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Module docs2answers


class Docs2Answers(BaseComponent)

This Node is used to convert retrieved documents into predicted answers format. It is useful for situations where you are calling a Retriever only pipeline via REST API. This ensures that your output is in a compatible format.

Module join_docs


class JoinDocuments(BaseComponent)

A node to join documents outputted by multiple retriever nodes.

The node allows multiple join modes:

  • concatenate: combine the documents from multiple nodes. Any duplicate documents are discarded.
  • merge: merge scores of documents from multiple nodes. Optionally, each input score can be given a different weight & a top_k limit can be set. This mode can also be used for "reranking" retrieved documents.


| __init__(join_mode: str = "concatenate", weights: Optional[List[float]] = None, top_k_join: Optional[int] = None)


  • join_mode: concatenate to combine documents from multiple retrievers or merge to aggregate scores of individual documents.
  • weights: A node-wise list(length of list must be equal to the number of input nodes) of weights for adjusting document scores when using the merge join_mode. By default, equal weight is given to each retriever score. This param is not compatible with the concatenate join_mode.
  • top_k_join: Limit documents to top_k based on the resulting scores of the join.