关于c＃：在单元测试中模拟IHttpContextAccessor

Mock IHttpContextAccessor in Unit Tests

我有一种使用IHttpContextAccessor获取标头值的方法

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public class HeaderConfiguration : IHeaderConfiguration
{
public HeaderConfiguration()
{

}

public string GetTenantId(IHttpContextAccessor httpContextAccessor)
{
return httpContextAccessor.HttpContext.Request.Headers["Tenant-ID"].ToString();
}
}

我正在测试GetBookByBookId方法

假设方法看起来像这样：

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public class Book
{
private readonly IHttpContextAccessor _httpContextAccessor;
private IHeaderConfiguration _headerConfiguration;
private string _tenantID;

public Book(IHeaderConfiguration headerConfiguration, IHttpContextAccessor httpContextAccessor){
var headerConfig = new HeaderConfiguration();
_httpContextAccessor = httpContextAccessor;
_tenantID = headerConfig.GetTenantId(_httpContextAccessor);
}

public Task<List<BookModel>> GetBookByBookId(string id){
//do something with the _tenantId
//...
}
}

这是我对GetBookByBookId方法的单元测试

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[Fact]
public void test_GetBookByBookId()
{
//Arrange

//Mock IHttpContextAccessor
var mockHttpContextAccessor = new Mock<IHttpContextAccessor>();

mockHttpContextAccessor.Setup(req => req.HttpContext.Request.Headers["Tenant-ID"].ToString()).Returns(It.IsAny<string>());
//Mock HeaderConfiguration
var mockHeaderConfiguration = new Mock<IHeaderConfiguration>();
mockHeaderConfiguration.Setup(x => x.GetTenantId(mockHttpContextAccessor.Object)).Returns(It.IsAny<string>());

var book = new Book( mockHttpContextAccessor.Object, mockHeaderConfiguration.Object);

var bookId ="100";

//Act
var result = book.GetBookByBookId(bookId);

//Assert
result.Result.Should().NotBeNull().And.
BeOfType<List<BookModel>>();
}

但是对于这一行：

1	mockHttpContextAccessor.Setup(req => req.HttpContext.Request.Headers["Tenant-ID"].ToString()).Returns(It.IsAny<string>());

它说

System.NotSupportedException: 'Type to mock must be an interface or an abstract or non-sealed class. '

我想知道使用标头值模拟IHttpContextAccessor的正确方法是什么？

您可以将DefaultHttpContext用作IHttpContextAccessor.HttpContext的后盾。省去您设置太多事情的麻烦

接下来，您不能将It.IsAny()用作Returns结果。它们只能在设置表达式中使用。

检查重构

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[Fact]
public async Task test_GetBookByBookId() {
//Arrange

//Mock IHttpContextAccessor
var mockHttpContextAccessor = new Mock<IHttpContextAccessor>();
var context = new DefaultHttpContext();
var fakeTenantId ="abcd";
context.Request.Headers["Tenant-ID"] = fakeTenantId;
mockHttpContextAccessor.Setup(_ => _.HttpContext).Returns(context);
//Mock HeaderConfiguration
var mockHeaderConfiguration = new Mock<IHeaderConfiguration>();
mockHeaderConfiguration
.Setup(_ => _.GetTenantId(It.IsAny<IHttpContextAccessor>()))
.Returns(fakeTenantId);

var book = new Book(mockHttpContextAccessor.Object, mockHeaderConfiguration.Object);

var bookId ="100";

//Act
var result = await book.GetBookByBookId(bookId);

//Assert
result.Should().NotBeNull().And.
BeOfType<List<BookModel>>();
}

由于实际上应该显式注入HeaderConfiguration时，它正在手动初始化HeaderConfiguration，所以被测类也可能存在问题。

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public Book(IHeaderConfiguration headerConfiguration, IHttpContextAccessor httpContextAccessor) {
_httpContextAccessor = httpContextAccessor;
_tenantID = headerConfiguration.GetTenantId(_httpContextAccessor);
}