package logrus import ( "bytes" "fmt" "os" "regexp" "runtime" "strings" "sync" "time" ) var bufferPool *sync.Pool // regex for validation is external, to reduce compilation overhead var matchesLogrus *regexp.Regexp func init() { bufferPool = &sync.Pool{ New: func() interface{} { return new(bytes.Buffer) }, } matchesLogrus, _ = regexp.Compile("logrus.*") } // Defines the key when adding errors using WithError. var ErrorKey = "error" // An entry is the final or intermediate Logrus logging entry. It contains all // the fields passed with WithField{,s}. It's finally logged when Debug, Info, // Warn, Error, Fatal or Panic is called on it. These objects can be reused and // passed around as much as you wish to avoid field duplication. type Entry struct { Logger *Logger // Contains all the fields set by the user. Data Fields // Time at which the log entry was created Time time.Time // Level the log entry was logged at: Debug, Info, Warn, Error, Fatal or Panic Level Level // Calling method, with package name Caller string // Message passed to Debug, Info, Warn, Error, Fatal or Panic Message string // When formatter is called in entry.log(), an Buffer may be set to entry Buffer *bytes.Buffer } func NewEntry(logger *Logger) *Entry { entry := &Entry{ Logger: logger, // Default is three fields, plus one optional. Give a little extra room. Data: make(Fields, 6), } return entry } // Returns the string representation from the reader and ultimately the // formatter. func (entry *Entry) String() (string, error) { serialized, err := entry.Logger.Formatter.Format(entry) if err != nil { return "", err } str := string(serialized) return str, nil } // Add an error as single field (using the key defined in ErrorKey) to the Entry. func (entry *Entry) WithError(err error) *Entry { return entry.WithField(ErrorKey, err) } // Add a single field to the Entry. func (entry *Entry) WithField(key string, value interface{}) *Entry { return entry.WithFields(Fields{key: value}) } // Add a map of fields to the Entry. func (entry *Entry) WithFields(fields Fields) *Entry { data := make(Fields, len(entry.Data)+len(fields)) for k, v := range entry.Data { data[k] = v } for k, v := range fields { data[k] = v } return &Entry{Logger: entry.Logger, Data: data} } // getCaller retrieves the name of the first non-logrus calling function func getCaller() (method string) { // Restrict the lookback to 25 frames - if it's further than that, report UNKNOWN pcs := make([]uintptr, 25) // the first non-logrus caller is at least three frames away depth := runtime.Callers(3, pcs) for i := 0; i < depth; i++ { fullFuncName := runtime.FuncForPC(pcs[i]).Name() idx := strings.LastIndex(fullFuncName, "/") + 1 if idx > 0 { fullFuncName = fullFuncName[idx:] } matched := matchesLogrus.MatchString(fullFuncName) // If the caller isn't part of logrus, we're done if !matched { if fullFuncName == "main.main" { return "main" } else { return fullFuncName } } } // if we got here, we failed to find the caller's context return "UNKNOWN_CALLER" } // This function is not declared with a pointer value because otherwise // race conditions will occur when using multiple goroutines func (entry Entry) log(level Level, msg string) { var buffer *bytes.Buffer entry.Time = time.Now() entry.Level = level entry.Message = msg if ReportCaller() { entry.Caller = getCaller() } if err := entry.Logger.Hooks.Fire(level, &entry); err != nil { entry.Logger.mu.Lock() fmt.Fprintf(os.Stderr, "Failed to fire hook: %v\n", err) entry.Logger.mu.Unlock() } buffer = bufferPool.Get().