IIS Express 8 - 最大允许长度答案

【问题标题】：IIS Express 8 - Max allowed lengthIIS Express 8 - 最大允许长度
【发布时间】：2015-06-16 13:26:17
【问题描述】：

如果下面的内容太长，我的问题是 Visual Studio 2013 中的 IIS Express 8 是否遵循 maxAllowedContentLength 属性，或者它是否具有阻止大型请求的某些覆盖值

在针对 Visual Studio 2013 调试一些 webapi 调用时，我收到此错误：

Maximum request length exceeded.

我搜索了互联网，一切似乎都指向这两个配置条目：

IIS 6-: maxRequestLength
IIS 7+: maxAllowedContentLength

为了安全起见，我已将这两个配置条目添加到我的 web.config 中，值为 4294967295。当我尝试调用控制器时，我仍然收到错误消息。

这让我觉得我正在向服务器发送大量数据，但 fiddler 告诉我：

Request Count:   1
Bytes Sent:      4,327,084      (headers:1,026; body:4,326,058)
Bytes Received:  3,808      (headers:434; body:3,374)

看看，4,327,084

我想到的下一个地方是我的服务器代码：

if (!Request.Content.IsMimeMultipartContent())
{
    throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
}

var provider = new MultipartFormDataStreamProvider(@"C:\tmp", Int32.MaxValue);

var task = Request.Content.ReadAsMultipartAsync(provider).ContinueWith(t =>
{
    if (t.IsFaulted || t.IsCanceled)
        throw t.Exception;   // <== This gets thrown

同样，请求的大小明显小于数据流提供者的缓冲区大小。

总之，我不知道发生了什么。这个请求相当大，但据我所知，这没有理由失败。这是由 VS13/IIS Exp8 引起的吗？还是我还缺少其他东西？

提前感谢您提供的任何帮助。

这是我说我会提供的配置条目

<requestLimits maxAllowedContentLength="4294967295" />

这里是完整的例外

System.IO.IOException: Error reading MIME multipart body part. ---> System.Web.HttpException: Maximum request length exceeded.
   at System.Web.HttpBufferlessInputStream.ValidateRequestEntityLength()
   at System.Web.HttpBufferlessInputStream.GetPreloadedContent(Byte[] buffer, Int32& offset, Int32& count)
   at System.Web.HttpBufferlessInputStream.BeginRead(Byte[] buffer, Int32 offset, Int32 count, AsyncCallback callback, Object state)
   at System.IO.Stream.<BeginEndReadAsync>b__d(Stream stream, ReadWriteParameters args, AsyncCallback callback, Object state)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncTrim[TInstance,TArgs](TInstance thisRef, TArgs args, Func`5 beginMethod, Func`3 endMethod)
   at System.IO.Stream.BeginEndReadAsync(Byte[] buffer, Int32 offset, Int32 count)
   at System.IO.Stream.ReadAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
   at System.Web.Http.WebHost.SeekableBufferedRequestStream.<ReadAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at System.Net.Http.HttpContentMultipartExtensions.<MultipartReadAsync>d__8.MoveNext()
   --- End of inner exception stack trace ---
   at System.Net.Http.HttpContentMultipartExtensions.<MultipartReadAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.GetResult()
   at System.Net.Http.HttpContentMultipartExtensions.<ReadAsMultipartAsync>d__0`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at BICWeb.webservices.controllers.FormsDesignerController.<Post>d__b.MoveNext() in c:\code\BIC_CORE\TRUNK\BIC\src\BICWeb\webservices\controllers\FormsDesignerController.cs:line 300

