DocstoreExplorer Class — langchain Architecture

Architecture documentation for the DocstoreExplorer class in base.py from the langchain codebase.

Class python

Entity Profile

Dependency Diagram

graph TD
  a63b0fef_9f28_1339_c784_3f96b497636a["DocstoreExplorer"]
  935e1032_d88a_f226_7789_5aacc43bb0c8["Document"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|extends| 935e1032_d88a_f226_7789_5aacc43bb0c8
  9ccefa56_209b_c990_304c_d902563c789e["base.py"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|defined in| 9ccefa56_209b_c990_304c_d902563c789e
  00a7c695_d7b4_3d1a_123d_baa7e8c87927["__init__()"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|method| 00a7c695_d7b4_3d1a_123d_baa7e8c87927
  0302beb1_1ddf_3755_f461_54162de12e81["search()"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|method| 0302beb1_1ddf_3755_f461_54162de12e81
  02a2958f_7374_1f5e_0897_f932eb954395["lookup()"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|method| 02a2958f_7374_1f5e_0897_f932eb954395
  c3532df5_6e84_5467_2953_e60282892892["_summary()"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|method| c3532df5_6e84_5467_2953_e60282892892
  7d5a2bdc_a9ca_974a_8b22_ec1d405f35f4["_paragraphs()"]
  a63b0fef_9f28_1339_c784_3f96b497636a -->|method| 7d5a2bdc_a9ca_974a_8b22_ec1d405f35f4

Relationship Graph

Source Code

libs/langchain/langchain_classic/agents/react/base.py lines 89–135

class DocstoreExplorer:
    """Class to assist with exploration of a document store."""

    def __init__(self, docstore: Docstore):
        """Initialize with a docstore, and set initial document to None."""
        self.docstore = docstore
        self.document: Document | None = None
        self.lookup_str = ""
        self.lookup_index = 0

    def search(self, term: str) -> str:
        """Search for a term in the docstore, and if found save."""
        result = self.docstore.search(term)
        if isinstance(result, Document):
            self.document = result
            return self._summary
        self.document = None
        return result

    def lookup(self, term: str) -> str:
        """Lookup a term in document (if saved)."""
        if self.document is None:
            msg = "Cannot lookup without a successful search first"
            raise ValueError(msg)
        if term.lower() != self.lookup_str:
            self.lookup_str = term.lower()
            self.lookup_index = 0
        else:
            self.lookup_index += 1
        lookups = [p for p in self._paragraphs if self.lookup_str in p.lower()]
        if len(lookups) == 0:
            return "No Results"
        if self.lookup_index >= len(lookups):
            return "No More Results"
        result_prefix = f"(Result {self.lookup_index + 1}/{len(lookups)})"
        return f"{result_prefix} {lookups[self.lookup_index]}"

    @property
    def _summary(self) -> str:
        return self._paragraphs[0]

    @property
    def _paragraphs(self) -> list[str]:
        if self.document is None:
            msg = "Cannot get paragraphs without a document"
            raise ValueError(msg)
        return self.document.page_content.split("\n\n")