C#缺少content-type边界

Question

我正在使用RestEase客户端库从一个服务向另一个服务发起请求。它的接口形式如下：

public interface IImportService1ApiClient
{
    [Put]
    [Header("Content-Type", "multipart/form-data")]
    Task<CreateValidationJobResponse> ImportZip([Body] byte[] zipByteArray);
}

并且终端点 (.Net Core 1.1, Web Api):

    [HttpPut()]
    [Consumes("multipart/form-data")]
    public async Task<IActionResult> ImportZip()
    {
         var zipFile = HttpContext.Request.Form.Files.FirstOrDefault();
     ...

我可以发出请求，但是当我尝试从文件集合中获取文件时，会出现异常。

System.IO.InvalidDataException: Missing content-type boundary.

堆栈跟踪：

 Connection id "0HL8CNQ0E4M94": An unhandled exception was thrown by the application.
System.IO.InvalidDataException: Missing content-type boundary.
   at Microsoft.AspNetCore.Http.Features.FormFeature.GetBoundary(MediaTypeHeaderValue contentType, Int32 lengthLimit)
   at Microsoft.AspNetCore.Http.Features.FormFeature.<InnerReadFormAsync>d__18.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Http.Features.FormFeature.ReadForm()
   at RODIX.Tacs.Services.Import.Api.Controllers.TacsLegacyImportController.<ImportZip>d__3.MoveNext() in C:\Users\borov\Source\Repos\Rodix.Tacs\Rodix.Tacs\services\RODIX.ImportService\src\RODIX.Tacs.Services.Import.Api\Controllers\TacsLegacyImportController.cs:line 32
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeActionMethodAsync>d__27.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeNextActionFilterAsync>d__25.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ActionExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeNextResourceFilter>d__22.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ResourceExecutedContext context)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeAsync>d__20.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Builder.RouterMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware`1.<Invoke>d__18.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware`1.<Invoke>d__18.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at IdentityServer4.AccessTokenValidation.IdentityServerAuthenticationMiddleware.<Invoke>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Hosting.Internal.RequestServicesContainerMiddleware.<Invoke>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Frame`1.<RequestProcessingAsync>d__2.MoveNext()

但是使用Postman进行相同操作时一切正常。那么boundary到底是什么，为什么我会缺失它，如果确实需要如何添加呢？

- Roman Borovets

---

或许这条评论会有所帮助。 - NightOwl888

当未设置请求头内容类型时，请求将无法通过。使用[Consumes("multipart/form-data")]属性，否则将会出现缺少内容类型的异常。@NightOwl888 - Roman Borovets

@NightOwl888 你是对的。我们不能修改那个头文件。 - FindOutIslamNow

Answer 1

如果你只是要上传一个文件，为什么不直接获取Request.Body Stream呢：

[HttpPost()]
[Consumes("application/zip")]
[Consumes("application/octet-stream")]
public async Task<IActionResult> ImportZip()
{
    using (var stream = new MemoryStream())
    {
        await Request.Body.CopyToAsync(stream);
    }

    // do whatever with the file...
}

我认为你也可以这样定义：

[HttpPost()]
[Consumes("application/zip")]
[Consumes("application/octet-stream")]
public async Task<IActionResult> ImportZip([FromBody] Stream bodyStream)
{
    using (var stream = new MemoryStream())
    {
        await bodyStream.CopyToAsync(stream);
    }

    // do whatever with the file...
}

- Rebecca