Initial commit

vendor/github.com/hyperhq/hypercli/daemon/logger/jsonfilelog/jsonfilelog.go

@@ -0,0 +1,147 @@
+// 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/Sirupsen/logrus"
+	"github.com/hyperhq/hypercli/daemon/logger"
+	"github.com/hyperhq/hypercli/daemon/logger/loggerutils"
+	"github.com/hyperhq/hypercli/pkg/jsonlog"
+	"github.com/docker/go-units"
+)
+
+// 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 {
+	buf     *bytes.Buffer
+	writer  *loggerutils.RotateFileWriter
+	mu      sync.Mutex
+	ctx     logger.Context
+	readers map[*logger.LogWatcher]struct{} // stores the active log followers
+	extra   []byte                          // json-encoded extra attributes
+}
+
+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(ctx logger.Context) (logger.Logger, error) {
+	var capval int64 = -1
+	if capacity, ok := ctx.Config["max-size"]; ok {
+		var err error
+		capval, err = units.FromHumanSize(capacity)
+		if err != nil {
+			return nil, err
+		}
+	}
+	var maxFiles = 1
+	if maxFileString, ok := ctx.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")
+		}
+	}
+
+	writer, err := loggerutils.NewRotateFileWriter(ctx.LogPath, capval, maxFiles)
+	if err != nil {
+		return nil, err
+	}
+
+	var extra []byte
+	if attrs := ctx.ExtraAttributes(nil); len(attrs) > 0 {
+		var err error
+		extra, err = json.Marshal(attrs)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &JSONFileLogger{
+		buf:     bytes.NewBuffer(nil),
+		writer:  writer,
+		readers: make(map[*logger.LogWatcher]struct{}),
+		extra:   extra,
+	}, nil
+}
+
+// Log converts logger.Message to jsonlog.JSONLog and serializes it to file.
+func (l *JSONFileLogger) Log(msg *logger.Message) error {
+	timestamp, err := jsonlog.FastTimeMarshalJSON(msg.Timestamp)
+	if err != nil {
+		return err
+	}
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	err = (&jsonlog.JSONLogs{
+		Log:      append(msg.Line, '\n'),
+		Stream:   msg.Source,
+		Created:  timestamp,
+		RawAttrs: l.extra,
+	}).MarshalJSONBuf(l.buf)
+	if err != nil {
+		return err
+	}
+
+	l.buf.WriteByte('\n')
+	_, err = l.writer.Write(l.buf.Bytes())
+	l.buf.Reset()
+
+	return err
+}
+
+// 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":
+		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()
+	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
+}