EF核心-System.InvalidOperationException：ExecuteReader需要打开且可用的连接。连接的当前状态为关闭 [英] EF Core - System.InvalidOperationException: ExecuteReader requires an open and available Connection. The connection's current state is closed

问题描述

我正在运行带有Entity Framework Core的ASP.NET Core 1.0 Web应用程序。当应用程序运行了一段时间（24-48小时）后，该应用程序在对任何端点或静态资源的每个请求上开始崩溃，并抛出错误 System.InvalidOperationException：ExecuteReader需要打开且可用的Connection。连接的当前状态已关闭。我只能通过重新启动应用程序池来从中恢复。

I'm running an ASP.NET Core 1.0 web app with Entity Framework Core. When the app has been running for a while (24 - 48 hours), the app starts crashing on every request to any endpoint or static resource throwing the error System.InvalidOperationException: ExecuteReader requires an open and available Connection. The connection's current state is closed. I can only recover from this by restarting the App Pool.

我正在像这样配置实体框架：

I am configuring Entity Framework like this:

Startup.cs

Startup.cs

public void ConfigureServices(IServiceCollection services)
{
        services.AddDbContext<ApplicationDbContext>(options =>
            options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));   
}

我正在使用这样的扩展方法在owin管道中加载数据：

I am loading data in the owin pipeline with an extension method like this like this:

Startup.cs

Startup.cs

app.LoadTenantData();

AppBuilderExtensions.cs：

AppBuilderExtensions.cs:

public static void LoadTenantData(this IApplicationBuilder app)
    {
        app.Use(async (context, next) =>
        {
            var dbContext = app.ApplicationServices.GetService<ApplicationDbContext>();        
            var club = dbContext.Clubs.Single(c => c.Id == GetClubIdFromUrl(context));
            context.Items[PipelineConstants.ClubKey] = club;
            await next();
        });
    }

由于错误仅在应用程序已运行很长时间时发生，很难复制，但是我认为它与EF错误地打开和关闭连接有关。

Since the error only occurs when the app has been running for a long time, it is hard to reproduce, but I'm assuming it has something to do with EF opening and closing connections incorrectly.

我该如何调试呢？我使用EF是否不正确？

How can I go about to debug this? Am I using EF incorrectly?

推荐答案

我遇到了同样的问题。

I got same issue.

我认为同一dbcontext实例可能被多个线程同时使用。

I think it is likely that the same dbcontext instance is being used concurrently by multiple threads.

需要这个：
services.AddDbContext< ApplicationDbContext>（options => options.UseSqlServer（Configuration.GetConnectionString（ DefaultConnection）），ServiceLifetime.Transient）;

有一个问题。
https://github.com/aspnet/EntityFramework/issues/6491

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