fix(api): prevent the creation of multiple admin users (#1251)

api/cmd/portainer/main.go

@@ -186,7 +186,6 @@ func main() {
 	applicationStatus := initStatus(authorizeEndpointMgmt, flags)
 
 	if *flags.Endpoint != "" {
-		var endpoints []portainer.Endpoint
 		endpoints, err := store.EndpointService.Endpoints()
 		if err != nil {
 			log.Fatal(err)
@@ -229,7 +228,12 @@ func main() {
 	}
 
 	if adminPasswordHash != "" {
+		users, err := store.UserService.UsersByRole(portainer.AdministratorRole)
+		if err != nil {
+			log.Fatal(err)
+		}
 
+		if len(users) == 0 {
 			log.Printf("Creating admin user with password hash %s", adminPasswordHash)
 			user := &portainer.User{
 				Username: "admin",
@@ -240,6 +244,9 @@ func main() {
 			if err != nil {
 				log.Fatal(err)
 			}
+		} else {
+			log.Println("Instance already has an administrator user defined. Skipping admin password related flags.")
+		}
 	}
 
 	var server portainer.Server = &http.Server{