refactor: split main on func

main.go

@@ -11,23 +11,14 @@ import (
 	"github.com/miekg/dns"
 )
 
-const TTL = uint32(60 * 10) // seconds
-
-func main() {
-	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
-	defer stop()
-
-	log.Println("Creating publisher")
-	publisher, err := publisher.NewPublisher()
-	if err != nil {
-		log.Fatalf("Can't create publisher: %v", err)
-	}
+const TTL = uint32(60 * 10) // in seconds
 
+func formatCname(hostnameFqdn string, cnames []string) []string {
 	log.Println("Formating CNAMEs:")
-	cnames := os.Args[1:]
+
 	for i, cname := range cnames {
 		if !dns.IsFqdn(cname) {
-			cnames[i] = dns.Fqdn(cname + "." + publisher.Fqdn())
+			cnames[i] = dns.Fqdn(cname + "." + hostnameFqdn)
 
 			log.Printf("  > '%s' (added current FQDN)", cnames[i])
 			continue
@@ -36,17 +27,25 @@ func main() {
 		log.Printf("  > '%s'", cname)
 	}
 
+	return cnames
+}
+
+func publishing(ctx context.Context, publisher *publisher.Publisher, cnames []string) {
 	resendDuration := time.Duration(TTL/2) * time.Second
 	log.Printf("Publishing every %v and CNAME TTL=%ds.", resendDuration, TTL)
 
 	// To start publishing immediately
 	// https://github.com/golang/go/issues/17601
-	publisher.PublishCNAMES(os.Args[1:], TTL)
+	if err := publisher.PublishCNAMES(cnames, TTL); err != nil {
+		log.Fatalf("can't publish CNAMEs: %v", err)
+	}
 
 	for {
 		select {
 		case <-time.Tick(resendDuration):
-			publisher.PublishCNAMES(os.Args[1:], TTL)
+			if err := publisher.PublishCNAMES(cnames, TTL); err != nil {
+				log.Fatalf("can't publish CNAMEs: %v", err)
+			}
 		case <-ctx.Done():
 			log.Println("Closing publisher...")
 			if err := publisher.Close(); err != nil {
@@ -56,3 +55,17 @@ func main() {
 		}
 	}
 }
+
+func main() {
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
+	defer stop()
+
+	log.Println("Creating publisher")
+	publisher, err := publisher.NewPublisher()
+	if err != nil {
+		log.Fatalf("Can't create publisher: %v", err)
+	}
+
+	cnames := formatCname(publisher.Fqdn(), os.Args[1:])
+	publishing(ctx, publisher, cnames)
+}