110 lines
2.1 KiB
Go
110 lines
2.1 KiB
Go
// Copyright 2016 Google Inc. All rights reserved.
|
|
// Use of this source code is governed by the Apache 2.0
|
|
// license that can be found in the LICENSE file.
|
|
|
|
// +build !appengine
|
|
|
|
package internal
|
|
|
|
import (
|
|
"encoding/json"
|
|
"fmt"
|
|
"io"
|
|
"io/ioutil"
|
|
"log"
|
|
"os"
|
|
"strings"
|
|
"sync"
|
|
"time"
|
|
)
|
|
|
|
// jsonLogger writes logs in the JSON format required for Flex Logging. It can
|
|
// be used concurrently.
|
|
type jsonLogger struct {
|
|
mu sync.Mutex
|
|
enc *json.Encoder
|
|
}
|
|
|
|
type logLine struct {
|
|
Message string `json:"message"`
|
|
Timestamp logTimestamp `json:"timestamp"`
|
|
Severity string `json:"severity"`
|
|
TraceID string `json:"traceId,omitempty"`
|
|
}
|
|
|
|
type logTimestamp struct {
|
|
Seconds int64 `json:"seconds"`
|
|
Nanos int `json:"nanos"`
|
|
}
|
|
|
|
var (
|
|
logger *jsonLogger
|
|
loggerOnce sync.Once
|
|
|
|
logPath = "/var/log/app_engine/app.json"
|
|
stderrLogger = newJSONLogger(os.Stderr)
|
|
testLogger = newJSONLogger(ioutil.Discard)
|
|
|
|
levels = map[int64]string{
|
|
0: "DEBUG",
|
|
1: "INFO",
|
|
2: "WARNING",
|
|
3: "ERROR",
|
|
4: "CRITICAL",
|
|
}
|
|
)
|
|
|
|
func globalLogger() *jsonLogger {
|
|
loggerOnce.Do(func() {
|
|
f, err := os.OpenFile(logPath, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0666)
|
|
if err != nil {
|
|
log.Printf("failed to open/create log file, logging to stderr: %v", err)
|
|
logger = stderrLogger
|
|
return
|
|
}
|
|
|
|
logger = newJSONLogger(f)
|
|
})
|
|
|
|
return logger
|
|
}
|
|
|
|
func logf(ctx *context, level int64, format string, args ...interface{}) {
|
|
s := strings.TrimSpace(fmt.Sprintf(format, args...))
|
|
now := time.Now()
|
|
|
|
trace := ctx.req.Header.Get(traceHeader)
|
|
if i := strings.Index(trace, "/"); i > -1 {
|
|
trace = trace[:i]
|
|
}
|
|
|
|
line := &logLine{
|
|
Message: s,
|
|
Timestamp: logTimestamp{
|
|
Seconds: now.Unix(),
|
|
Nanos: now.Nanosecond(),
|
|
},
|
|
Severity: levels[level],
|
|
TraceID: trace,
|
|
}
|
|
|
|
if err := ctx.logger.emit(line); err != nil {
|
|
log.Printf("failed to write log line to file: %v", err)
|
|
}
|
|
|
|
log.Print(levels[level] + ": " + s)
|
|
}
|
|
|
|
func newJSONLogger(w io.Writer) *jsonLogger {
|
|
return &jsonLogger{
|
|
enc: json.NewEncoder(w),
|
|
}
|
|
}
|
|
|
|
func (l *jsonLogger) emit(line *logLine) error {
|
|
l.mu.Lock()
|
|
defer l.mu.Unlock()
|
|
|
|
return l.enc.Encode(line)
|
|
}
|