-
Notifications
You must be signed in to change notification settings - Fork 213
/
jsonfilelog.go
161 lines (145 loc) · 3.74 KB
/
jsonfilelog.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
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
// Package jsonfilelog provides the default Logger implementation for
// Docker logging. This logger logs to files on the host server in the
// JSON format.
package jsonfilelog
import (
"bytes"
"encoding/json"
"fmt"
"strconv"
"sync"
"github.com/docker/docker/daemon/logger"
"github.com/docker/docker/daemon/logger/jsonfilelog/jsonlog"
"github.com/docker/docker/daemon/logger/loggerutils"
units "github.com/docker/go-units"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
// Name is the name of the file that the jsonlogger logs to.
const Name = "json-file"
// JSONFileLogger is Logger implementation for default Docker logging.
type JSONFileLogger struct {
mu sync.Mutex
closed bool
writer *loggerutils.LogFile
readers map[*logger.LogWatcher]struct{} // stores the active log followers
}
func init() {
if err := logger.RegisterLogDriver(Name, New); err != nil {
logrus.Fatal(err)
}
if err := logger.RegisterLogOptValidator(Name, ValidateLogOpt); err != nil {
logrus.Fatal(err)
}
}
// New creates new JSONFileLogger which writes to filename passed in
// on given context.
func New(info logger.Info) (logger.Logger, error) {
var capval int64 = -1
if capacity, ok := info.Config["max-size"]; ok {
var err error
capval, err = units.FromHumanSize(capacity)
if err != nil {
return nil, err
}
}
var maxFiles = 1
if maxFileString, ok := info.Config["max-file"]; ok {
var err error
maxFiles, err = strconv.Atoi(maxFileString)
if err != nil {
return nil, err
}
if maxFiles < 1 {
return nil, fmt.Errorf("max-file cannot be less than 1")
}
}
var extra []byte
attrs, err := info.ExtraAttributes(nil)
if err != nil {
return nil, err
}
if len(attrs) > 0 {
var err error
extra, err = json.Marshal(attrs)
if err != nil {
return nil, err
}
}
buf := bytes.NewBuffer(nil)
marshalFunc := func(msg *logger.Message) ([]byte, error) {
if err := marshalMessage(msg, extra, buf); err != nil {
return nil, err
}
b := buf.Bytes()
buf.Reset()
return b, nil
}
writer, err := loggerutils.NewLogFile(info.LogPath, capval, maxFiles, marshalFunc, decodeFunc)
if err != nil {
return nil, err
}
return &JSONFileLogger{
writer: writer,
readers: make(map[*logger.LogWatcher]struct{}),
}, nil
}
// Log converts logger.Message to jsonlog.JSONLog and serializes it to file.
func (l *JSONFileLogger) Log(msg *logger.Message) error {
l.mu.Lock()
err := l.writer.WriteLogEntry(msg)
l.mu.Unlock()
return err
}
func marshalMessage(msg *logger.Message, extra json.RawMessage, buf *bytes.Buffer) error {
logLine := msg.Line
if !msg.Partial {
logLine = append(msg.Line, '\n')
}
err := (&jsonlog.JSONLogs{
Log: logLine,
Stream: msg.Source,
Created: msg.Timestamp,
RawAttrs: extra,
}).MarshalJSONBuf(buf)
if err != nil {
return errors.Wrap(err, "error writing log message to buffer")
}
err = buf.WriteByte('\n')
return errors.Wrap(err, "error finalizing log buffer")
}
// ValidateLogOpt looks for json specific log options max-file & max-size.
func ValidateLogOpt(cfg map[string]string) error {
for key := range cfg {
switch key {
case "max-file":
case "max-size":
case "labels":
case "env":
case "env-regex":
default:
return fmt.Errorf("unknown log opt '%s' for json-file log driver", key)
}
}
return nil
}
// LogPath returns the location the given json logger logs to.
func (l *JSONFileLogger) LogPath() string {
return l.writer.LogPath()
}
// Close closes underlying file and signals all readers to stop.
func (l *JSONFileLogger) Close() error {
l.mu.Lock()
l.closed = true
err := l.writer.Close()
for r := range l.readers {
r.Close()
delete(l.readers, r)
}
l.mu.Unlock()
return err
}
// Name returns name of this logger.
func (l *JSONFileLogger) Name() string {
return Name
}