postgres.go

// Package database opens the PostgreSQL connection pool and runs GORM
// AutoMigrate so developers can bootstrap quickly from an empty database.
//
// For production, prefer versioned SQL migrations (see /scripts) applied by
// your CI/CD pipeline; AutoMigrate is convenient but does not manage indexes
// renames or destructive changes as safely as explicit migrations.
package database

import (
	"fmt"
	"log"

	"baasid/internal/models"

	"gorm.io/driver/postgres"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

// Connect opens a GORM DB handle using the given PostgreSQL DSN.
//
// The DSN format is documented at https://www.postgresql.org/docs/current/libpq-connect.html#LIBPQ-CONNSTRING
// and accepted by the pgx driver underneath GORM's postgres dialector.
func Connect(dsn string) (*gorm.DB, error) {
	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
		// Logger prints SQL in development; switch to logger.Silent in prod.
		Logger: logger.Default.LogMode(logger.Info),
	})
	if err != nil {
		return nil, fmt.Errorf("gorm open: %w", err)
	}

	sqlDB, err := db.DB()
	if err != nil {
		return nil, fmt.Errorf("gorm sql.DB: %w", err)
	}

	// Reasonable defaults for a small REST service; tune for your load test.
	sqlDB.SetMaxIdleConns(5)
	sqlDB.SetMaxOpenConns(20)

	if err := db.AutoMigrate(&models.SystemUser{}, &models.Goods{}); err != nil {
		return nil, fmt.Errorf("auto migrate: %w", err)
	}

	log.Println("database: connected and AutoMigrate completed")
	return db, nil
}