containerd/log.go

111 lines
1.8 KiB
Go

package containerd
import (
"encoding/json"
"io"
"os"
"path/filepath"
"sync"
"time"
"github.com/Sirupsen/logrus"
)
type logConfig struct {
BundlePath string
LogSize int64 // in bytes
Stdin io.WriteCloser
Stdout io.ReadCloser
Stderr io.ReadCloser
}
func newLogger(i *logConfig) (*logger, error) {
l := &logger{
config: i,
messages: make(chan *Message, DefaultBufferSize),
}
f, err := os.OpenFile(
filepath.Join(l.config.BundlePath, "logs.json"),
os.O_CREATE|os.O_WRONLY|os.O_APPEND,
0655,
)
if err != nil {
return nil, err
}
l.f = f
hout := &logHandler{
stream: "stdout",
messages: l.messages,
}
herr := &logHandler{
stream: "stderr",
messages: l.messages,
}
go func() {
io.Copy(hout, i.Stdout)
}()
go func() {
io.Copy(herr, i.Stderr)
}()
l.start()
return l, nil
}
type Message struct {
Stream string `json:"stream"`
Timestamp time.Time `json:"timestamp"`
Data []byte `json:"data"`
}
type logger struct {
config *logConfig
f *os.File
wg sync.WaitGroup
messages chan *Message
}
type logHandler struct {
stream string
messages chan *Message
}
func (h *logHandler) Write(b []byte) (int, error) {
h.messages <- &Message{
Stream: h.stream,
Timestamp: time.Now(),
Data: b,
}
return len(b), nil
}
func (l *logger) start() {
l.wg.Add(1)
go func() {
l.wg.Done()
enc := json.NewEncoder(l.f)
for m := range l.messages {
if err := enc.Encode(m); err != nil {
logrus.WithField("error", err).Error("write log message")
}
}
}()
}
func (l *logger) Close() (err error) {
for _, c := range []io.Closer{
l.config.Stdin,
l.config.Stdout,
l.config.Stderr,
} {
if cerr := c.Close(); err == nil {
err = cerr
}
}
close(l.messages)
l.wg.Wait()
if ferr := l.f.Close(); err == nil {
err = ferr
}
return err
}