initial server implementation

pkg/database/db.go

@@ -0,0 +1,51 @@
+package database
+
+import (
+	"fmt"
+
+	"gorm.io/driver/postgres"
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+)
+
+func Migrate(db *gorm.DB) error {
+	if err := db.AutoMigrate(&User{}, &Role{}); err != nil {
+		return fmt.Errorf("auto-migrate: %w", err)
+	}
+
+	defaultRoles := []Role{
+		{Name: "superadmin"},
+		{Name: "admin"},
+		{Name: "editor"},
+		{Name: "author"},
+		{Name: "viewer"},
+	}
+
+	for _, r := range defaultRoles {
+		if err := db.FirstOrCreate(&r, Role{Name: r.Name}).Error; err != nil {
+			return fmt.Errorf("seed role %q: %w", r.Name, err)
+		}
+	}
+
+	return nil
+}
+
+func NewDB(driver, dsn string) (*gorm.DB, error) {
+	var dialector gorm.Dialector
+
+	switch driver {
+	case "sqlite":
+		dialector = sqlite.Open(dsn)
+	case "postgres":
+		dialector = postgres.Open(dsn)
+	default:
+		return nil, fmt.Errorf("unsupported database driver: %s", driver)
+	}
+
+	db, err := gorm.Open(dialector, &gorm.Config{})
+	if err != nil {
+		return nil, fmt.Errorf("failed to open database: %w", err)
+	}
+
+	return db, nil
+}