为每个单独的线程记录到单独的日志文件

Question

我有一个服务应用程序，它在启动时读取一个 XML 文件并为 XML 文件中的每个条目启动一个线程。每个线程创建一个工作者类的实例，该实例需要记录器将任何输出记录到线程特定的日志文件中。

在服务 app.config 中，我将 log4net 配置设置设置为使用 XML 附加程序，并将文件指定为 PatternString，如下所示：

<appender name="XmlAppender" type="log4net.Appender.FileAppender">
  <file type="log4net.Util.PatternString" value="D:\Temp\Logs\%property{LogName}.log" />
  <immediateFlush value="true"/>
  <appendToFile value="true" />
  <layout type="log4net.Layout.SimpleLayout" />
</appender>

在创建的每个工作类实例的线程锁定方法中，我使用log4net.LogManager.GetLogger("MyLogger") 方法获取记录器，然后使用ThreadContext.Properties["LogName"] = "Log name prefix" 设置当前线程PatternStrings LogName 属性。

所有文件都已创建，但当记录器被调用时，它只会将所有消息记录到一个看似随机的文件中。

我已经搜索了很长一段时间试图找到解决方案或我做错的一些答案，但我没有运气。

有人知道为什么会这样吗？

Answer 1

我想我已经解决了这个问题。步骤如下：

• 在每个线程上创建一个单独的ILoggerRepository 对象（在本例中为loggerRepository）。
• 为日志文件名设置 ThreadContexts 属性。
• 使用 XmlConfiguratior 配置存储库。
• 使用 LogManager 为该线程使用命名的 LoggerRepository 获取命名的记录器（在 XML 配置文件中）。

作为回报，我得到一个新配置的记录器，指向该线程的相应文件。

XML 配置与最初的配置相同，为了完整起见，此处显示：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>    
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
  </configSections>
  <log4net>
    <logger name="ProductionLogger">
      <appender-ref ref="XmlAppender"/>      
      <level value="ALL"/>
    </logger>
    <appender name="XmlAppender" type="log4net.Appender.FileAppender">
      <file type="log4net.Util.PatternString" value="D:\Temp\Logs\%property{LogName}.log" />
      <immediateFlush value="true"/>
      <appendToFile value="true" />
      <layout type="log4net.Layout.SimpleLayout" />
    </appender>
  </log4net>
</configuration>

创建记录器的代码如下。每次运行此代码时，它都会在自己的线程中运行。

ILoggerRepository loggerRepository = LogManager.CreateRepository(logFileName + "Repository");
ThreadContext.Properties["LogName"] = logFileName;
log4net.Config.XmlConfigurator.Configure(loggerRepository);
ILog logger = LogManager.GetLogger(logFileName + "Repository", "ProductionLogger");

到目前为止，这似乎没有问题。目前我将继续使用此解决方案，但如果我发现其他任何内容，我将更新此帖子。

Answer 2

亚当的回答对我来说效果很好，但我想补充一个。如果您的 logFileName 有可能在您的应用程序中被重用，您需要检查以确保存储库不存在。

string repoName = String.Format("{0}Repository", logFileName);

// Check for existing repository
ILoggerRepository[] allRepos = LogManager.GetAllRepositories();
ILoggerRepository repo = allRepos.Where(x => x.Name == repoName).FirstOrDefault();

// If repository does not exist, create one, set the logfile name, and configure it
if (repo == null)
{
    repo = LogManager.CreateRepository(repoName);
    ThreadContext.Properties[KEY_LOG_FILE] = logFileName;
    log4net.Config.XmlConfigurator.Configure(repo);
}

// Set logger
ILog logger = LogManager.GetLogger(repoName, logName);

Answer 3

@Adam 的解决方案帮助了我。对于后代，这里有一个简单的代码，它创建了 5 个任务（使用线程池中的线程），其中在每个任务中，每个线程写入一个单独的日志文件（然后休眠 1 秒），五次。

.NET 框架 4.7.2
.NET 控制台应用程序

AssemblyInfo.cs

using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

// General Information about an assembly is controlled through the following
// set of attributes. Change these attribute values to modify the information
// associated with an assembly.
[assembly: AssemblyTitle("LogfilePerThread")]
[assembly: AssemblyDescription("")]
[assembly: AssemblyConfiguration("")]
[assembly: AssemblyCompany("Microsoft")]
[assembly: AssemblyProduct("LogfilePerThread")]
[assembly: AssemblyCopyright("Copyright © Microsoft 2020")]
[assembly: AssemblyTrademark("")]
[assembly: AssemblyCulture("")]

// Setting ComVisible to false makes the types in this assembly not visible
// to COM components.  If you need to access a type in this assembly from
// COM, set the ComVisible attribute to true on that type.
[assembly: ComVisible(false)]

// The following GUID is for the ID of the typelib if this project is exposed to COM
[assembly: Guid("d3ec8b29-e701-424e-80d4-473e9fbb5572")]

// Version information for an assembly consists of the following four values:
//
//      Major Version
//      Minor Version
//      Build Number
//      Revision
//
// You can specify all the values or you can default the Build and Revision Numbers
// by using the '*' as shown below:
// [assembly: AssemblyVersion("1.0.*")]
[assembly: AssemblyVersion("1.0.0.0")]
[assembly: AssemblyFileVersion("1.0.0.0")]

