feat(weaviate): add tenant support in write_documents with tests (syn…

[Akash504-ai]

Related Issues

• fixes Weaviate: Consider Adding support for multi tenancy #472

Proposed Changes

• Added tenant support to write_documents and write_documents_async
• Updated internal batch write logic to pass tenant parameter correctly
• Enables basic multi-tenancy support for Weaviate document store
• Added tests for tenant support in:
  • sync document store
  • async document store

How did you test it?

• Added integration tests for:
  • test_write_documents_with_tenant
  • test_write_documents_with_tenant_async
• Verified no regression in default (non-tenant) behavior
• Did not run full Weaviate integration locally, relying on CI for validation

Notes for the reviewer

• Changes are minimal and focused on tenant support in write operations
• Both sync and async flows are covered
• Backward compatible (no tenant → existing behavior unchanged)

Checklist

• I have read the contributors guidelines and code of conduct
• I have updated the related issue
• I added tests
• I used a conventional commit message

[CLAassistant]

All committers have signed the CLA.

[julian-risch]

Hello @Akash504-ai Thank you for opening this pull request. I have a couple of smaller change requests, which I explain in more detail below. Please keep comments that are not related to tenant_support unchanged in this pull request. Other than that the code changes look quite good to me already.

[julian-risch]

This test could check if _write_async get's called with the expected tenant parameter value.

[Akash504-ai]

Thanks for the suggestion! Initially I implemented the test using _write_async mocking, but it was not aligned with the current implementation and caused CI failures.
I updated the test to validate the actual behavior instead. Let me know if you'd prefer keeping the internal call assertion happy to adjust accordingly.

[julian-risch]

@Akash504-ai Thank you for iterating on this PR. Could you please also address my other change requests and restore comments that this PR removes in its current state? #3056 (review)
Comments that are not related to tenant_support should remain unchanged in this pull request please.

[github-actions]

Coverage report (weaviate)

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
integrations/weaviate/src/haystack_integrations/document_stores/weaviate
document_store.py					953-975, 985-1008, 1018-1033, 1045-1046, 1063, 1123-1126, 1159, 1297-1305, 1322-1341, 1365, 1381, 1389, 1402-1408, 1411-1412, 1476-1480
Project Total

This report was generated by python-coverage-comment-action

[Akash504-ai]

I've restored the unrelated comments/docstrings that were modified and addressed the remaining issues from the conflict resolution. All checks are now passing. Please let me know if there's anything else that should be adjusted.