feat(F-120): completed feature

project/migrations/041_category_delete_cascade.js

@@ -0,0 +1,48 @@
+/**
+ * F-120: Allow deleting a category by cascading to its children and the
+ * product-category links that point at it.
+ *
+ * - catalog_product_categories.category_id: ON DELETE CASCADE — when a product
+ *   loses all its categories it is fine; the product itself stays active.
+ * - categories_categories.parent_id: ON DELETE CASCADE — child categories are
+ *   removed along with their parent so admins can prune a branch in one go.
+ *
+ * @param {import('node-pg-migrate').MigrationBuilder} pgm
+ */
+export const up = (pgm) => {
+  pgm.sql(
+    'ALTER TABLE catalog_product_categories DROP CONSTRAINT IF EXISTS catalog_product_categories_category_id_fkey',
+  );
+  pgm.sql(
+    `ALTER TABLE catalog_product_categories
+       ADD CONSTRAINT catalog_product_categories_category_id_fkey
+       FOREIGN KEY (category_id) REFERENCES categories_categories(id) ON DELETE CASCADE`,
+  );
+  pgm.sql(
+    'ALTER TABLE categories_categories DROP CONSTRAINT IF EXISTS categories_categories_parent_id_fkey',
+  );
+  pgm.sql(
+    `ALTER TABLE categories_categories
+       ADD CONSTRAINT categories_categories_parent_id_fkey
+       FOREIGN KEY (parent_id) REFERENCES categories_categories(id) ON DELETE CASCADE`,
+  );
+};
+
+export const down = (pgm) => {
+  pgm.sql(
+    'ALTER TABLE catalog_product_categories DROP CONSTRAINT IF EXISTS catalog_product_categories_category_id_fkey',
+  );
+  pgm.sql(
+    `ALTER TABLE catalog_product_categories
+       ADD CONSTRAINT catalog_product_categories_category_id_fkey
+       FOREIGN KEY (category_id) REFERENCES categories_categories(id) ON DELETE RESTRICT`,
+  );
+  pgm.sql(
+    'ALTER TABLE categories_categories DROP CONSTRAINT IF EXISTS categories_categories_parent_id_fkey',
+  );
+  pgm.sql(
+    `ALTER TABLE categories_categories
+       ADD CONSTRAINT categories_categories_parent_id_fkey
+       FOREIGN KEY (parent_id) REFERENCES categories_categories(id) ON DELETE RESTRICT`,
+  );
+};

project/src/modules/categories/api/categories.routes.ts

@@ -155,9 +155,7 @@ export async function registerCategoriesRoutes(
     if (result === 'not_found') {
       throw new AppError(404, 'NOT_FOUND', 'Category not found');
     }
-    if (result === 'has_children') {
-      throw new AppError(409, 'CATEGORY_HAS_CHILDREN', 'Category has child categories');
-    }
+    // Children and product-category links cascade at the DB level (F-120).
     return reply.code(204).send();
   });
 

project/src/modules/categories/application/category-use-cases.ts

@@ -75,19 +75,22 @@ export class UpdateCategory {
   }
 }
 
-export type DeleteCategoryResult = 'deleted' | 'not_found' | 'has_children';
+export type DeleteCategoryResult = 'deleted' | 'not_found';
 
 export class DeleteCategory {
   constructor(private readonly categories: CategoryRepository) {}
 
+  /**
+   * Deletes the category and lets the database cascade to children and
+   * product-category links (F-120). Returns:
+   *  - 'not_found' if the id does not exist;
+   *  - 'deleted' on success.
+   */
   async execute(id: string): Promise<DeleteCategoryResult> {
     const category = await this.categories.findById(id);
     if (!category) {
       return 'not_found';
     }
-    if (await this.categories.hasChildren(id)) {
-      return 'has_children';
-    }
     return (await this.categories.delete(id)) ? 'deleted' : 'not_found';
   }
 }