more boilerplate and dev environment

backend/database.go

@@ -20,8 +20,14 @@ func InitDB() (*sql.DB, error) {
 		password = "secret"
 	}
 
-	// Build the DSN. The host "db" matches the service name in docker-compose.yml.
-	dsn := fmt.Sprintf("oworganizer:%s@tcp(db:3306)/?parseTime=true", password)
+	host := os.Getenv("DB_HOST")
+	if host == "" {
+		// Default to the Docker Compose service name.
+		host = "db"
+	}
+
+	// Build the DSN. The default host "db" matches the service name in docker-compose.yml.
+	dsn := fmt.Sprintf("oworganizer:%s@tcp(%s:3306)/?parseTime=true", password, host)
 
 	db, err := sql.Open("mysql", dsn)
 	if err != nil {