log4net 自定义Appender

最近有个需求，使用log4net来记录日志，然后将数据保存到服务器端。一开始打算写一个windows service，定期上传日志。

后来又因为一些场景下不适应，因此直接改为保存内存中，到一定阀值之后将数据post到服务器。

考虑用log4net的MemoryAppender，但是没办法控制这个阀值，同时还需要另外配置服务器接受数据地址。

因此也不适用，还好log4net支持自定义Appender，于是，参考MemoryAppender，自定义一个，问题解决。

下面是Appender代码。

 /// <summary>
    /// Customize Appender, save the Log in the memory
    /// when it the event queue reach maximum queue size
    /// the queue will post to sever.
    /// </summary>
    public class MyMemAppender : AppenderSkeleton
    {
        #region public properties
        public string RemoteAddress { get; set; }
        public int QueueSize { get; set; }
        #endregion

        #region Public Instance Constructors
        public MyMemAppender()
            : base()
        {
            eventQueue = new ArrayList();
        }        
        #endregion

        #region private fields
        private ArrayList eventQueue;
        #endregion

        #region Override implementation of AppenderSkeleton
        protected override void Append(log4net.Core.LoggingEvent loggingEvent)
        {
            lock (eventQueue.SyncRoot)
            {
                eventQueue.Add(loggingEvent);
                if (eventQueue.Count >= QueueSize)
                {
                    this.Clear();
                }
            }
        }
        #endregion

        #region Public Instance Methods

        /// <summary>
        /// Clear the list of events
        /// </summary>
        /// <remarks>
        /// Clear the list of events
        /// </remarks>
        virtual public void Clear()
        {
            lock (eventQueue.SyncRoot)
            {
                SaveToServer();
                eventQueue.Clear();
            }
        }

        /// <summary>
        /// Gets the events that have been logged.
        /// </summary>
        /// <returns>The events that have been logged</returns>
        /// <remarks>
        /// <para>
        /// Gets the events that have been logged.
        /// </para>
        /// </remarks>
        virtual public LoggingEvent[] GetEvents()
        {
            lock (eventQueue.SyncRoot)
            {
                return (LoggingEvent[])eventQueue.ToArray(typeof(LoggingEvent));
            }
        }

        #endregion Public Instance Methods

        #region private methods
        private void SaveToServer()
        {
            lock (eventQueue.SyncRoot)
            {
                List<LogModel> logList = new List<LogModel>();
                foreach (log4net.Core.LoggingEvent evt in eventQueue)
                {
                    try
                    {
                        LogModel m = Newtonsoft.Json.JsonConvert.DeserializeObject<LogModel>(evt.RenderedMessage);
                        logList.Add(m);
                    }
                    catch (Exception ex)
                    {
                        Console.Write(ex.ToString());
                        continue;
                    }
                }
                SaveToServer(logList);
            }
        }

        private void SaveToServer(List<LogModel> logList)
        {
            try
            {
                IsoDateTimeConverter timeConverter = new IsoDateTimeConverter();
                timeConverter.DateTimeFormat = "yyyy'-'MM'-'dd' 'HH':'mm':'ss";
                string str = Newtonsoft.Json.JsonConvert.SerializeObject(logList, Newtonsoft.Json.Formatting.Indented, timeConverter);
                PostStrToServer(str, RemoteAddress);
            }
            catch (Exception ex)
            {
                Console.Write(ex.ToString());
                return;
            }
        }

        private void PostStrToServer(string content, string url)
        {
            using (WebClient client = new WebClient())
            {
                client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
                client.Encoding = System.Text.Encoding.UTF8;
                client.UploadStringAsync(new Uri(url), ("logList=" + content));
            }
        }

        #endregion
    }

配置文件：

<?xml version="1.0" encoding="utf-8" ?>
<log4net debug="true">
<appender name="myMemAppender" type="LogSystem.Common.MyMemAppender">
    <param name="QueueSize" value="10"/>
    <param name="RemoteAddress" value="http://localhost/PostLogData.aspx"/>
</appender>
<root>
   <level value="ALL"/>
   <appender-ref ref="myMemAppender" />
</root>
</log4net>

调用方式：

MyMemAppender logger = new MyMemAppender();
logger.QueueSize = 5;
logger.RemoteAddress = "http://localhost:57427/PostLogData.aspx";
log4net.Config.BasicConfigurator.Configure(logger);
ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

或者

log4net.Config.XmlConfigurator.Configure(new System.IO.FileInfo(configPath));
log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);