[keith991001]

Important

1. Read CONTRIBUTING.md.
2. Associated issue: rewrite property to accept session: Session as parameter #40372 (claimed in this comment; scope note below).

Summary

Part of #40372, follow-up to #41721.

Removes five legacy @property accessors in api/models/dataset.py that reach for the global db.session internally — each a thin wrapper around an existing session-aware get_* twin with no remaining property reads (checked production receivers, serializer from_attributes reads — SegmentWithSummary and the hit-testing flow already use explicit session paths — helper-indirected dump_response sites, tests, and intra-model consumers):

• DocumentSegment.dataset → get_dataset(session=...)
• DocumentSegment.document → get_document(session=...)
• DocumentSegment.child_chunks → get_child_chunks(session=...)
• DocumentSegment.attachments → get_attachments(session=...)
• DatasetQuery.queries → get_queries(session=...)

Scope note: the claim originally included ExternalKnowledgeApis.dataset_bindings, but its own to_dict() still consumes the property (caught by type-check), putting it in the same to_dict-deep-water group as Document.segment_count/hit_count/dataset_process_rule from #41721. It is left untouched and unclaimed.

Tests

Updated the two container-integration tests that read segment.dataset / segment.document as properties to call the get_* twins with the test session. The twins keep their existing unit coverage (get_child_chunks / get_attachments are exercised via SegmentWithSummary tests), all passing.

Screenshots

N/A (backend-only refactor).

Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran make lint && make type-check (backend) and vp staged (frontend) to appease the lint gods

From Claude Code

[github-actions]

Pyrefly Type Coverage

Metric	Base	PR	Delta
Type coverage	62.98%	62.98%	-0.00%
Strict coverage	62.58%	62.58%	-0.00%
Typed symbols	44,456	44,452	-4
Untyped symbols	26,299	26,298	-1
Modules	3331	3331	0