Why this change is needed:
Two critical P0 security vulnerabilities were identified in CursorReview:
1. UnifiedLock silently allows unprotected execution when lock is None, creating
false security and potential race conditions in multi-process scenarios
2. PostgreSQL migration copies ALL workspace data during legacy table migration,
violating multi-tenant isolation and causing data leakage
How it solves it:
- UnifiedLock now raises RuntimeError when lock is None instead of WARNING
- Added workspace parameter to setup_table() for proper data isolation
- Migration queries now filter by workspace in both COUNT and SELECT operations
- Added clear error messages to help developers diagnose initialization issues
Impact:
- lightrag/kg/shared_storage.py: UnifiedLock raises exception on None lock
- lightrag/kg/postgres_impl.py: Added workspace filtering to migration logic
- tests/test_unified_lock_safety.py: 3 tests for lock safety
- tests/test_workspace_migration_isolation.py: 3 tests for workspace isolation
- tests/test_dimension_mismatch.py: Updated table names and mocks
- tests/test_postgres_migration.py: Updated mocks for workspace filtering
Testing:
- All 31 tests pass (16 migration + 4 safety + 3 lock + 3 workspace + 5 dimension)
- Backward compatible: existing code continues working unchanged
- Code style verified with ruff and pre-commit hooks
