implement graceful shutdown

cmd/server/main.go

@@ -1,9 +1,13 @@
 package main
 
 import (
+	"context"
 	"log"
 	"os"
+	"os/signal"
 	"strconv"
+	"syscall"
+	"time"
 
 	"github.com/Henelik/cms/internal/content"
 	"github.com/Henelik/cms/pkg/config"
@@ -37,5 +41,32 @@ func main() {
 	content.RegisterRoutes(app)
 	public.RegisterRoutes(app)
 
-	app.Listen(":" + strconv.Itoa(cfg.ServerPort))
+	go func() {
+		if err := app.Listen(":" + strconv.Itoa(cfg.ServerPort)); err != nil {
+			log.Panic(err.Error())
+		}
+	}()
+
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
+	<-quit
+
+	log.Println("shutting down server...")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	if err := app.ShutdownWithContext(ctx); err != nil {
+		log.Printf("server forced to shutdown: %v", err)
+	}
+
+	if sqlDB, err := db.DB(); err == nil {
+		if err := sqlDB.Close(); err != nil {
+			log.Printf("failed to close database: %v", err)
+		}
+	} else {
+		log.Printf("failed to get underlying sql.DB: %v", err)
+	}
+
+	log.Println("server exited")
 }