logger.go

package main

import (
	"fmt"
	"github.com/sirupsen/logrus"
	"os"
	"runtime"
	"strings"
)

var (
	logger = logrus.New()
	verbose bool
)

func SetLogLevel(level logrus.Level) {
	logger.Level = level
}

func SetLogFormatter(formatter logrus.Formatter) {
	logger.Formatter = formatter
}

// Debug logs a message at level Debug on the standard logger.
func Debug(args ...interface{}) {
	if logger.Level >= logrus.DebugLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Debug(args...)
	}
}

// Debug logs with format message at level Debug on the standard logger.
func Debugf(format string, args ...interface{}) {
	if logger.Level >= logrus.DebugLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Debugf(format, args...)
	}
}

// Info logs a message at level Info on the standard logger.
func Info(args ...interface{}) {
	if logger.Level >= logrus.InfoLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Info(args...)
	}
}

// Info logs with format message at level Info on the standard logger.
func Infof(format string, args ...interface{}) {
	if logger.Level >= logrus.InfoLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Infof(format, args...)
	}
}

// Warn logs a message at level Warn on the standard logger.
func Warn(args ...interface{}) {
	if logger.Level >= logrus.WarnLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Warn(args...)
	}
}

// Warn logs with format message at level Warn on the standard logger.
func Warnf(format string, args ...interface{}) {
	if logger.Level >= logrus.WarnLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Warnf(format, args...)
	}
}

// Error logs a message at level Error on the standard logger.
func Error(args ...interface{}) {
	if logger.Level >= logrus.ErrorLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Error(args...)
	}
}

// Error logs with format message at level Error on the standard logger.
func Errorf(format string, args ...interface{}) {
	if logger.Level >= logrus.ErrorLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Errorf(format, args...)
	}
}

// Fatal logs a message at level Fatal on the standard logger.
func Fatal(args ...interface{}) {
	if logger.Level >= logrus.FatalLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Fatal(args...)
	}
}

// Fatal logs with format message at level Fatal on the standard logger.
func Fatalf(format string, args ...interface{}) {
	if logger.Level >= logrus.FatalLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Fatalf(format, args...)
	}
}

// Panic logs a message at level Panic on the standard logger.
func Panic(args ...interface{}) {
	if logger.Level >= logrus.PanicLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Panic(args...)
	}
}

// Panic logs with format message at level Panic on the standard logger.
func Panicf(format string, args ...interface{}) {
	if logger.Level >= logrus.PanicLevel {
		entry := logger.WithFields(logrus.Fields{})
		if verbose{
			entry.Data["file"] = fileInfo(2)
		}
		entry.Panicf(format, args...)
	}
}

// Display the file and the line number where the command was executed
func fileInfo(skip int) string {
	_, file, line, ok := runtime.Caller(skip)
	if !ok {
		file = "<???>"
		line = 1
	} else {
		slash := strings.LastIndex(file, "/")
		if slash >= 0 {
			file = file[slash+1:]
		}
	}
	return fmt.Sprintf("%s:%d", file, line)
}

// Setup or Initialize the logger
func initLogger() {
	// is it a verbose mode
	logLevel := os.Getenv("LOG_LEVEL")
	if strings.ToLower(logLevel) == "debug" {
		verbose = true
	}

	// Set the formatter option for logrus
	formatter := new(logrus.TextFormatter)
	formatter.TimestampFormat = "2006-01-02 15:04:05"
	formatter.FullTimestamp = true

	// Set the formatter.
	SetLogFormatter(formatter)

	// if log level
	if verbose {
		SetLogLevel(logrus.DebugLevel)
	} else {
		SetLogLevel(logrus.InfoLevel)
	}
}