c# - Stream 意外结束，内容可能已被另一个组件读取

Question

我遇到了一些奇怪的问题，只有 1 个用户(假设有 50 个用户)遇到过这个问题。据我所知他正在使用 Chrome

当他上传文件时，流意外结束，内容可能已被另一个组件读取。被抛出

这是我的端点:

[HttpPost]
public async Task<JsonResult> UploadFile(IFormFile file, int type, string otherParam)

问题是我有记录每个请求的中间件，因此它正在读取请求并将正文位置设置为 0

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Controllers;
using Microsoft.AspNetCore.Mvc.Filters;
using Services;
using System;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http.Internal;
using Serilog;
using Newtonsoft.Json;
using Common.Users;

public class LoggerMiddleware
{
    private readonly RequestDelegate next;

    public LoggerMiddleware(RequestDelegate next)
    {
        this.next = next;
    }

    public async Task Invoke(HttpContext ctx)
    {
        var request = await FormatRequest(ctx.Request, ctx);
        Log.Information(request);
        await next(ctx);
    }

    //hack
    private string[] endpoints_with_passwords = new string[] { "/Account/ChangePassword", "/Login" };

    private async Task<string> FormatRequest(HttpRequest request, HttpContext ctx)
    {
        Log.Information("Entering Logging Middleware");

        request.EnableRewind();
        var length = Convert.ToInt32(request.ContentLength);

        // in order to prevent having content of large files in logs...
        if (length > 30000)
            return $"file with length: {length} sent by User: '{ctx?.User?.Identity?.Name}'";

        var buffer = new byte[length];
        await request.Body.ReadAsync(buffer, 0, buffer.Length);
        var bodyAsText = Encoding.UTF8.GetString(buffer);

        // "hack" in order to do not log passwords
        if (endpoints_with_passwords.Contains(request.Path.Value))
        {
            Log.Information("endpoints with password");
            try
            {
                var data = JsonConvert.DeserializeObject<LoginModel>(bodyAsText);
                var ip = request.HttpContext.Connection.RemoteIpAddress;
                bodyAsText = $"IP: {ip} - UserName: {data?.UserName}";
            }
            catch (Exception ex)
            {
                EmailService.SendExceptionEmail(ex);
                Log.Error(ex.Message);
            }
        }

        Log.Information("Body Position = 0");
        request.Body.Position = 0;

        return $"User: '{ctx?.User?.Identity?.Name}' {Environment.NewLine} {request.Scheme} {request.Host}{request.Path} {Environment.NewLine} {request.QueryString} {Environment.NewLine} {bodyAsText}";
    }
}

我以为早点回来

if (length > 30000)
    return $"file with length: {length} sent by User: '{ctx?.User?.Identity?.Name}'";

可能会导致问题，但是当文件太大时，我会收到请求正文太大。

所以这是不同的错误

这是显示差异的 SeriLog

日志:其他用户上传工作正常:

2020-01-22 14:35:13.003 +01:00 [INF] User: 'A' 
 http localhost:5004/File/AddAttachment/1/attachment
 ?_=1579699970169 
 ------WebKitFormBoundarywlRNAu9AuOB6xBUD
Content-Disposition: form-data; name="file"; filename="some.docx"
Content-Type: application/vnd.openxmlformats-officedocument.wordprocessingml.document
2020-01-22 14:35:13.083 +01:00 [INF] Route matched with {action = "AddAttachment", controller = "File"}. Executing controller action with signature System.Threading.Tasks.Task`1[Microsoft.AspNetCore.Mvc.JsonResult] AddAttachment(Microsoft.AspNetCore.Http.IFormFile, Int32, System.String) on controller Controllers.FileController (APP).
2020-01-22 14:35:13.083 +01:00 [INF] Authorization was successful.

已损坏，由(上述)某个特定用户发送:

2020-01-24 16:29:24.677 +01:00 [INF] User: 'B' 
 http localhost:5004/File/AddAttachment/1/attachment
 ?_=1579711474176 
2020-01-24 16:29:24.677 +01:00 [INF] Route matched with {action = "AddAttachment", controller = "File"}. Executing controller action with signature System.Threading.Tasks.Task`1[Microsoft.AspNetCore.Mvc.JsonResult] AddAttachment(Microsoft.AspNetCore.Http.IFormFile, Int32, System.String) on controller Controllers.FileController (APP).
2020-01-24 16:29:24.677 +01:00 [INF] Authorization was successful.
2020-01-24 16:29:27.381 +01:00 [ERR] 01/24/2020 16:29:25: Exception! (...) Unexpected end of Stream, the content may have already been read by another component.

有人知道可能会出什么问题吗？或者如何调试？

.NET Core 2.1

我们通过 JS 发布这些文件。

编辑:GH 上的问题 https://github.com/dotnet/aspnetcore/issues/18087

Answer 1

该问题可能是由用户中断文件上传引起的。你为什么不尝试重现这样的问题呢？

1. 开始上传大文件
2. 关闭浏览器标签
3. 预期错误