version="2.2.2" targetFramework="net472" />
  <package id="Microsoft.AspNet.Identity.Owin" version="2.2.2" targetFramework="net472" />
  <package id="Microsoft.AspNet.WebApi.Client" version="5.2.7" targetFramework="net472" />
  <package id="Microsoft.AspNet.WebApi.Core" version="5.2.7" targetFramework="net472" />
  <package id="Microsoft.AspNet.WebApi.Owin" version="5.2.7" targetFramework="net472" />
  <package id="Microsoft.Owin" version="4.0.1" targetFramework="net472" />
  <package id="Microsoft.Owin.Host.SystemWeb" version="4.0.1" targetFramework="net472" />
  <package id="Microsoft.Owin.Security" version="4.0.1" targetFramework="net472" />
  <package id="Microsoft.Owin.Security.Cookies" version="4.0.1" targetFramework="net472" />
  <package id="Microsoft.Owin.Security.OAuth" version="4.0.1" targetFramework="net472" />
  <package id="Moq" version="4.10.1" targetFramework="net472" />
  <package id="Newtonsoft.Json" version="12.0.1" targetFramework="net472" />
  <package id="NUnit" version="3.11.0" targetFramework="net472" />
  <package id="Owin" version="1.0" targetFramework="net472" />
  <package id="System.Runtime.CompilerServices.Unsafe" version="4.5.2" targetFramework="net472" />
  <package id="System.Threading.Tasks.Extensions" version="4.5.2" targetFramework="net472" />
</packages>

测试非常简单，但是证明一切正常:-)

测试愉快！