package blog4go
import (
"fmt"
"strings"
)
// LevelType type defined for logging level
// just use int
type LevelType int
const (
// level enum 日志枚举
// TRACE trace level
TRACE LevelType = iota
// DEBUG debug level
DEBUG
// INFO info level
INFO
// WARNING warn level
WARNING
// ERROR error level
ERROR
// CRITICAL critical level
CRITICAL
// UNKNOWN unknown level
UNKNOWN = "UNKNOWN"
// DefaultLevel default level for writers
DefaultLevel = TRACE
// PrefixFormat每个消息头前缀
PrefixFormat = " [%s] " //约定格式
// ColoredPrefixFormat 不同日志级别对应不同的颜色消息
ColoredPrefixFormat = " [x1b[%dm%sx1b[0m] " //格式化的颜色
// color enum used in formating color bytes
// NOCOLOR no color
NOCOLOR = 0
// RED red color
RED = 31
// GREEN green color
GREEN = 32
// YELLOW yellow color
YELLOW = 33
// BLUE blue color
BLUE = 34
// GRAY gray color
GRAY = 37
)
var (
// LevelStrings is string present for each level
LevelStrings = [...]string{"TRACE", "DEBUG", "INFO", "WARN", "ERROR", "CRITICAL"}
// StringLevels is map, level strings to levels
StringLevels = map[string]LevelType{"TRACE": TRACE, "DEBUG": DEBUG, "INFO": INFO, "WARN": WARNING, "ERROR": ERROR, "CRITICAL": CRITICAL}
// Levels is a slice consist of all levels
Levels = [...]LevelType{TRACE, DEBUG, INFO, WARNING, ERROR, CRITICAL}
// Prefix is preformatted level prefix string
// help reduce string formatted burden in realtime logging
Prefix = make(map[LevelType]string)
)
func init() {
initPrefix(false) // preformat level prefix string
}
// initPrefix is designed to preformat level prefix string for each level.
// colored decide whether preformat in colored format or not.
// if colored is true, preformat level prefix string in colored format
func initPrefix(colored bool) {
if colored {
Prefix[TRACE] = fmt.Sprintf(ColoredPrefixFormat, GRAY, TRACE.String())
Prefix[DEBUG] = fmt.Sprintf(ColoredPrefixFormat, GREEN, DEBUG.String())
Prefix[INFO] = fmt.Sprintf(ColoredPrefixFormat, BLUE, INFO.String())
Prefix[WARNING] = fmt.Sprintf(ColoredPrefixFormat, YELLOW, WARNING.String())
Prefix[ERROR] = fmt.Sprintf(ColoredPrefixFormat, RED, ERROR.String())
Prefix[CRITICAL] = fmt.Sprintf(ColoredPrefixFormat, RED, CRITICAL.String())
} else {
Prefix[TRACE] = fmt.Sprintf(PrefixFormat, TRACE.String())
Prefix[DEBUG] = fmt.Sprintf(PrefixFormat, DEBUG.String())
Prefix[INFO] = fmt.Sprintf(PrefixFormat, INFO.String())
Prefix[WARNING] = fmt.Sprintf(PrefixFormat, WARNING.String())
Prefix[ERROR] = fmt.Sprintf(PrefixFormat, ERROR.String())
Prefix[CRITICAL] = fmt.Sprintf(PrefixFormat, CRITICAL.String())
}
}
// valid determines whether a Level instance is valid or not
func (level LevelType) valid() bool {
if TRACE > level || CRITICAL < level {
return false
}
return true
}
// String return string format associate with a Level instance
func (level LevelType) String() string {
if !level.valid() {
return UNKNOWN
}
return LevelStrings[level]
}
// prefix return formatted prefix string associate with a Level instance
func (level LevelType) prefix() string {
return Prefix[level]
}
// LevelFromString return Level according to given string
func LevelFromString(str string) LevelType {
level, ok := StringLevels[strings.ToUpper(str)]
if !ok {
return LevelType(-1)
}
return level
}