From b57d1b2d2f93be2a97e51997958ee694dafb16c6 Mon Sep 17 00:00:00 2001
From: Jan-Lukas Else <mail@jlelse.de>
Date: Tue, 28 Jul 2020 21:52:56 +0200
Subject: [PATCH] Graceful shutdown

---
 http.go | 21 ++++++++++++++++++++-
 main.go |  6 +++++-
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/http.go b/http.go
index 039a372..c03b77f 100644
--- a/http.go
+++ b/http.go
@@ -1,10 +1,15 @@
 package main
 
 import (
+	"context"
 	"github.com/labstack/echo/v4"
 	"github.com/labstack/echo/v4/middleware"
+	"log"
 	"net/http"
+	"os"
+	"os/signal"
 	"strconv"
+	"time"
 )
 
 func startServer() {
@@ -19,7 +24,21 @@ func startServer() {
 	e.GET("/*", servePost)
 
 	address := ":" + strconv.Itoa(appConfig.server.port)
-	e.Logger.Fatal(e.Start(address))
+	go func() {
+		if err := e.Start(address); err != nil {
+			log.Println("Shutting down the server")
+		}
+	}()
+
+	// Wait for interrupt signal to gracefully shutdown the server with a timeout of 10 seconds.
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, os.Interrupt)
+	<-quit
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+	if err := e.Shutdown(ctx); err != nil {
+		e.Logger.Fatal(err)
+	}
 }
 
 func hello(c echo.Context) error {
diff --git a/main.go b/main.go
index db2fcde..e7adfe6 100644
--- a/main.go
+++ b/main.go
@@ -15,7 +15,11 @@ func main() {
 		log.Fatal(err)
 	}
 	defer func() {
-		log.Fatal(closeDb())
+		log.Println("Close database")
+		err := closeDb()
+		if err != nil {
+			log.Fatal(err)
+		}
 	}()
 	log.Println("Loaded database")
 	log.Println("Start server")