forgejo/modules/log/level.go
Ivan Shapovalov 012a1e0497 log: journald integration (#2869)
Provide a bit more journald integration. Specifically:

- support emission of printk-style log level prefixes, documented in [`sd-daemon`(3)](https://man7.org/linux/man-pages/man3/sd-daemon.3.html#DESCRIPTION), that allow journald to automatically annotate stderr log lines with their level;
- add a new "journaldflags" item that is supposed to be used in place of "stdflags" when under journald to reduce log clutter (i. e. strip date/time info to avoid duplication, and use log level prefixes instead of textual log levels);
- detect whether stderr and/or stdout are attached to journald by parsing `$JOURNAL_STREAM` environment variable and adjust console logger defaults accordingly.

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## Draft release notes
<!--URL:https://codeberg.org/forgejo/forgejo-->
- Features
  - [PR](https://codeberg.org/forgejo/forgejo/pulls/2869): <!--number 2869 --><!--line 0 --><!--description bG9nOiBqb3VybmFsZCBpbnRlZ3JhdGlvbg==-->log: journald integration<!--description-->
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Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/2869
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: Ivan Shapovalov <intelfx@intelfx.name>
Co-committed-by: Ivan Shapovalov <intelfx@intelfx.name>
2024-08-09 07:49:13 +00:00

136 lines
2.7 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package log
import (
"bytes"
"strings"
"code.gitea.io/gitea/modules/json"
)
// Level is the level of the logger
type Level int
const (
UNDEFINED Level = iota
TRACE
DEBUG
INFO
WARN
ERROR
FATAL
NONE
)
const CRITICAL = ERROR // most logger frameworks doesn't support CRITICAL, and it doesn't seem useful
var toString = map[Level]string{
UNDEFINED: "undefined",
TRACE: "trace",
DEBUG: "debug",
INFO: "info",
WARN: "warn",
ERROR: "error",
FATAL: "fatal",
NONE: "none",
}
// Machine-readable log level prefixes as defined in sd-daemon(3).
//
// "If a systemd service definition file is configured with StandardError=journal
// or StandardError=kmsg (and similar with StandardOutput=), these prefixes can
// be used to encode a log level in lines printed. <...> To use these prefixes
// simply prefix every line with one of these strings. A line that is not prefixed
// will be logged at the default log level SD_INFO."
var toJournalPrefix = map[Level]string{
TRACE: "<7>", // SD_DEBUG
DEBUG: "<6>", // SD_INFO
INFO: "<5>", // SD_NOTICE
WARN: "<4>", // SD_WARNING
ERROR: "<3>", // SD_ERR
FATAL: "<2>", // SD_CRIT
}
var toLevel = map[string]Level{
"undefined": UNDEFINED,
"trace": TRACE,
"debug": DEBUG,
"info": INFO,
"warn": WARN,
"warning": WARN,
"error": ERROR,
"fatal": FATAL,
"none": NONE,
}
var levelToColor = map[Level][]ColorAttribute{
TRACE: {Bold, FgCyan},
DEBUG: {Bold, FgBlue},
INFO: {Bold, FgGreen},
WARN: {Bold, FgYellow},
ERROR: {Bold, FgRed},
FATAL: {Bold, BgRed},
NONE: {Reset},
}
func (l Level) String() string {
s, ok := toString[l]
if ok {
return s
}
return "info"
}
func (l Level) JournalPrefix() string {
return toJournalPrefix[l]
}
func (l Level) ColorAttributes() []ColorAttribute {
color, ok := levelToColor[l]
if ok {
return color
}
none := levelToColor[NONE]
return none
}
// MarshalJSON takes a Level and turns it into text
func (l Level) MarshalJSON() ([]byte, error) {
buffer := bytes.NewBufferString(`"`)
buffer.WriteString(toString[l])
buffer.WriteString(`"`)
return buffer.Bytes(), nil
}
// UnmarshalJSON takes text and turns it into a Level
func (l *Level) UnmarshalJSON(b []byte) error {
var tmp any
err := json.Unmarshal(b, &tmp)
if err != nil {
return err
}
switch v := tmp.(type) {
case string:
*l = LevelFromString(v)
case int:
*l = LevelFromString(Level(v).String())
default:
*l = INFO
}
return nil
}
// LevelFromString takes a level string and returns a Level
func LevelFromString(level string) Level {
if l, ok := toLevel[strings.ToLower(level)]; ok {
return l
}
return INFO
}