还有内部异常

System.Web.HttpException (0x80004005): Maximum request length exceeded.
   at System.Web.HttpBufferlessInputStream.ValidateRequestEntityLength()
   at System.Web.HttpBufferlessInputStream.GetPreloadedContent(Byte[] buffer, Int32& offset, Int32& count)
   at System.Web.HttpBufferlessInputStream.BeginRead(Byte[] buffer, Int32 offset, Int32 count, AsyncCallback callback, Object state)
   at System.IO.Stream.<BeginEndReadAsync>b__d(Stream stream, ReadWriteParameters args, AsyncCallback callback, Object state)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncTrim[TInstance,TArgs](TInstance thisRef, TArgs args, Func`5 beginMethod, Func`3 endMethod)
   at System.IO.Stream.BeginEndReadAsync(Byte[] buffer, Int32 offset, Int32 count)
   at System.IO.Stream.ReadAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken cancellationToken)
   at System.Web.Http.WebHost.SeekableBufferedRequestStream.<ReadAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at System.Net.Http.HttpContentMultipartExtensions.<MultipartReadAsync>d__8.MoveNext()

【问题讨论】：

您的数字太大，可能会被视为无效并被忽略。或者，上帝保佑，溢出。将它们设置为 10M，这足以满足此请求。并确保它们以字节为单位，谁知道呢。
只是提示，将throw t.Exception; 替换为t.Wait()。这样可以更好地处理错误并且不会破坏存储的堆栈。可能，您无论如何都不应该使用 ContinueWith 并使用 await。
@usr 是的，我使用 await 有一段时间了，但我处于“更改所有内容，看看是否有任何工作”模式
@usr 至于您的第一条评论，如果您溢出该条目，.Net 实际上会引发配置错误。从 MSDN，我输入的值是允许的最大值，它应该可以工作。
其实我忘记了一些重要的事情。发布完整的异常 ToString。这通常是我要求的第一件事，不知道为什么我忘记了。

标签： c# asp.net iis visual-studio-2013 iis-express

【解决方案1】：

让我们看看抛出的代码：

private void ValidateRequestEntityLength()
{
    if (!this._disableMaxRequestLength && (this.Length > this._maxRequestLength))
    {
        if (!(this._context.WorkerRequest is IIS7WorkerRequest))
        {
            this._context.Response.CloseConnectionAfterError();
        }
        throw new HttpException(SR.GetString("Max_request_length_exceeded"), null, 0xbbc);
    }
}

ctor 设置这些选项：

internal HttpBufferlessInputStream(HttpContext context, bool persistEntityBody, bool disableMaxRequestLength)
{
    this._context = context;
    this._persistEntityBody = persistEntityBody;
    this._disableMaxRequestLength = disableMaxRequestLength;
    HttpRuntimeSection httpRuntime = RuntimeConfig.GetConfig(this._context).HttpRuntime;
    this._maxRequestLength = httpRuntime.MaxRequestLengthBytes;
    this._fileThreshold = httpRuntime.RequestLengthDiskThresholdBytes;
    if (this._persistEntityBody)
    {
        this._rawContent = new HttpRawUploadedContent(this._fileThreshold, this._context.Request.ContentLength);
    }
    int contentLength = this._context.Request.ContentLength;
    this._remainingBytes = (contentLength > 0) ? contentLength : 0x7fffffff;
    this._length = contentLength;
}

你可以使用这个HttpRequest函数来禁用限制：

public Stream GetBufferlessInputStream(bool disableMaxRequestLength)
{
    return this.GetInputStream(false, disableMaxRequestLength);
}

如果您想知道字节限制是如何计算的，请反编译httpRuntime.MaxRequestLengthBytes。

【讨论】：

所以这一切都是在一个WebAPI控制器中完成的，所以Request实际上是一个HttpRequestMessage而不是一个HttpRequest。 HttpRequestMessage 似乎没有GetBufferlessInputStream 方法。
实际上，在这方面的一点帮助下，我能够让它工作。感谢所有的帮助！ stackoverflow.com/questions/25753248/…

【解决方案2】：

只是一个想法，但来自： http://www.smarterasp.net/support/kb/a1544/how-to-resolve-maximum-request-length-exceeded.aspx

“maxAllowedContentLength 以字节为单位，而 maxRequestLength 以千字节为单位”

检查它们是否都设置正确，然后重试

【讨论】：

无论哪种方式，都应该正确设置。我会用实际的配置值更新我的帖子