refactor(logging): add routine to create and use log file based on ap…

…p start time

app.core.go

@@ -34,19 +34,19 @@ type App struct {
 }
 
 // NewApp provides an instance of App.
-func NewApp() (AppProvider, error) {
+func NewApp(start time.Time) (AppProvider, error) {
 	var app *App
 	config, err := LoadAndInitConfigs(GitCommit, GitTag, BuildTime)
 	if err != nil {
 		return nil, fmt.Errorf("failed to setup app configuration: %s", err)
 	}
 
 	// ensure the logs folder exists and Setup the logging module.
-	err = os.MkdirAll(filepath.Dir(config.LogFile), 0o700)
+	err = os.MkdirAll(config.LogFolder, 0o700)
 	if err != nil {
-		return nil, fmt.Errorf("failed to create logging folder: %s", err)
+		return nil, fmt.Errorf("logging: failed to create folder: %v", err)
 	}
-	logFile, err := os.OpenFile(config.LogFile, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
+	logFile, err := os.OpenFile(createLogFilePath(config.LogFolder, start), os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0o644)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create logging file: %s", err)
 	}
@@ -76,7 +76,7 @@ func NewApp() (AppProvider, error) {
 	boltDBConsumer := NewBoltDBConsumer(logger, redisQueue, boltBookStorage)
 
 	bookService := NewBookService(logger, config, NewClock(), redisBookStorage, boltBookStorage, redisQueue)
-	stats := NewStatistics(config.GitTag, config.GitCommit, runtime.Version(), runtime.GOOS+"/"+runtime.GOARCH, IsAppRunningInDocker(), time.Now())
+	stats := NewStatistics(config.GitTag, config.GitCommit, runtime.Version(), runtime.GOOS+"/"+runtime.GOARCH, IsAppRunningInDocker(), start)
 	apiService := NewAPIHandler(logger, config, stats, NewClock(), NewIDsHandler(), bookService)
 
 	// Build the map of middlewares stacks.
@@ -211,3 +211,9 @@ func (app *App) ConsumeQueues(gCtx context.Context, g *errgroup.Group) func() er
 		return nil
 	}
 }
+
+// createLogFilePath returns the absolute path of the initial log file.
+func createLogFilePath(folder string, t time.Time) string {
+	suffix := fmt.Sprintf("%02d%02d%02d.%02d%02d%02d.log", t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(), t.Second())
+	return filepath.Join(folder, suffix)
+}

main.go

@@ -2,10 +2,11 @@ package main
 
 import (
 	"log"
+	"time"
 )
 
 func main() {
-	app, err := NewApp()
+	app, err := NewApp(time.Now())
 	if err != nil {
 		log.Fatalf("app failed: %v", err)
 	}