golib/logger/level.go

/*
MIT License

Copyright (c) 2019 Nicolas JUHEL

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

package logger

import (
	"math"
	"strings"

	"github.com/sirupsen/logrus"
)

// Level a uint8 type customized with function to log message with the current log level.
type Level uint8

const (
	// PanicLevel Panic level for entry log, will result on a Panic() call (trace + fatal).
	PanicLevel Level = iota
	// FatalLevel Fatal level for entry log, will result on os.Exit with error.
	FatalLevel
	// ErrorLevel Error level for entry log who's meaning the caller stop his process and return to the pre caller.
	ErrorLevel
	// WarnLevel Warning level for entry log who's meaning the caller don't stop his process and try to continue it.
	WarnLevel
	// InfoLevel Info level for entry log who's meaning it is just an information who's have no impact on caller's process but can be useful to inform human of a state, event, success, ...
	InfoLevel
	// DebugLevel Debug level for entry log who's meaning the caller has no problem and the information is only useful to identify a potential problem who's can arrive later.
	DebugLevel
	// NilLevel Nil level will never log anything and is used to completely disable current log entry. It cannot be used in the SetLogLevel function.
	NilLevel
)

// GetLevelListString return a list ([]string) of all string loglevel available.
func GetLevelListString() []string {
	return []string{
		strings.ToLower(PanicLevel.String()),
		strings.ToLower(FatalLevel.String()),
		strings.ToLower(ErrorLevel.String()),
		strings.ToLower(WarnLevel.String()),
		strings.ToLower(InfoLevel.String()),
		strings.ToLower(DebugLevel.String()),
	}
}

// GetLevelString return a valid Level Type matching the given string parameter.
// If the given parameter don't represent a valid level, the InfoLevel will be return.
/*
	level the string representation of a Level type
*/
func GetLevelString(l string) Level {
	switch {
	case strings.EqualFold(PanicLevel.String(), l):
		return PanicLevel

	case strings.EqualFold(FatalLevel.String(), l):
		return FatalLevel

	case strings.EqualFold(ErrorLevel.String(), l):
		return ErrorLevel

	case strings.EqualFold(WarnLevel.String(), l):
		return WarnLevel

	case strings.EqualFold(InfoLevel.String(), l):
		return InfoLevel

	case strings.EqualFold(DebugLevel.String(), l):
		return DebugLevel
	}

	return InfoLevel
}

// Uint8 Convert the current Level type to a uint8 value. E.g. FatalLevel becomes 1.
func (l Level) Uint8() uint8 {
	return uint8(l)
}

// String Convert the current Level type to a string. E.g. PanicLevel becomes "Critical Error".
func (l Level) String() string {
	//nolint exhaustive
	switch l {
	case DebugLevel:
		return "Debug"
	case InfoLevel:
		return "Info"
	case WarnLevel:
		return "Warning"
	case ErrorLevel:
		return "Error"
	case FatalLevel:
		return "Fatal"
	case PanicLevel:
		return "Critical"
	case NilLevel:
		return ""
	}

	return "unknown"
}

func (l Level) Logrus() logrus.Level {
	switch l {
	case DebugLevel:
		return logrus.DebugLevel
	case InfoLevel:
		return logrus.InfoLevel
	case WarnLevel:
		return logrus.WarnLevel
	case ErrorLevel:
		return logrus.ErrorLevel
	case FatalLevel:
		return logrus.FatalLevel
	case PanicLevel:
		return logrus.PanicLevel
	default:
		return math.MaxInt32
	}
}