Optimized logger to check for month change

mod/info/logger/logger.go

@@ -17,8 +17,11 @@ import (
 */
 
 type Logger struct {
-	LogToFile bool
-	file      *os.File
+	LogToFile      bool   //Set enable write to file
+	Prefix         string //Prefix for log files
+	LogFolder      string //Folder to store the log  file
+	CurrentLogFile string //Current writing filename
+	file           *os.File
 }
 
 func NewLogger(logFilePrefix string, logFolder string, logToFile bool) (*Logger, error) {
@@ -26,18 +29,29 @@ func NewLogger(logFilePrefix string, logFolder string, logToFile bool) (*Logger,
 	if err != nil {
 		return nil, err
 	}
-	year, month, _ := time.Now().Date()
-	logFilePath := filepath.Join(logFolder, logFilePrefix+"_"+strconv.Itoa(year)+"-"+strconv.Itoa(int(month))+".log")
+
+	thisLogger := Logger{
+		LogToFile: logToFile,
+		Prefix:    logFilePrefix,
+		LogFolder: logFolder,
+	}
+
+	logFilePath := thisLogger.getLogFilepath()
 	f, err := os.OpenFile(logFilePath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0755)
 	if err != nil {
 		return nil, err
 	}
-	return &Logger{
-		LogToFile: logToFile,
-		file:      f,
-	}, nil
+	thisLogger.CurrentLogFile = logFilePath
+	thisLogger.file = f
+	return &thisLogger, nil
 }
 
+func (l *Logger) getLogFilepath() string {
+	year, month, _ := time.Now().Date()
+	return filepath.Join(l.LogFolder, l.Prefix+"_"+strconv.Itoa(year)+"-"+strconv.Itoa(int(month))+".log")
+}
+
+//PrintAndLog will log the message to file and print the log to STDOUT
 func (l *Logger) PrintAndLog(title string, message string, originalError error) {
 	go func() {
 		l.Log(title, message, originalError)
@@ -46,13 +60,31 @@ func (l *Logger) PrintAndLog(title string, message string, originalError error)
 }
 
 func (l *Logger) Log(title string, errorMessage string, originalError error) {
+	l.ValidateAndUpdateLogFilepath()
 	if l.LogToFile {
 		if originalError == nil {
 			l.file.WriteString(time.Now().Format("2006-01-02 15:04:05.000000") + "|" + fmt.Sprintf("%-16s", title) + " [INFO]" + errorMessage + "\n")
 		} else {
 			l.file.WriteString(time.Now().Format("2006-01-02 15:04:05.000000") + "|" + fmt.Sprintf("%-16s", title) + " [ERROR]" + errorMessage + " " + originalError.Error() + "\n")
 		}
+	}
 
+}
+
+//Validate if the logging target is still valid (detect any months change)
+func (l *Logger) ValidateAndUpdateLogFilepath() {
+	expectedCurrentLogFilepath := l.getLogFilepath()
+	if l.CurrentLogFile != expectedCurrentLogFilepath {
+		//Change of month. Update to a new log file
+		l.file.Close()
+		f, err := os.OpenFile(expectedCurrentLogFilepath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0755)
+		if err != nil {
+			log.Println("[Logger] Unable to create new log. Logging to file disabled.")
+			l.LogToFile = false
+			return
+		}
+		l.CurrentLogFile = expectedCurrentLogFilepath
+		l.file = f
 	}
 }