(*bytes.Buffer) buffer.Reset() defer bufferPool.Put(buffer) entry.Buffer = buffer serialized, err := entry.Logger.Formatter.Format(&entry) entry.Buffer = nil if err != nil { entry.Logger.mu.Lock() fmt.Fprintf(os.Stderr, "Failed to obtain reader, %v\n", err) entry.Logger.mu.Unlock() } else { entry.Logger.mu.Lock() _, err = entry.Logger.Out.Write(serialized) if err != nil { fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err) } entry.Logger.mu.Unlock() } // To avoid Entry#log() returning a value that only would make sense for // panic() to use in Entry#Panic(), we avoid the allocation by checking // directly here. if level <= PanicLevel { panic(&entry) } } func (entry *Entry) Debug(args ...interface{}) { if entry.Logger.Level >= DebugLevel { entry.log(DebugLevel, fmt.Sprint(args...)) } } func (entry *Entry) Print(args ...interface{}) { entry.Info(args...) } func (entry *Entry) Info(args ...interface{}) { if entry.Logger.Level >= InfoLevel { entry.log(InfoLevel, fmt.Sprint(args...)) } } func (entry *Entry) Warn(args ...interface{}) { if entry.Logger.Level >= WarnLevel { entry.log(WarnLevel, fmt.Sprint(args...)) } } func (entry *Entry) Warning(args ...interface{}) { entry.Warn(args...) } func (entry *Entry) Error(args ...interface{}) { if entry.Logger.Level >= ErrorLevel { entry.log(ErrorLevel, fmt.Sprint(args...)) } } func (entry *Entry) Fatal(args ...interface{}) { if entry.Logger.Level >= FatalLevel { entry.log(FatalLevel, fmt.Sprint(args...)) } Exit(1) } func (entry *Entry) Panic(args ...interface{}) { if entry.Logger.Level >= PanicLevel { entry.log(PanicLevel, fmt.Sprint(args...)) } panic(fmt.Sprint(args...)) } // Entry Printf family functions func (entry *Entry) Debugf(format string, args ...interface{}) { if entry.Logger.Level >= DebugLevel { entry.Debug(fmt.Sprintf(format, args...)) } } func (entry *Entry) Infof(format string, args ...interface{}) { if entry.Logger.Level >= InfoLevel { entry.Info(fmt.Sprintf(format, args...)) } } func (entry *Entry) Printf(format string, args ...interface{}) { entry.Infof(format, args...) } func (entry *Entry) Warnf(format string, args ...interface{}) { if entry.Logger.Level >= WarnLevel { entry.Warn(fmt.Sprintf(format, args...)) } } func (entry *Entry) Warningf(format string, args ...interface{}) { entry.Warnf(format, args...) } func (entry *Entry) Errorf(format string, args ...interface{}) { if entry.Logger.Level >= ErrorLevel { entry.Error(fmt.Sprintf(format, args...)) } } func (entry *Entry) Fatalf(format string, args ...interface{}) { if entry.Logger.Level >= FatalLevel { entry.Fatal(fmt.Sprintf(format, args...)) } Exit(1) } func (entry *Entry) Panicf(format string, args ...interface{}) { if entry.Logger.Level >= PanicLevel { entry.Panic(fmt.Sprintf(format, args...)) } } // Entry Println family functions func (entry *Entry) Debugln(args ...interface{}) { if entry.Logger.Level >= DebugLevel { entry.Debug(entry.sprintlnn(args...)) } } func (entry *Entry) Infoln(args ...interface{}) { if entry.Logger.Level >= InfoLevel { entry.Info(entry.sprintlnn(args...)) } } func (entry *Entry) Println(args ...interface{}) { entry.Infoln(args...) } func (entry *Entry) Warnln(args ...interface{}) { if entry.Logger.Level >= WarnLevel { entry.Warn(entry.sprintlnn(args...)) } } func (entry *Entry) Warningln(args ...interface{}) { entry.Warnln(args...) } func (entry *Entry) Errorln(args ...interface{}) { if entry.Logger.Level >= ErrorLevel { entry.Error(entry.sprintlnn(args...)) } } func (entry *Entry) Fatalln(args ...interface{}) { if entry.Logger.Level >= FatalLevel { entry.Fatal(entry.sprintlnn(args...)) } Exit(1) } func (entry *Entry) Panicln(args ...interface{}) { if entry.Logger.Level >= PanicLevel { entry.Panic(entry.sprintlnn(args...)) } } // Sprintlnn => Sprint no newline. This is to get the behavior of how // fmt.Sprintln where spaces are always added between operands, regardless of // their type. Instead of vendoring the Sprintln implementation to spare a // string allocation, we do the simplest thing. func (entry *Entry) sprintlnn(args ...interface{}) string { msg := fmt.Sprintln(args...) return msg[:len(msg)-1] }