Community: RankLLMRerank AttributeError (Handle list-based rerank results)

[b8zhong]

community: Fix AttributeError in RankLLMRerank (list object has no attribute candidates)

Description

This PR fixes an issue in RankLLMRerank where reranking fails with the following error:

AttributeError: 'list' object has no attribute 'candidates'

The issue arises because rerank_batch() returns a List[Result] instead of an object containing .candidates.

Changes Introduced

• Adjusted compress_documents() to support both:
  • Old API format: rerank_results.candidates
  • New API format: rerank_results as a list
  • Also fix wrong .txt location parsing while I was at it.

---

Issue

Fixes AttributeError in RankLLMRerank when using compression_retriever.invoke(). The issue is observed when rerank_batch() returns a list instead of an object with .candidates.

Relevant log:

AttributeError: 'list' object has no attribute 'candidates'

Dependencies

• No additional dependencies introduced.

---

Checklist

• Backward compatible with previous API versions
• Tested locally with different RankLLM models
• No new dependencies introduced
• Linted with make format && make lint
• Ready for review

---

Testing

• Ran compression_retriever.invoke(query)

Reviewers

If no review within a few days, please @mention one of:

• @baskaryan
• @efriis
• @eyurtsev
• @ccurme
• @vbarda
• @hwchase17

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[b8zhong]

Also gonna go ahead and update

text-embedding-ada-002 => text-embedding-3-large

And

gpt-3.5-turbo => gpt-4o-mini

For deprecation purposes. And, there was output changes so added that for consistency

[b8zhong]

@ccurme Hey! Would you happen to mind taking a look? Thanks in advance :)