超时已过。 - 在 ServiceStack 服务中使用 Db

Question

我在 ServiceStack 服务中使用 Db 属性来访问我的数据库，但我时不时地从 IIS 收到以下错误：

Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.

堆栈跟踪：

[InvalidOperationException: Timeout expired.  The timeout period elapsed prior to obtaining a connection from the pool.  This may have occurred because all pooled connections were in use and max pool size was reached.]
   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +6371713
   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +6372046
   System.Data.SqlClient.SqlConnection.Open() +300
   ServiceStack.OrmLite.OrmLiteConnection.Open() +44
   ServiceStack.OrmLite.OrmLiteConnectionFactory.OpenDbConnection() +132
   ServiceStack.ServiceInterface.Service.get_Db() +68

我已将Configure 方法中的ReuseScope 设置为ReuseScope.None，我相信这应该根据每个请求关闭连接？我在这里做错了什么？

public override void Configure(Container container)
{
    JsConfig.EmitCamelCaseNames = true;

    //Register all your dependencies
    ConfigureDb(container);

    //Set MVC to use the same Funq IOC as ServiceStack
    ControllerBuilder.Current.SetControllerFactory(new FunqControllerFactory(container));
}

配置数据库：

private static void ConfigureDb(Container container)
{
    var connectionString = ConfigurationManager.ConnectionStrings["AppDb"].ConnectionString;
    container.Register<IDbConnectionFactory>(c =>
        new OrmLiteConnectionFactory(connectionString, SqlServerDialect.Provider))
        .ReusedWithin(ReuseScope.None);

    using (var db = container.Resolve<IDbConnectionFactory>().Open())
    {
      // Do database seed/initialisation
    }
}

编辑

经过更多诊断，当我调用此服务方法时，似乎发生了几次刷新页面：

public Warranty Get(Warranty request)
    {
        var warranty = new Warranty();
        if (request.Id != default(int))
        {
            warranty = Db.Id<Warranty>(request.Id);
            warranty.WarrantyOrder = ResolveService<WarrantyOrderService>().Get(new WarrantyOrder { WarrantyId = warranty.Id });
            warranty.WarrantyStatus = ResolveService<WarrantyStatusService>().Get(new WarrantyStatus { Id = warranty.StatusId });
            warranty.WarrantyNotes = ResolveService<WarrantyNoteService>().Get(new WarrantyNotes { WarrantyId = warranty.Id });
            warranty.WarrantyDialogues = ResolveService<WarrantyDialogueService>().Get(new WarrantyDialogues { WarrantyId = warranty.Id });
            warranty.WarrantyCredit = ResolveService<WarrantyCreditService>().Get(new WarrantyCredit { WarrantyId = warranty.Id });
            warranty.WarrantyPhotos = ResolveService<WarrantyPhotoService>().Get(new WarrantyPhotos { WarrantyReference = warranty.WarrantyReference });
            warranty.WarrantyReport = ResolveService<WarrantyReportService>().Get(new WarrantyReport { WarrantyId = warranty.Id });
        }

        return warranty;
    }

我已根据下面的@mythz 答案更改了ConfigureDb：

    private static void ConfigureDb(Container container)
    {
        var connectionString = ConfigurationManager.ConnectionStrings["AppDb"].ConnectionString;
        container.Register<IDbConnectionFactory>(c => new OrmLiteConnectionFactory(connectionString, SqlServerDialect.Provider));
    }

该服务需要调用其他服务来填充我的Warranty 对象上的其他对象，我不确定如何改进？

Answer 1

IDbConnectionFactory 与所有连接管理器一样，是用于创建数据库连接的线程安全工厂，即它本身不是数据库连接。它应该被注册为单例。

默认ServiceStack的IOC(Funq)默认注册为Singleton，所以正确的注册只是：

container.Register<IDbConnectionFactory>(c =>
    new OrmLiteConnectionFactory(connectionString, SqlServerDialect.Provider));

解决服务

由于 ServiceStack 服务有可能利用托管资源，因此无论何时从另一个服务解析它们，都应该在 using 语句中使用它们，以便适当地处理它们，例如：

using (var orders = ResolveService<WarrantyOrderService>())
using (var status = ResolveService<WarrantyStatusService>())
{
    var warranty = new Warranty { 
        WarrantyOrder = orders.Get(new WarrantyOrder { WarrantyId = warranty.Id }),
        WarrantyStatus = status.Get(new WarrantyStatus { 
            WarrantyId = warranty.StatusId }),
       //etc
    }       

    return warranty; 
}