[SqlSugar] 一定时间web页面不操作后报错 返回

问题：

    目前不清楚是偶发性问题还是其他问题，项目是从以前SqlServer数据库改为mysql8.0，我自己在开发使用中并没触发过这个错误，但是听测试说经常会出现，特别是当页面不操作（没有请求数据）一段时间后（一小时左右）就会出现

错误日志:

数据库连接错误
   at SqlSugar.SqlSugarRepository`1..ctor(IServiceProvider serviceProvider, ISqlSugarClient context)
   at ResolveService(ILEmitResolverBuilderRuntimeContext , ServiceProviderEngineScope )
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.GetService(Type serviceType, ServiceProviderEngineScope serviceProviderEngineScope)
   at Microsoft.Extensions.DependencyInjection.ActivatorUtilities.GetService(IServiceProvider sp, Type type, Type requiredBy, Boolean isDefaultParameterRequired)
   at lambda_method598(Closure , IServiceProvider , Object[] )
   at Microsoft.AspNetCore.Mvc.Controllers.ControllerFactoryProvider.<>c__DisplayClass6_0.<CreateControllerFactory>g__CreateController|0(ControllerContext controllerContext)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextExceptionFilterAsync>g__Awaited|26_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
System.Reflection.ParameterInfo[]

SqlSugar版本：Version=3.4.7.0

数据库连接字符串：server=xxxx;Port=xxxx;Database=xxxx;Uid=xxxx;Pwd=xxxx;AllowLoadLocalInfile=true;SslMode=none;AllowPublicKeyRetrieval=True;

SqlSugar配置：

            public static void SqlSugarConfigure(this IServiceCollection services)
        {
            // 获取选项
            var dbOptions = App.GetOptions<ConnectionStringsOptions>();

            dbOptions.ConnectionConfigs.ForEach(SetDbConfig);

            List<ConnectionConfig> connectConfigList = new List<ConnectionConfig>();

            var conns = dbOptions.ConnectionConfigs.Select(s => new ConnectionConfig
            {
                AopEvents = s.AopEvents,
                ConfigId = s.ConfigId,
                ConnectionString = s.ConnectionString,
                DbLinkName = s.DbLinkName,
                DbType = s.DbType,
                IndexSuffix = s.IndexSuffix,
                IsAutoCloseConnection = s.IsAutoCloseConnection,
                LanguageType = s.LanguageType,
                MoreSettings = s.MoreSettings,
                SlaveConnectionConfigs = s.SlaveConnectionConfigs,
                SqlMiddle = s.SqlMiddle
            }).ToList();

            SqlSugarScope sqlSugar = new(conns, db =>
            {
                dbOptions.ConnectionConfigs.ForEach(config =>
                {
                    var dbProvider = db.GetConnectionScope(config.ConfigId);
                    SetDbAop(dbProvider);
                });
            });
            services.AddSingleton<ISqlSugarClient>(sqlSugar); // 单例注册
            services.AddScoped(typeof(ISqlSugarRepository<>), typeof(SqlSugarRepository<>)); // 仓储注册
            services.AddUnitOfWork<SqlSugarUnitOfWork>(); // 事务与工作单元注册

        }
        
                /// <summary>
        /// 配置连接属性.
        /// </summary>
        /// <param name="config"></param>
        private static void SetDbConfig(DbConnectionConfig config)
        {
            config.ConnectionString = string.Format(config.DefaultConnection, config.DBName);
            config.ConfigureExternalServices = new ConfigureExternalServices
            {
                EntityService = (type, column) => // 处理列
                {
                    if (column.IsPrimarykey == false && new NullabilityInfoContext().Create(type).WriteState is NullabilityState.Nullable)
                        column.IsNullable = true;

                    if (config.DbType == SqlSugar.DbType.Oracle)
                    {
                        if (type.PropertyType == typeof(long) || type.PropertyType == typeof(long?))
                            column.DataType = "number(18)";
                        if (type.PropertyType == typeof(bool) || type.PropertyType == typeof(bool?))
                            column.DataType = "number(1)";
                    }
                },
            };
            config.IsAutoCloseConnection = true;
            config.MoreSettings = new ConnMoreSettings
            {
                IsAutoRemoveDataCache = true,
                SqlServerCodeFirstNvarchar = true // 采用Nvarchar
            };
        }
        
                /// <summary>
        /// 配置Aop.
        /// </summary>
        /// <param name="db"></param>
        public static void SetDbAop(SqlSugarScopeProvider db)
        {
            var config = db.CurrentConnectionConfig;

