moby--moby/daemon/logger/jsonfilelog/jsonfilelog.go

50 lines
1.1 KiB
Go

package jsonfilelog
import (
"bytes"
"os"
"github.com/docker/docker/daemon/logger"
"github.com/docker/docker/pkg/jsonlog"
)
// JSONFileLogger is Logger implementation for default docker logging:
// JSON objects to file
type JSONFileLogger struct {
buf *bytes.Buffer
f *os.File // store for closing
}
// New creates new JSONFileLogger which writes to filename
func New(filename string) (logger.Logger, error) {
log, err := os.OpenFile(filename, os.O_RDWR|os.O_APPEND|os.O_CREATE, 0600)
if err != nil {
return nil, err
}
return &JSONFileLogger{
f: log,
buf: bytes.NewBuffer(nil),
}, nil
}
// Log converts logger.Message to jsonlog.JSONLog and serializes it to file
func (l *JSONFileLogger) Log(msg *logger.Message) error {
err := (&jsonlog.JSONLog{Log: string(msg.Line) + "\n", Stream: msg.Source, Created: msg.Timestamp}).MarshalJSONBuf(l.buf)
if err != nil {
return err
}
l.buf.WriteByte('\n')
_, err = l.buf.WriteTo(l.f)
return err
}
// Close closes underlying file
func (l *JSONFileLogger) Close() error {
return l.f.Close()
}
// Name returns name of this logger
func (l *JSONFileLogger) Name() string {
return "JSONFile"
}