feat: add support for multi filter retriever

[srini047]

Related Issues

• fixes Add a MultiFilterRetriever #10995

Proposed Changes:

Add support for MultiFilterRetriever, a new retriever component that executes multiple filter queries against a document store in parallel and returns a single, de-duplicated list of documents sorted by relevance score.

How did you test it?

Added unit tests around the new filter and ensured older doesn't break.

Notes for the reviewer

Checklist

• I have read the contributors guidelines and the code of conduct.
• I have updated the related issue with new insights and changes.
• I have added unit tests and updated the docstrings.
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test: and added ! in case the PR includes breaking changes.
• I have documented my code.
• I have added a release note file, following the contributors guidelines.
• I have run pre-commit hooks and fixed any issue.

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[bogdankostic]

Hi @srini047, thank you very much for the PR! I left a few comments on how we can simplify the MultiFilterRetriever.

[bogdankostic]

Thanks for addressing the requested changes @srini047!

Looking at the current implementation, since FilterRetriever is the only retriever that can be used with MultiFilterRetriever, I think we should simplify the API by accepting a document_store parameter directly instead of retriever. This way, MultiFilterRetriever can create the FilterRetriever internally and users get a simpler interface.

[srini047]

Thanks for addressing the requested changes @srini047!

Looking at the current implementation, since FilterRetriever is the only retriever that can be used with MultiFilterRetriever, I think we should simplify the API by accepting a document_store parameter directly instead of retriever. This way, MultiFilterRetriever can create the FilterRetriever internally and users get a simpler interface.

@bogdankostic If we look at the issue that was the ask to take filters as input: MultiFilterRetriever so a version of the FilterRetriever that can handle a list of filters as input.

WDYT?

[bogdankostic]

Sorry @srini047, I think I was not communicating precisely enough. What I'm suggesting does not affect the run method, it should still take a list of filters as input. I'm only suggesting to change the __init__ to accept a document_store directly instead of a FilterRetriever instance, since MultiFilterRetriever only ever uses FilterRetriever internally.

Here's a skeleton to illustrate what I mean:

@component
class MultiFilterRetriever:
    def __init__(self, document_store: DocumentStore, max_workers: int = 3) -> None:
        self.document_store = document_store
        self.max_workers = max_workers
        self._retriever = FilterRetriever(document_store=document_store)

    @component.output_types(documents=list[Document])
    def run(self, filters: list[dict[str, Any]]) -> dict[str, list[Document]]:
        ...

This way users don't need to create a FilterRetriever themselves, they just pass the document_store and MultiFilterRetriever handles the rest internally.

[srini047]

Sorry @srini047, I think I was not communicating precisely enough. What I'm suggesting does not affect the run method, it should still take a list of filters as input. I'm only suggesting to change the __init__ to accept a document_store directly instead of a FilterRetriever instance, since MultiFilterRetriever only ever uses FilterRetriever internally.

Here's a skeleton to illustrate what I mean:

@component
class MultiFilterRetriever:
    def __init__(self, document_store: DocumentStore, max_workers: int = 3) -> None:
        self.document_store = document_store
        self.max_workers = max_workers
        self._retriever = FilterRetriever(document_store=document_store)

    @component.output_types(documents=list[Document])
    def run(self, filters: list[dict[str, Any]]) -> dict[str, list[Document]]:
        ...

This way users don't need to create a FilterRetriever themselves, they just pass the document_store and MultiFilterRetriever handles the rest internally.

@bogdankostic Thanks for the clarification yes I get the crux and modified the code accordingly. This makes more sense now.

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Project	Deployment	Actions	Updated (UTC)
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[bogdankostic]

Thank you @srini047 :)