Program.cs

using System;
using System.Threading;
using System.Threading.Tasks;
using log4net;
using log4net.Repository;

namespace LogfilePerThread
{
    class Program
    {
        static void Main(string[] args)
        {
            int nWorkers = 5; // 5 workers, 5 log files
            Task[] Workers = new Task[nWorkers];
            for (int i = 0; i < nWorkers; i++)
            {
                int i1 = i;
                Workers[i] = new Task(() => Work(i1));
                Workers[i].Start();
            }

            Task.WaitAll(Workers);
            Console.WriteLine("Main executed.");
        }

        public static void Work(int workerID)
        {
            // Make sure the directory where logfiles are written exists
            string logfileName = $"Worker{workerID}_TaskLog"; // Logfile extension & path specified in App.config
            ILoggerRepository repository = LogManager.CreateRepository($"{logfileName}Repository");
            ThreadContext.Properties["WorkerLoggerProperty"] = logfileName;
            log4net.Config.XmlConfigurator.Configure(repository);
            ILog log = LogManager.GetLogger($"{logfileName}Repository", "WorkerLogger"); // Use this logger object in thread

            // Do work: Log & Sleep
            for (int i = 0; i < 5; i++)
            {
                log.Info($"Logging from WorkerID={workerID} - Msg {i}");
                Thread.Sleep(1000);
            }
        }
    }
}

App.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
  </configSections>

  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.7.2" />
  </startup>

  <log4net>

    <logger name="WorkerLogger">
      <level value="DEBUG" />
      <appender-ref ref="RollingFile" />
    </logger>

    <appender name="RollingFile" type="log4net.Appender.RollingFileAppender">
      <file type="log4net.Util.PatternString" value="C:\logs\%property{WorkerLoggerProperty}.log" />
      <appendToFile value="true" />
      <immediateFlush value="true"/>
      <layout type="log4net.Layout.PatternLayout">
        <conversionPattern value="%date [%5level, %thread] %message%newline" />
      </layout>
    </appender>

  </log4net>

</configuration>

C:\logs\Worker0_TaskLog.log

2020-01-14 21:59:46,696 [ INFO, 3] Logging from WorkerID=0 - Msg 0
2020-01-14 21:59:47,714 [ INFO, 3] Logging from WorkerID=0 - Msg 1
2020-01-14 21:59:48,714 [ INFO, 3] Logging from WorkerID=0 - Msg 2
2020-01-14 21:59:49,714 [ INFO, 3] Logging from WorkerID=0 - Msg 3
2020-01-14 21:59:50,714 [ INFO, 3] Logging from WorkerID=0 - Msg 4

C:\logs\Worker1_TaskLog.log

2020-01-14 21:59:46,696 [ INFO, 4] Logging from WorkerID=1 - Msg 0
2020-01-14 21:59:47,714 [ INFO, 4] Logging from WorkerID=1 - Msg 1
2020-01-14 21:59:48,714 [ INFO, 4] Logging from WorkerID=1 - Msg 2
2020-01-14 21:59:49,714 [ INFO, 4] Logging from WorkerID=1 - Msg 3
2020-01-14 21:59:50,714 [ INFO, 4] Logging from WorkerID=1 - Msg 4

C:\logs\Worker2_TaskLog.log

2020-01-14 21:59:46,697 [ INFO, 5] Logging from WorkerID=2 - Msg 0
2020-01-14 21:59:47,713 [ INFO, 5] Logging from WorkerID=2 - Msg 1
2020-01-14 21:59:48,713 [ INFO, 5] Logging from WorkerID=2 - Msg 2
2020-01-14 21:59:49,713 [ INFO, 5] Logging from WorkerID=2 - Msg 3
2020-01-14 21:59:50,713 [ INFO, 5] Logging from WorkerID=2 - Msg 4

C:\logs\Worker3_TaskLog.log

2020-01-14 21:59:46,696 [ INFO, 6] Logging from WorkerID=3 - Msg 0
2020-01-14 21:59:47,714 [ INFO, 6] Logging from WorkerID=3 - Msg 1
2020-01-14 21:59:48,714 [ INFO, 6] Logging from WorkerID=3 - Msg 2
2020-01-14 21:59:49,714 [ INFO, 6] Logging from WorkerID=3 - Msg 3
2020-01-14 21:59:50,714 [ INFO, 6] Logging from WorkerID=3 - Msg 4

C:\logs\Worker4_TaskLog.log

2020-01-14 21:59:47,580 [ INFO, 7] Logging from WorkerID=4 - Msg 0
2020-01-14 21:59:48,580 [ INFO, 7] Logging from WorkerID=4 - Msg 1
2020-01-14 21:59:49,580 [ INFO, 7] Logging from WorkerID=4 - Msg 2
2020-01-14 21:59:50,580 [ INFO, 7] Logging from WorkerID=4 - Msg 3
2020-01-14 21:59:51,580 [ INFO, 7] Logging from WorkerID=4 - Msg 4