net_log.go

package loglib

import (
   "time"
   "net"
   "log"
   "logd/tcp_pack"
   "encoding/json"
   "runtime"
   "strings"
   "os"
   "os/exec"
   "path/filepath"
   "sync"
)

type NetLog struct {
    conn *net.TCPConn
    level int
    addr string     //tcp address
    ip string       //self ip
    mutex *sync.Mutex
}

func NewNetLog(addr string, level int) *NetLog {
    conn, _ := getConnection(addr)
    mutex := &sync.Mutex{}
    return &NetLog{conn, level, addr, getIp(), mutex}
}

func getIp() string {
    out, _ := exec.Command("/bin/sh", "-c", `/sbin/ifconfig | awk -F"[: ]+" '/inet addr/{print $4}' | head -n 1`).Output()
    return strings.Trim(string(out), "\n")
}

//获取可执行文件的所在路径
func getBinPath() string {
    d, err := filepath.Abs(filepath.Dir(os.Args[0]))
    if err != nil {
        log.Println("[get bin path] error:", err)
    }
    return d
}

func getConnection(addr string) (*net.TCPConn, error) {
    tcpAddr, err := net.ResolveTCPAddr("tcp4", addr)
    if err != nil {
        _, f, l, _ := runtime.Caller(1)
        f = strings.Replace(f, getBinPath(), "", -1)
        log.Println(f, ":", l, "[GetConnection] resolve tcp address failed", err)
        return nil, err
    }
    conn, err := net.DialTCP("tcp4", nil, tcpAddr)
    if err != nil {
        _, f, l, _ := runtime.Caller(1)
        f = strings.Replace(f, getBinPath(), "", -1)
        log.Println(f, ":", l, "[GetConnection] connect to address:" , addr, "failed!")
    }
    return conn, err
}

func (l *NetLog) logging(level int, msg string) {
    if level >= 0  && level < len(prefixes) {
        l.mutex.Lock()

        if l.conn == nil {
            l.conn, _ = getConnection(l.addr)    //重连一次
        }

        if l.conn != nil {
            m := map[string]string{"time": time.Now().Format("2006/01/02 15:04:05"), "type": prefixes[level], "msg":msg, "ip": l.ip, "port": HeartBeatPort}
            data, err := json.Marshal(m)
            if err != nil {
                log.Println("marshal net log error:", err)
                return
            }
            data = tcp_pack.Pack(data)
            _, err = l.conn.Write(data)
            if err != nil {
                log.Println("send log failed: ", msg, "error:", err)
            }else{
                log.Println("send log :" + msg)
            }
        }else{
            log.Println("send log failed: ", msg, "error: no connection")
        }
        l.mutex.Unlock()
    }

}
//设置日志级别，低于该级别的日志将不输出
func (l *NetLog) SetLevel(level int) bool {
    if level >= 0  && level < len(prefixes) {
        l.level = level
        return true
    }else {
        log.Println("invalid log level")
    }
    return false
    
}

func (l *NetLog) Debug(msg string) {
    if l.level == DEBUG {
       l.logging(DEBUG, msg) 
    }
}

func (l *NetLog) Info(msg string) {
    if l.level <= INFO {
       l.logging(INFO, msg) 
    }
}

func (l *NetLog) Warning(msg string) {
    if l.level <= WARNING {
       l.logging(WARNING, msg) 
    }
}

func (l *NetLog) Error(msg string) {
    if l.level <= ERROR {
       l.logging(ERROR, msg) 
    }
}