使数据库关闭后log4net重新连接到数据库

Question

我使用Log4Net Windows Service将日志保存在数据库中。 我收到以下错误：

log4net:ERROR [CustomAdoNetAppender] ErrorCode: GenericFailure. Failed in DoAppend 
System.Data.SqlClient.SqlException (0x80131904): Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding. ---> System.ComponentModel.Win32Exception (0x80004005): The wait operation timed out 
    at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction) 
    at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) 
    at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error) 
    at System.Data.SqlClient.TdsParserStateObject.ReadSniSyncOverAsync() 
    at System.Data.SqlClient.TdsParserStateObject.TryReadNetworkPacket() 
    at System.Data.SqlClient.TdsParserStateObject.TryPrepareBuffer() 
    at System.Data.SqlClient.TdsParserStateObject.TryReadByte(Byte& value) 
    at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) 
    at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) 
    at System.Data.SqlClient.TdsParser.TdsExecuteTransactionManagerRequest(Byte[] buffer, TransactionManagerRequestType request, String transactionName, TransactionManagerIsolationLevel isoLevel, Int32 timeout, SqlInternalTransaction transaction, TdsParserStateObject stateObj, Boolean isDelegateControlRequest) 
    at System.Data.SqlClient.SqlInternalConnectionTds.ExecuteTransactionYukon(TransactionRequest transactionRequest, String transactionName, IsolationLevel iso, SqlInternalTransaction internalTransaction, Boolean isDelegateControlRequest) 
    at System.Data.SqlClient.SqlInternalConnectionTds.ExecuteTransaction(TransactionRequest transactionRequest, String name, IsolationLevel iso, SqlInternalTransaction internalTransaction, Boolean isDelegateControlRequest) 
    at System.Data.SqlClient.SqlInternalConnection.BeginSqlTransaction(IsolationLevel iso, String transactionName, Boolean shouldReconnect) 
    at System.Data.SqlClient.SqlConnection.BeginTransaction(IsolationLevel iso, String transactionName) 
    at System.Data.SqlClient.SqlConnection.BeginDbTransaction(IsolationLevel isolationLevel) 
    at System.Data.Common.DbConnection.System.Data.IDbConnection.BeginTransaction() 
    at log4net.Appender.AdoNetAppender.SendBuffer(LoggingEvent[] events) 
    at log4net.Appender.BufferingAppenderSkeleton.Append(LoggingEvent loggingEvent) 
    at log4net.Appender.AppenderSkeleton.DoAppend(LoggingEvent loggingEvent) 
ClientConnectionId:a0b7de5e-2689-407b-b0da-5ebc733c0986 
log4net: Attempting to reconnect to database. Current Connection State: Closed 
log4net: Attempting to reconnect to database. Current Connection State: (null) 
log4net: Attempting to reconnect to database. Current Connection State: (null) 
log4net: Attempting to reconnect to database. Current Connection State: (null) 
log4net: Attempting to reconnect to database. Current Connection State: (null) 

我在服务窗口配置Lo4Net是：

<log4net> 
    <appender name="AdoNetAppender" type="App.Uteis.CustomAdoNetAppender"> 
     <bufferSize value="1" /> 
     <reconnectonerror value="true" /> 
     <connectionType value="System.Data.SqlClient.SqlConnection, System.Data, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" /> 
     <commandText value="INSERT INTO Log_Aplicacao ([Dt_Log],[Ds_Thread],[Ds_Nivel],[Ds_Servidor],[Ds_Aplicacao],[Ds_Login],[Ds_Log],[Ds_Mensagem],[Ds_Erro]) VALUES (@log_date, @thread, @log_level, @host_name,'AppMaster', @user_name, @logger, @message, @exception)" /> 
     <parameter> 
     <parameterName value="@log_date" /> 
     <dbType value="DateTime" /> 
     <layout type="log4net.Layout.RawTimeStampLayout" /> 
     </parameter> 
     <parameter> 
     <parameterName value="@thread" /> 
     <dbType value="String" /> 
     <size value="255" /> 
     <layout type="log4net.Layout.PatternLayout"> 
      <conversionPattern value="%thread" /> 
     </layout> 
     </parameter> 
     <parameter> 
     <parameterName value="@log_level" /> 
     <dbType value="String" /> 
     <size value="50" /> 
     <layout type="log4net.Layout.PatternLayout"> 
      <conversionPattern value="%level" /> 
     </layout> 
     </parameter> 
     <parameter> 
     <parameterName value="@host_name" /> 
     <dbType value="String" /> 
     <size value="200" /> 
     <layout type="log4net.Layout.PatternLayout"> 
      <conversionPattern value="%property{log4net:HostName}" /> 
     </layout> 
     </parameter> 
     <parameter> 
     <parameterName value="@user_name" /> 
     <dbType value="String" /> 
     <size value="150" /> 
     <layout type="log4net.Layout.PatternLayout"> 
      <conversionPattern value="%username" /> 
     </layout> 
     </parameter> 
     <parameter> 
     <parameterName value="@logger" /> 
     <dbType value="String" /> 
     <size value="2000" /> 
     <layout type="log4net.Layout.PatternLayout"> 
      <conversionPattern value="%logger" /> 
     </layout> 
     </parameter> 
     <parameter> 
     <parameterName value="@message" /> 
     <dbType value="String" /> 
     <size value="8000" /> 
     <layout type="log4net.Layout.PatternLayout"> 
      <conversionPattern value="%message" /> 
     </layout> 
     </parameter> 
     <parameter> 
     <parameterName value="@exception" /> 
     <dbType value="String" /> 
     <size value="8000" /> 
     <layout type="log4net.Layout.ExceptionLayout" /> 
     </parameter> 
    </appender> 
    <root> 
     <level value="ALL" /> 
     <appender-ref ref="AdoNetAppender" /> 
    </root> 
    </log4net> 

我CustomAdoNetAppender类的配置是：只有

namespace AprovadorCartao.Uteis 
{ 
    public class CustomAdoNetAppender : AdoNetAppender 
    { 
     public static RegistryKey _configRegistry = Registry.LocalMachine.OpenSubKey("Software\\Conexao"); 

     public override void ActivateOptions() 
     { 
      PopulateConnectionString(); 
      base.ActivateOptions(); 
     } 

     private void PopulateConnectionString() 
     { 
      ConnectionString = ConnectionString; 
     } 

     public new string ConnectionString 
     { 
      get { return base.ConnectionString; } 
      set 
      { 
       base.ConnectionString = (string)_configRegistry.GetValue("Conexao") + ";Connect Timeout=1;"; 
      } 
     } 
    } 
} 

log4net的在重新启动服务后恢复正常（保存在数据库中）。

每次我的数据库出现错误时，Log4Net都会将数据保存到数据库中。 Log4Net是否有配置可以自动登录Windows服务？

Answer 1

由于您已经设置了reconnectOnError = true并且您正在使用适当的低连接超时时间，因此您处于正确的轨道上 - 问题在这里我认为您不是通过设置正确覆盖连接字符串，而应该覆盖ResolveConnectionString()替代超时值：

protected override string ResolveConnectionString(out string connectionStringContext) 
{ 
    var connectionString = base.ResolveConnectionString(out connectionStringContext); 

    if (string.IsNullOrEmpty(connectionString) || ReconnectOnError == false) 
    { 
     return connectionString; 
    } 

    var builder = new SqlConnectionStringBuilder(connectionString) 
    { 
     ConnectTimeout = 1; // Timeout value 
    }; 

    return builder.ConnectionString; 
}