feat(core): Update list folders endpoint to support filter excludeFolderIdAndDescendants (no-changelog) (#13880)

packages/@n8n/api-types/src/dto/folders/list-folder-query.dto.ts

@@ -29,6 +29,7 @@ export const filterSchema = z
 		parentFolderId: z.string().optional(),
 		name: z.string().optional(),
 		tags: z.array(z.string()).optional(),
+		excludeFolderIdAndDescendants: z.string().optional(),
 	})
 	.strict();
 

packages/cli/src/databases/repositories/folder.repository.ts

@@ -136,6 +136,13 @@ export class FolderRepository extends Repository<FolderWithWorkflowAndSubFolderC
 
 		this.applyBasicFilters(query, filter);
 		this.applyTagsFilter(query, Array.isArray(filter?.tags) ? filter.tags : undefined);
+
+		if (
+			filter?.excludeFolderIdAndDescendants &&
+			typeof filter.excludeFolderIdAndDescendants === 'string'
+		) {
+			this.applyExcludeFolderFilter(query, filter.excludeFolderIdAndDescendants);
+		}
 	}
 
 	private applyBasicFilters(
@@ -293,4 +300,38 @@ export class FolderRepository extends Repository<FolderWithWorkflowAndSubFolderC
 			},
 		);
 	}
+
+	private applyExcludeFolderFilter(
+		query: SelectQueryBuilder<FolderWithWorkflowAndSubFolderCount>,
+		excludeFolderIdAndDescendants: string,
+	): void {
+		// Exclude the specific folder by ID
+		query.andWhere('folder.id != :excludeFolderIdAndDescendants', {
+			excludeFolderIdAndDescendants,
+		});
+
+		// Use a WITH RECURSIVE CTE to find all child folders of the excluded folder
+		const baseQuery = this.createQueryBuilder('f')
+			.select('f.id', 'id')
+			.addSelect('f.parentFolderId', 'parentFolderId')
+			.where('f.id = :excludeFolderIdAndDescendants', { excludeFolderIdAndDescendants });
+
+		const recursiveQuery = this.createQueryBuilder('child')
+			.select('child.id', 'id')
+			.addSelect('child.parentFolderId', 'parentFolderId')
+			.innerJoin('folder_tree', 'parent', 'child.parentFolderId = parent.id');
+
+		const subQuery = this.createQueryBuilder()
+			.select('tree.id')
+			.addCommonTableExpression(
+				`${baseQuery.getQuery()} UNION ALL ${recursiveQuery.getQuery()}`,
+				'folder_tree',
+				{ recursive: true },
+			)
+			.from('folder_tree', 'tree')
+			.setParameters({ excludeFolderIdAndDescendants });
+
+		// Exclude all children of the specified folder
+		query.andWhere(`folder.id NOT IN (${subQuery.getQuery()})`);
+	}
 }

packages/cli/test/integration/folder/folder.controller.test.ts

@@ -1014,6 +1014,39 @@ describe('GET /projects/:projectId/folders', () => {
 		expect(response.body.data[0].name).toBe('Folder 3');
 	});
 
+	test('should filter folders by excludeFolderIdAndDescendants', async () => {
+		const folder1 = await createFolder(ownerProject, { name: 'folder level 1' });
+		await createFolder(ownerProject, {
+			name: 'folder level 1.1',
+			parentFolder: folder1,
+		});
+		const folder12 = await createFolder(ownerProject, {
+			name: 'folder level 1.2',
+			parentFolder: folder1,
+		});
+		await createFolder(ownerProject, {
+			name: 'folder level 1.2.1',
+			parentFolder: folder12,
+		});
+		const folder122 = await createFolder(ownerProject, {
+			name: 'folder level 1.2.2',
+			parentFolder: folder12,
+		});
+		await createFolder(ownerProject, {
+			name: 'folder level 1.2.2.1',
+			parentFolder: folder122,
+		});
+
+		const response = await authOwnerAgent
+			.get(`/projects/${ownerProject.id}/folders`)
+			.query({ filter: `{ "excludeFolderIdAndDescendants": "${folder122.id}" }` });
+
+		expect(response.body.data.length).toBe(4);
+		expect(response.body.data.map((f: any) => f.name).sort()).toEqual(
+			['folder level 1', 'folder level 1.1', 'folder level 1.2.1', 'folder level 1.2'].sort(),
+		);
+	});
+
 	test('should apply pagination with take parameter', async () => {
 		// Create folders with consistent timestamps
 		for (let i = 1; i <= 5; i++) {