背景

1. 基于之前基于Log4Net本地日志服务简单实现 实现本地日志服务，但是随着项目开发演进，本地日志服务满足不了需求，譬如在预发布环境或者生产环境，不可能让开发人员登录查看本地日志文件分析。
2. Kafka+ELK日志服务套件，可以在线日志服务可以解决上述问题，并且提供丰富报表分析等等；
3. 具体源码：MasterChief
4. Nuget：Install-Package MasterChief.DotNet.Core.KafkaLog
5. 欢迎Star，欢迎Issues；

源码

1. 基于Log4Net来实现与kafka通讯Appender

    public class KafkaAppender : AppenderSkeleton
    {
        #region Fields
   
        /// <summary>
        ///     Kafka 生产者
        /// </summary>
        private Producer _kafkaProducer;
   
        #endregion Fields
   
        #region Properties
   
        /// <summary>
        ///     Brokers
        /// </summary>
        public string Brokers { get; set; }
   
        /// <summary>
        ///     Topic
        /// </summary>
        public string Topic { get; set; }
   
        #endregion Properties
   
        #region Methods
   
        /// <summary>
        ///     Initialize the appender based on the options set
        /// </summary>
        /// <remarks>
        ///     <para>
        ///         This is part of the <see cref="T:log4net.Core.IOptionHandler" /> delayed object
        ///         activation scheme. The <see cref="M:log4net.Appender.AppenderSkeleton.ActivateOptions" /> method must
        ///         be called on this object after the configuration properties have
        ///         been set. Until <see cref="M:log4net.Appender.AppenderSkeleton.ActivateOptions" /> is called this
        ///         object is in an undefined state and must not be used.
        ///     </para>
        ///     <para>
        ///         If any of the configuration properties are modified then
        ///         <see cref="M:log4net.Appender.AppenderSkeleton.ActivateOptions" /> must be called again.
        ///     </para>
        /// </remarks>
        public override void ActivateOptions()
        {
            base.ActivateOptions();
            InitKafkaProducer();
        }
   
        /// <summary>
        ///     Subclasses of <see cref="T:log4net.Appender.AppenderSkeleton" /> should implement this method
        ///     to perform actual logging.
        /// </summary>
        /// <param name="loggingEvent">The event to append.</param>
        /// <remarks>
        ///     <para>
        ///         A subclass must implement this method to perform
        ///         logging of the <paramref name="loggingEvent" />.
        ///     </para>
        ///     <para>
        ///         This method will be called by <see cref="M:DoAppend(LoggingEvent)" />
        ///         if all the conditions listed for that method are met.
        ///     </para>
        ///     <para>
        ///         To restrict the logging of events in the appender
        ///         override the <see cref="M:PreAppendCheck()" /> method.
        ///     </para>
        /// </remarks>
        protected override void Append(LoggingEvent loggingEvent)
        {
            try
            {
                var message = GetLogMessage(loggingEvent);
                var topic = GetTopic(loggingEvent);
   
                _ = _kafkaProducer.SendMessageAsync(topic, new[] {new Message(message)});
            }
            catch (Exception ex)
            {
                ErrorHandler.Error("KafkaProducer SendMessageAsync", ex);
            }
        }
   
        /// <summary>
        ///     Raises the Close event.
        /// </summary>
        /// <remarks>
        ///     <para>
        ///         Releases any resources allocated within the appender such as file handles,
        ///         network connections, etc.
        ///     </para>
        ///     <para>
        ///         It is a programming error to append to a closed appender.
        ///     </para>
        /// </remarks>
        protected override void OnClose()
        {
            base.OnClose();
            StopKafkaProducer();
        }
   
        private string GetLogMessage(LoggingEvent loggingEvent)
        {
            var builder = new StringBuilder();
            us