PR #35700: fix(api): preserve dataset metadata filters

• Repository: langgenius/dify
• Author: princepal9120
• State: open | merged: False
• Link: https://github.com/langgenius/dify/pull/35700

Description (problem / solution / changelog)

Summary

Fixes #35666.

The Service API hit-testing/retrieve endpoints already pass retrieval_model into HitTestingService.retrieve, and that service already knows how to apply metadata_filtering_conditions when present. However, the request schema model for retrieval_model did not include metadata_filtering_conditions, so Pydantic validation/model dumping dropped the field before it reached the retrieval layer.

This adds metadata_filtering_conditions to the shared RetrievalModel schema and adds a service API regression test proving the filter survives request parsing and is forwarded to HitTestingService.retrieve.

Why this matters

Requests like this should filter by metadata:

{
  "query": "some query",
  "retrieval_model": {
    "search_method": "semantic_search",
    "reranking_enable": false,
    "top_k": 4,
    "score_threshold_enabled": false,
    "metadata_filtering_conditions": {
      "logical_operator": "and",
      "conditions": [
        {"name": "category", "comparison_operator": "is", "value": "finance"}
      ]
    }
  }
}

Before this change, the metadata filter was silently removed during payload validation.

Validation

• python3 -m py_compile api/services/entities/knowledge_entities/knowledge_entities.py api/tests/unit_tests/controllers/service_api/dataset/test_hit_testing.py
• git diff --check

I also attempted the focused pytest command:

• UV_CACHE_DIR=/tmp/uv-cache uv run --frozen pytest tests/unit_tests/controllers/service_api/dataset/test_hit_testing.py -q

but the local runner could not complete dependency setup because this workspace ran out of disk while uv was downloading/building Dify's full API dependency graph.

Changed files

• api/services/entities/knowledge_entities/knowledge_entities.py (modified, +2/-0)
• api/tests/unit_tests/controllers/service_api/dataset/test_hit_testing.py (modified, +56/-0)