REFACTOR: Optimized Catagory IDs INput Validation

cms/internal/services/db.go

@@ -35,6 +35,7 @@ type Video struct {
 type DBClient interface {
 	CreateVideo(ctx context.Context, v Video) (Video, error)
 	ListCategories(ctx context.Context) ([]Category, error)
+	ListCategoriesIDs(ctx context.Context) ([]int16, error)
 }
 
 type DBConcrete struct {
@@ -102,6 +103,24 @@ func (svc DBConcrete) ListCategories(ctx context.Context) ([]Category, error) {
 	return categories, rows.Err()
 }
 
+func (svc DBConcrete) ListCategoriesIDs(ctx context.Context) ([]int16, error) {
+	rows, err := svc.SQLDB.QueryContext(ctx, `SELECT id FROM categories`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var categories []int16
+	for rows.Next() {
+		var category int16
+		if err := rows.Scan(&category); err != nil {
+			return nil, err
+		}
+		categories = append(categories, category)
+	}
+	return categories, rows.Err()
+}
+
 func (svc DBConcrete) Migrate() {
 	if err := db.Migrate(svc.SQLDB); err != nil {
 		panic(err)