Optimise start-up and shut-down

background/ticker.go

@@ -26,7 +26,7 @@ func InitTicker(cfg *helpers.Configuration, stop <-chan struct{}) {
 
 // Runs the ticker and handles tick events
 func runTicker(cfg *helpers.Configuration, stop <-chan struct{}) {
-	log.Info("Starting background ticker", zap.Duration("frequency", frequency))
+	log.Info("Starting background task ticker", zap.Duration("frequency", frequency))
 	ticker := time.NewTicker(frequency)
 	defer ticker.Stop()
 

dbAccess/client.go

@@ -36,7 +36,7 @@ func InitDataAccess(cfg *helpers.Configuration) {
 		fmt.Println(err)
 		log.Fatal("Error connecting to database: " + err.Error())
 	} else {
-		log.Info("Database connection successful")
+		log.Info("Database connection initialising")
 	}
 	MongoClient = client
 }

log/log.go

@@ -7,27 +7,28 @@ import (
 	"go.uber.org/zap/zapcore"
 )
 
-// Logger object is exported to facilitate migration
+// Use outside `package log`
-// to the single logger instance.  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()
+}

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"fmt"
 	"os"
 	"os/signal"
 	"syscall"
@@ -18,7 +19,14 @@ import (
 	"go.uber.org/zap"
 )
 
+func init() {
+	printStartupBanner()
+	fmt.Println("Version", helpers.Version, "\n\n")
+}
+
 func main() {
+	log.InitLogger()
+	defer log.Cleanup()
 	log.Info("Initialising OwlBoard timetable-mgr", zap.String("version", helpers.Version))
 	cfg, err := helpers.LoadConfig()
 	if err != nil {
@@ -82,5 +90,26 @@ func cleanup(cfg *helpers.Configuration, stop chan<- struct{}) {
 
 	time.Sleep(500 * time.Millisecond)
 
+	log.Cleanup()
+
 	os.Exit(0)
 }
+
+func printStartupBanner() {
+	art := `
+  ___           _ ____                      _                          
+ / _ \__      _| | __ )  ___   __ _ _ __ __| |                         
+| | | \ \ /\ / / |  _ \ / _ \ / _' | '__/ _' |                         
+| |_| |\ V  V /| | |_) | (_) | (_| | | | (_| |                         
+ \___/  \_/\_/ |_|____/ \___/ \__,_|_|  \__,_|                         
+
+ _   _                _        _     _                                 
+| |_(_)_ __ ___   ___| |_ __ _| |__ | | ___       _ __ ___   __ _ _ __ 
+| __| | '_ ' _ \ / _ \ __/ _' | '_ \| |/ _ \_____| '_ ' _ \ / _' | '__|
+| |_| | | | | | |  __/ || (_| | |_) | |  __/_____| | | | | | (_| | |   
+ \__|_|_| |_| |_|\___|\__\__,_|_.__/|_|\___|     |_| |_| |_|\__, |_|   
+                                                            |___/      
+	`
+
+	fmt.Println(art)
+}