            // 设置超时时间
            db.Ado.CommandTimeOut = 30;

            // 打印SQL语句
            db.Aop.OnLogExecuting = (sql, pars) =>
            {
                var originColor = Console.ForegroundColor;
                if (sql.StartsWith("SELECT", StringComparison.OrdinalIgnoreCase))
                    Console.ForegroundColor = ConsoleColor.Green;
                if (sql.StartsWith("UPDATE", StringComparison.OrdinalIgnoreCase) || sql.StartsWith("INSERT", StringComparison.OrdinalIgnoreCase))
                    Console.ForegroundColor = ConsoleColor.Yellow;
                if (sql.StartsWith("DELETE", StringComparison.OrdinalIgnoreCase))
                    Console.ForegroundColor = ConsoleColor.Red;
                Console.WriteLine("【" + DateTime.Now + "——执行SQL】\r\n" + UtilMethods.GetSqlString(config.DbType, sql, pars) + "\r\n");
                Console.ForegroundColor = originColor;
                App.PrintToMiniProfiler("SqlSugar", "Info", sql + "\r\n" + db.Utilities.SerializeObject(pars.ToDictionary(it => it.ParameterName, it => it.Value)));
            };
            db.Aop.OnError = ex =>
            {
                if (ex.Parametres == null) return;
                var originColor = Console.ForegroundColor;
                Console.ForegroundColor = ConsoleColor.DarkRed;
                var pars = db.Utilities.SerializeObject(((SugarParameter[])ex.Parametres).ToDictionary(it => it.ParameterName, it => it.Value));
                Console.WriteLine("【" + DateTime.Now + "——错误SQL】\r\n" + UtilMethods.GetSqlString(config.DbType, ex.Sql, (SugarParameter[])ex.Parametres) + "\r\n");
                Console.ForegroundColor = originColor;
                App.PrintToMiniProfiler("SqlSugar", "Error", $"{ex.Message}{Environment.NewLine}{ex.Sql}{pars}{Environment.NewLine}");
            };

            //配置 差异日志功能 功能，记录差异化日志，需要在SqlSugar语句末尾加上 .EnableDiffLogEvent() 方法
            db.Aop.OnDiffLogEvent = it =>
            {
                string requestMethod = "其他";
                switch (it.DiffType)
                {
                    case DiffType.delete:
                        requestMethod = "删除";
                        break;
                    case DiffType.insert:
                        requestMethod = "新增";
                        break;
                    case DiffType.update:
                        requestMethod = "修改";
                        break;
                }

                // 获取请求上下文中的信息（需要在请求中传递）
                var httpContextAccessor = App.HttpContext;
                var context = httpContextAccessor.Request;
                if (context == null) return;
                UserAgent userAgent = new UserAgent(App.HttpContext);
                var apiPath = context.Path;
                //获取修改前修改后的数据
                //记录日志
                var sysLog = new SysLogEntity();
                sysLog.Creator();
                sysLog.UserId = App.User?.FindFirst(ClaimConst.CLAINMUSERID)?.Value ?? "";
                sysLog.UserName = App.User?.FindFirst(ClaimConst.CLAINMREALNAME)?.Value ?? "";
                sysLog.Type = 3;
                sysLog.Level = 1;
                sysLog.IPAddress = NetHelper.Ip;
                sysLog.RequestURL = apiPath;
                sysLog.RequestMethod = requestMethod;
                sysLog.ModuleName = it.BusinessData?.ToString() ?? "";
                sysLog.RequestDuration = (int)(db.Ado.SqlExecutionTime.TotalSeconds * 1000);
                //sysLog.PlatForm = string.Format("{0}-{1}", userAgent.OS.ToString(), userAgent.RawValue);
                //sysLog.ObjectId = item;
                //sysLog.Json = $"审核人【{_userManager.RealName}】,审核时间【{DateTime.Now}】,";
                //_repository.AsSugarClient().Insertable(sysLog).ExecuteCommand();
                sysLog.Json = getDiff(it.BeforeData, it.AfterData).diffData ?? "";//修改的数据
                db.Insertable<SysLogEntity>(sysLog).ExecuteCommand();//保存数据,不要添加.EnableDiffLogEvent()方法
            };

            // 配置实体假删除过滤器
            db.QueryFilter.AddTableFilter<ISoftDeleteFilter>(it => SqlFunc.IsNull(it.DeleteMark, 0) == 0);
        }