最简单的方式实现 Golang的级别日志

log.go

 

package log

import (
    "fmt"
    "io"
    "log"
    "os"
)

const (
    Ldate         = 1 << iota     // the date in the local time zone: 2009/01/23
    Ltime                         // the time in the local time zone: 01:23:23
    Lmicroseconds                 // microsecond resolution: 01:23:23.123123.  assumes Ltime.
    Llongfile                     // full file name and line number: /a/b/c/d.go:23
    Lshortfile                    // final file name element and line number: d.go:23. overrides Llongfile
    LUTC                          // if Ldate or Ltime is set, use UTC rather than the local time zone
    Lmsgprefix                    // move the "prefix" from the beginning of the line to before the message
    LstdFlags     = Ldate | Ltime // initial values for the standard logger
)
const (
    TRACE int = iota
    DEBUG
    INFO
    WARN
    ERROR
    FATAL
)

var l *LevelLogger

type LevelLogger struct {
    level  int
    stdout bool
    logger *log.Logger
}

type logWriter struct {
    Writer io.Writer
}

func newLogWriter(writer io.Writer) *logWriter {
    return &logWriter{writer}
}

func (w *logWriter) Write(data []byte) (int, error) {
    if l.stdout {
        fmt.Print(string(data))
    }
    return w.Writer.Write(data)
}

func init() {
    l = &LevelLogger{
        level:  TRACE,
        logger: log.New(os.Stdout, "", log.LstdFlags|log.Lshortfile),
    }
}
func SetLevel(level int) {
    l.level = level
}
func SetLogger(logger *log.Logger) {
    l.logger = logger
}
func SetFlags(flag int) {
    l.logger.SetFlags(flag)
}
func SetOutFile(filepath string, stdout bool) {
    l.stdout = stdout
    filePtr, err := os.OpenFile(filepath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0666)
    if err != nil {
        log.Panic(err)
    }
    l.logger.SetOutput(newLogWriter(filePtr))
}
func SetPrefix(prefix string) {
    l.logger.SetPrefix(prefix)
}
func SetOutput(w io.Writer) {
    l.logger.SetOutput(w)
}
func output(v ...any) {
    err := l.logger.Output(3, fmt.Sprintln(v...))
    if err != nil {
        fmt.Println(err)
    }
}
func Trace(v ...any) {
    if TRACE >= l.level {
        output(fmt.Sprintf("[PID:%d]", os.Getpid()), "[TRACE]", fmt.Sprint(v...))
    }
}
func Debug(v ...any) {
    if DEBUG >= l.level {
        output(fmt.Sprintf("[PID:%d]", os.Getpid()), "[DEBUG]", fmt.Sprint(v...))
    }
}
func Info(v ...any) {
    if INFO >= l.level {
        output(fmt.Sprintf("[PID:%d]", os.Getpid()), "[INFO]", fmt.Sprint(v...))
    }
}
func Warn(v ...any) {
    if WARN >= l.level {
        output(fmt.Sprintf("[PID:%d]", os.Getpid()), "[WARN]", fmt.Sprint(v...))
    }
}
func Error(v ...any) {
    if ERROR >= l.level {
        output(fmt.Sprintf("[PID:%d]", os.Getpid()), "[ERROR]", fmt.Sprint(v...))
    }
}
func Fatal(v ...any) {
    if FATAL >= l.level {
        output(fmt.Sprintf("[PID:%d]", os.Getpid()), "[FATAL]", fmt.Sprint(v...))
        os.Exit(0)
    }
}
func Println(v ...any) {
    fmt.Println(v...)
}

 

 

main.go

package main

import (
    "awesomeProject1/log"
)

func main() {
    log.SetLevel(log.INFO)
    log.SetOutFile("test.log", true)
    log.Trace("the is Trace")
    log.Debug("the is Debug")
    log.Info("the is Info")
    log.Warn("the is Warn")
    log.Error("the is Error")
    log.Fatal("the is Fatal", 1, 2, 3, 4, 5, 6, 7, 8, 9)
}