Optimise start-up and shut-down

log/log.go

@@ -7,27 +7,28 @@ import (
 	"go.uber.org/zap/zapcore"
 )
 
-// Logger object is exported to facilitate migration
-// to the single logger instance.  Use outside `package log`
+// Use outside `package log`
 // should be avoided.
 var post *zap.Logger
 
 // Initialises the logger
-func init() {
+func InitLogger() {
 	var err error
 	mode := os.Getenv("runtime")
 	if mode == "" {
 		mode = "prod"
 	}
 
-	logLevel := zapcore.InfoLevel
+	var level zapcore.Level
 	if mode == "debug" {
-		logLevel = zapcore.DebugLevel
+		level = zap.DebugLevel
+	} else {
+		level = zap.InfoLevel
 	}
 
 	config := zap.NewDevelopmentConfig()
 	config.EncoderConfig.EncodeLevel = zapcore.CapitalColorLevelEncoder
-	config.Level = zap.NewAtomicLevelAt(logLevel)
+	config.Level = zap.NewAtomicLevelAt(level)
 	post, err = config.Build(zap.AddCallerSkip(1))
 	if err != nil {
 		panic("Failed to initialize logger: " + err.Error())
@@ -35,29 +36,41 @@ func init() {
 
 	defer post.Sync()
 
-	Info("Logger initialised", zap.String("level", logLevel.String()), zap.String("runtime", mode))
+	Info("Logger initialised", zap.String("level", level.String()), zap.String("runtime", mode))
 }
 
+// Logs message at info level
 func Info(msg string, fields ...zap.Field) {
 	post.Info(msg, fields...)
 }
 
+// Logs message at debug level
 func Debug(msg string, fields ...zap.Field) {
 	post.Debug(msg, fields...)
 }
 
+// Logs message at warn level
 func Warn(msg string, fields ...zap.Field) {
 	post.Warn(msg, fields...)
 }
 
+// Logs message at error level
 func Error(msg string, fields ...zap.Field) {
 	post.Error(msg, fields...)
 }
 
+// Logs message at fatal level then call os.exit(1)
 func Fatal(msg string, fields ...zap.Field) {
 	post.Fatal(msg, fields...)
 }
 
+// Logs message at panic level the panics
 func Panic(msg string, fields ...zap.Field) {
 	post.Panic(msg, fields...)
 }
+
+// Flushes log messages
+func Cleanup() {
+	Info("Flushing log messages")
+	post.Sync()
+}