-
Notifications
You must be signed in to change notification settings - Fork 7
/
logging.go
127 lines (104 loc) · 2.8 KB
/
logging.go
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
// Copyright 2021 the GitHub Workflow Job to PubSub 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 logging
import (
"encoding/json"
"fmt"
"io"
"os"
"time"
)
type Severity string
const (
SeverityDebug Severity = "DEBUG"
SeverityInfo Severity = "INFO"
SeverityWarn Severity = "WARNING"
SeverityError Severity = "ERROR"
SeverityFatal Severity = "EMERGENCY"
)
type Logger struct {
stdout io.Writer
stderr io.Writer
}
func NewLogger(outw, errw io.Writer) *Logger {
return &Logger{stdout: outw, stderr: errw}
}
func (l *Logger) Debug(msg string, fields ...interface{}) {
l.log(l.stdout, msg, SeverityDebug, fields...)
}
func (l *Logger) Info(msg string, fields ...interface{}) {
l.log(l.stdout, msg, SeverityInfo, fields...)
}
func (l *Logger) Warn(msg string, fields ...interface{}) {
l.log(l.stdout, msg, SeverityWarn, fields...)
}
func (l *Logger) Error(msg string, fields ...interface{}) {
l.log(l.stderr, msg, SeverityError, fields...)
}
func (l *Logger) Fatal(msg string, fields ...interface{}) {
l.log(l.stderr, msg, SeverityFatal, fields...)
os.Exit(1)
}
func (l *Logger) log(w io.Writer, msg string, sev Severity, fields ...interface{}) {
if len(fields)%2 != 0 {
panic("number of fields must be even")
}
data := make(map[string]interface{}, len(fields)/2)
for i := 0; i < len(fields); i += 2 {
key, ok := fields[i].(string)
if !ok {
panic(fmt.Errorf("field %d is not a string (%T, %q)", i, fields[i], fields[i]))
}
switch typ := fields[i+1].(type) {
case error:
data[key] = typ.Error()
default:
data[key] = typ
}
}
jsonPayload, err := json.Marshal(&LogEntry{
Time: timePtr(time.Now().UTC()),
Severity: sev,
Message: msg,
Data: data,
})
if err != nil {
panic(fmt.Errorf("failed to marshal log entry: %w", err))
}
fmt.Fprintln(w, string(jsonPayload))
}
type LogEntry struct {
Time *time.Time
Severity Severity
Message string
Data map[string]interface{}
}
func (l *LogEntry) MarshalJSON() ([]byte, error) {
d := make(map[string]interface{}, 8)
if l.Time != nil {
d["time"] = l.Time.Format(time.RFC3339)
}
d["severity"] = string(l.Severity)
d["message"] = l.Message
for k, v := range l.Data {
d[k] = v
}
return json.Marshal(d)
}
func timePtr(t time.Time) *time.Time {
if t.IsZero() {
return nil
}
return &t
}