引发内容流错误的.NET 5异常

Question

测试检查的代码中抛出的两个异常示例：

if (request.GroupId <= 0)
{
    throw new BadRequestException($"A valid {nameof(Data.Models.Group)} Id must be provided.");
}

var group = await Database.Groups.FindAsync(request.GroupId);
if (group == null)
{
    throw new EntityNotFoundException($"{nameof(Data.Models.Group)} not found.");
}

使用上述代码，当运行测试时，任何BadRequestException都会通过，但任何需要EntityNotFoundException类提供NotFound响应的测试都会产生以下错误：

Exception Message: 
        Test method MyProject.Test.Tests.Integration.Group.DeleteGroupTests.DeleteGroup_IdDoesNotExist_NotFound threw exception: 
        System.Net.Http.HttpRequestException: Error while copying content to a stream. ---> System.IO.IOException:  ---> MyProject.Data.Exceptions.EntityNotFoundException: Group not found.
      Stack Trace: 
        DeleteGroupCommandHandler.Handle(DeleteGroupCommand request, CancellationToken cancellationToken) line 40
        RequestExceptionProcessorBehavior`2.Handle(TRequest request, CancellationToken cancellationToken, RequestHandlerDelegate`1 next)
...

EntityNotFoundException-失败

public class EntityNotFoundException : ExceptionBase
{
    private static string DefaultMessageHeader => "Not found";

    public override HttpStatusCode StatusCode => HttpStatusCode.NotFound;

    public EntityNotFoundException(string message, string messageHeader = null)
            : base(message, messageHeader ?? DefaultMessageHeader) { }
}

public class BadRequestException : ExceptionBase
{
    private static string DefaultMessageHeader => "Bad Request";

    public override HttpStatusCode StatusCode => HttpStatusCode.BadRequest;

    public BadRequestException(string message, string messageHeader = null)
            : base(message, messageHeader ?? DefaultMessageHeader) { }
}

测试：

// FAILS
[DataTestMethod]
[DataRow(int.MaxValue)]
public async Task DeleteGroup_IdDoesNotExist_NotFound(int groupId)
{
    var response = await Client.DeleteAsync($"/api/groups/{groupId}");
    response.StatusCode.Should().Be(HttpStatusCode.NotFound);
}

// PASSES
[DataTestMethod]
[DataRow(0)]
[DataRow(-1)]
public async Task DeleteGroup_InvalidId_BadRequest(int groupId)
{
    var response = await Client.DeleteAsync($"/api/groups/{groupId}");
    response.StatusCode.Should().Be(HttpStatusCode.BadRequest);
}

Answer 1

找到了修复测试的解决方案，但仍然不确定为什么错误只发生在EntityNotFoundException异常类而不发生其他异常类。

如果有人知道为什么下面的代码修复了失败的测试，我很想听听。

解决方案是指定HttpCompletionOption.ResponseHeadersRead标志，该标志在DeleteAsync中不可用，因此切换到SendAsync。

using var response = await Client.DeleteAsync($"/api/groups/{groupId}");

using var response = await Client.SendAsync(new HttpRequestMessage(HttpMethod.Delete, $"/api/groups/{groupId}"), HttpCompletionOption.ResponseHeadersRead);