Rewrite shutdown for authorizer

Author: Sergey Kibish

cmd/authorizer/main.go

@@ -2,8 +2,10 @@ package main
 
 import (
 	"log"
+	"net/http"
 	"os"
 	"os/signal"
+	"syscall"
 
 	"github.com/skibish/trashdiena/pkg/config"
 
@@ -25,22 +27,24 @@ func main() {
 
 	sc := slack.New(c.ClientID, c.ClientSecret, c.RedirectURL)
 	sg := storage.New(fbase)
-
 	a := api.New(sc, sg)
-	go func() {
-		log.Fatal(a.Start(c.APIPort))
-	}()
-
-	// handle all the gracefull shutdowns
-	sigs := make(chan os.Signal, 1)
-	signal.Notify(sigs, os.Interrupt)
 
-	select {
-	case <-sigs:
+	// shutdown gracefully
+	go func() {
+		sigs := make(chan os.Signal, 1)
+		signal.Notify(sigs, os.Interrupt, syscall.SIGTERM)
+		<-sigs
 		log.Println("Performing shutdown...")
-		if a != nil {
-			a.Shutdown()
+		if err := a.Shutdown(); err != nil {
+			log.Printf("Failed to shutdown server: %v", err)
 		}
-		log.Println("Exiting...")
+	}()
+
+	log.Printf("Authorizer is ready to listen on port: %s", c.APIPort)
+	if err := a.Start(c.APIPort); err != http.ErrServerClosed {
+		log.Printf("Server failed: %v", err)
+		os.Exit(1)
 	}
+
+	log.Println("Exiting...")
 }