asp.net core 集成 log4net 日志框架

Intro

在 asp.net core 中有些日志我们可能想输出到数据库或文件或elasticsearch等，如果不自己去实现一个 LoggerProvider 的话就需要借助第三方日志框架实现了，而一些第三方框架的实现大多比较完善和成熟，不失为一个好办法。

自己写了一个 log4net 的扩展 WeihanLi.Common.Logging.Log4Net，提供了在 .net core 中使用 log4net 的扩展

安装 nuget 包

通过 nuget 安装 WeihanLi.Common.Logging.Log4Net

使用

基本使用

ILoggerFactory loggerFactory = new LoggerFactory();loggerFactory.AddLog4Net(); // loggerFactory.AddLog4Net(log4netConfigFilePath);

你可以在 asp.net core 应用里你的 Startup 文件中使用下面代码进行配置

// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory) ???????{ ???????????loggerFactory.AddLog4Net(); // loggerFactory.AddLog4Net(log4netConfigFilePath); ???????????// ... ???????}

默认使用当前目录下的 log4net.config 文件作为 log4net 的配置文件，如果不是需要自己设置 log4net 配置文件的路径。

log4net 配置参考 示例配置

源码解析

项目源码

Log4NetLoggerProvider

• 实现记录日志的 ILogger

 ???internal class Log4NetLogger : ILogger ???{ ???????private readonly ILog _logger; ???????public Log4NetLogger(string name) => _logger = LogManager.GetLogger(ApplicationHelper.ApplicationName, name); ???????public IDisposable BeginScope<TState>(TState state) => NullScope.Instance; ???????public bool IsEnabled(LogLevel logLevel) ???????{ ???????????switch (logLevel) ???????????{ ???????????????case LogLevel.Critical: ???????????????????return _logger.IsFatalEnabled; ???????????????case LogLevel.Debug: ???????????????case LogLevel.Trace: ???????????????????return _logger.IsDebugEnabled; ???????????????case LogLevel.Error: ???????????????????return _logger.IsErrorEnabled; ???????????????case LogLevel.Information: ???????????????????return _logger.IsInfoEnabled; ???????????????case LogLevel.Warning: ???????????????????return _logger.IsWarnEnabled; ???????????????case LogLevel.None: ???????????????????return false; ???????????????default: ???????????????????throw new ArgumentOutOfRangeException(nameof(logLevel)); ???????????} ???????} ???????public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, ???????????Exception exception, Func<TState, Exception, string> formatter) ???????{ ???????????if (!IsEnabled(logLevel)) ???????????{ ???????????????return; ???????????} ???????????if (formatter == null) ???????????{ ???????????????throw new ArgumentNullException(nameof(formatter)); ???????????} ???????????var message = formatter(state, exception); ???????????if (!(string.IsNullOrEmpty(message) && exception == null)) ???????????{ ???????????????switch (logLevel) ???????????????{ ???????????????????case LogLevel.Critical: ???????????????????????_logger.Fatal(message, exception); ???????????????????????break; ???????????????????case LogLevel.Debug: ???????????????????case LogLevel.Trace: ???????????????????????_logger.Debug(message, exception); ???????????????????????break; ???????????????????case LogLevel.Error: ???????????????????????_logger.Error(message, exception); ???????????????????????break; ???????????????????case LogLevel.Information: ???????????????????????_logger.Info(message, exception); ???????????????????????break; ???????????????????case LogLevel.Warning: ???????????????????????_logger.Warn(message, exception); ???????????????????????break; ???????????????????default: ???????????????????????_logger.Warn($"Encountered unknown log level {logLevel}, writing out as Info."); ???????????????????????_logger.Info(message, exception); ???????????????????????break; ???????????????} ???????????} ???????} ???}

• 实现提供 logger 的 ILoggerProvider

 ???[ProviderAlias("log4net")] ???internal class Log4NetLoggerProvider : ILoggerProvider ???{ ???????private readonly ConcurrentDictionary<string, Log4NetLogger> _loggers = ???????????new ConcurrentDictionary<string, Log4NetLogger>(StringComparer.Ordinal); ???????public Log4NetLoggerProvider(string confFilePath) ???????{ ???????????if (null == LogManager.GetAllRepositories()?.FirstOrDefault(_ => _.Name == ApplicationHelper.ApplicationName)) ???????????{ ???????????????XmlConfigurator.ConfigureAndWatch(LogManager.CreateRepository(ApplicationHelper.ApplicationName), new FileInfo(confFilePath)); ???????????} ???????} ???????public void Dispose() => _loggers.Clear(); ???????public ILogger CreateLogger(string categoryName) => _loggers.GetOrAdd(categoryName, loggerName => new Log4NetLogger(loggerName)); ???}

• 添加 ILoggerFactory 扩展

 ???public static class Log4NetLoggerFactoryExtensions ???{ ???????public static ILoggerFactory AddLog4Net(this ILoggerFactory factory) ???????{ ???????????factory.AddProvider(new Log4NetLoggerProvider(ApplicationHelper.MapPath("log4net.config"))); ???????????return factory; ???????} ???????public static ILoggerFactory AddLog4Net(this ILoggerFactory factory, string configFile) ???????{ ???????????factory.AddProvider(new Log4NetLoggerProvider(configFile)); ???????????return factory; ???????} ???}

Memo

如果有什么问题或建议，欢迎指出

asp.net core 集成 log4net 日志框架

原文地址：https://www.cnblogs.com/lonelyxmas/p/10474509.html