1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
// Copyright 2017 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package promlog defines standardised ways to initialize Go kit loggers
// across Prometheus components.
// It should typically only ever be imported by main packages.
package promlog
import (
"os"
"sync"
"time"
"github.com/go-kit/log"
"github.com/go-kit/log/level"
"github.com/pkg/errors"
)
var (
// This timestamp format differs from RFC3339Nano by using .000 instead
// of .999999999 which changes the timestamp from 9 variable to 3 fixed
// decimals (.130 instead of .130987456).
timestampFormat = log.TimestampFormat(
func() time.Time { return time.Now().UTC() },
"2006-01-02T15:04:05.000Z07:00",
)
)
// AllowedLevel is a settable identifier for the minimum level a log entry
// must be have.
type AllowedLevel struct {
s string
o level.Option
}
func (l *AllowedLevel) UnmarshalYAML(unmarshal func(interface{}) error) error {
var s string
type plain string
if err := unmarshal((*plain)(&s)); err != nil {
return err
}
if s == "" {
return nil
}
lo := &AllowedLevel{}
if err := lo.Set(s); err != nil {
return err
}
*l = *lo
return nil
}
func (l *AllowedLevel) String() string {
return l.s
}
// Set updates the value of the allowed level.
func (l *AllowedLevel) Set(s string) error {
switch s {
case "debug":
l.o = level.AllowDebug()
case "info":
l.o = level.AllowInfo()
case "warn":
l.o = level.AllowWarn()
case "error":
l.o = level.AllowError()
default:
return errors.Errorf("unrecognized log level %q", s)
}
l.s = s
return nil
}
// AllowedFormat is a settable identifier for the output format that the logger can have.
type AllowedFormat struct {
s string
}
func (f *AllowedFormat) String() string {
return f.s
}
// Set updates the value of the allowed format.
func (f *AllowedFormat) Set(s string) error {
switch s {
case "logfmt", "json":
f.s = s
default:
return errors.Errorf("unrecognized log format %q", s)
}
return nil
}
// Config is a struct containing configurable settings for the logger
type Config struct {
Level *AllowedLevel
Format *AllowedFormat
}
// New returns a new leveled oklog logger. Each logged line will be annotated
// with a timestamp. The output always goes to stderr.
func New(config *Config) log.Logger {
var l log.Logger
if config.Format != nil && config.Format.s == "json" {
l = log.NewJSONLogger(log.NewSyncWriter(os.Stderr))
} else {
l = log.NewLogfmtLogger(log.NewSyncWriter(os.Stderr))
}
if config.Level != nil {
l = log.With(l, "ts", timestampFormat, "caller", log.Caller(5))
l = level.NewFilter(l, config.Level.o)
} else {
l = log.With(l, "ts", timestampFormat, "caller", log.DefaultCaller)
}
return l
}
// NewDynamic returns a new leveled logger. Each logged line will be annotated
// with a timestamp. The output always goes to stderr. Some properties can be
// changed, like the level.
func NewDynamic(config *Config) *logger {
var l log.Logger
if config.Format != nil && config.Format.s == "json" {
l = log.NewJSONLogger(log.NewSyncWriter(os.Stderr))
} else {
l = log.NewLogfmtLogger(log.NewSyncWriter(os.Stderr))
}
lo := &logger{
base: l,
leveled: l,
}
if config.Level != nil {
lo.SetLevel(config.Level)
}
return lo
}
type logger struct {
base log.Logger
leveled log.Logger
currentLevel *AllowedLevel
mtx sync.Mutex
}
// Log implements logger.Log.
func (l *logger) Log(keyvals ...interface{}) error {
l.mtx.Lock()
defer l.mtx.Unlock()
return l.leveled.Log(keyvals...)
}
// SetLevel changes the log level.
func (l *logger) SetLevel(lvl *AllowedLevel) {
l.mtx.Lock()
defer l.mtx.Unlock()
if lvl == nil {
l.leveled = log.With(l.base, "ts", timestampFormat, "caller", log.DefaultCaller)
l.currentLevel = nil
return
}
if l.currentLevel != nil && l.currentLevel.s != lvl.s {
_ = l.base.Log("msg", "Log level changed", "prev", l.currentLevel, "current", lvl)
}
l.currentLevel = lvl
l.leveled = level.NewFilter(log.With(l.base, "ts", timestampFormat, "caller", log.Caller(5)), lvl.o)
}
|
