dify/api/agent-notes/services/dataset_service.py.md

Purpose

api/services/dataset_service.py hosts dataset/document service logic used by console and API controllers.

Batch document operations

• Batch document workflows should avoid N+1 database queries by using set-based lookups.
• Tenant checks must be enforced consistently across dataset/document operations.
• DocumentService.get_documents_by_ids(...) fetches documents for a dataset using id.in_(...).
• FileService.get_upload_files_by_ids(...) performs tenant-scoped batch lookup for UploadFile (dedupes ids with set(...)).
• DocumentService.get_document_download_url(...) and prepare_document_batch_download_zip(...) handle dataset/document permission checks plus Document -> UploadFile validation for download endpoints.

Verification plan

• Exercise document list and download endpoints that use the service helpers.
• Confirm batch download uses constant query count for documents + upload files.
• Request a ZIP with a missing document id and confirm a 404 is returned.