Seelog is a powerful and easy-to-learn logging framework that provides functionality for flexible dispatching, filtering, and formatting log messages. It is natively written in the Go programming language.

安装：

go get -u github.com/cihub/seelog

例子：

package main</pre>
<pre>import log "github.com/cihub/seelog"</pre>
<pre>func main() {
   defer log.Flush()
   log.Info("Hello from Seelog!")
}

配置文件：

logger.xml

<seelog>
    <outputs formatid="main">
        <console />
        <filter levels="error" formatid="err">
            <file path="/path/to/log.log" />
        </filter>
    </outputs>
    <formats>
        <format id="main" format="%Date(2006 Jan 02/3:04:05 MST) [%Level] %Msg%n"/>
        <format id="format2" format="%File %FullPath %RelFile %Msg%n"/>
    </formats>
</seelog>

Custome receivers

参考：https://github.com/cihub/seelog/wiki/Custom-receivers
采用seelog.LoggerFromParamConfigAs…，载入xml配置文件以及CfgParseParams.CustomReceiverProducers.
首先定义基本的CustomReceiver类型：

type CustomReceiver struct {
    context SomeContext
}
<pre>func (cr *CustomReceiver) ReceiveMessage(message string, level log.LogLevel, context log.LogContextInterface) error {
    ctxLogger.Log(message, cr.context)
    return nil
}
func (cr *CustomReceiver) AfterParse(initArgs log.CustomReceiverInitArgs) error {
    return nil
}
func (cr *CustomReceiver) Flush() {

}
func (cr *CustomReceiver) Close() error {
    return nil
}

func testLogWithContext(c SomeContext) {
    parserParams := &log.CfgParseParams{
         CustomReceiverProducers: map[string]log.CustomReceiverProducer{
            "myreceiver": func(log.CustomReceiverInitArgs) (log.CustomReceiver, error) {
                return &CustomReceiver{c}, nil
             },
         },
     }
     logger, err := log.LoggerFromParamConfigAsfile(cfgfile, parserParams)
     if err != nil {
          panic(err)
     }
     defer logger.Flush()
     err = log.ReplaceLogger(logger)
     if err != nil {
         panic(err)
     }
     log.Debug("Test1")
     log.Info("Test2")
}