load_cassette() — langchain Function Reference

Architecture documentation for the load_cassette() function in conftest.py from the langchain codebase.

Function python LangChainCore Runnables calls 1

Entity Profile

LangChainCore→ Runnables→ load_cassette() — langchain Function Reference

Dependency Diagram

graph TD
  a2cc7573_d2be_e845_b5cb_67b28e1b0650["load_cassette()"]
  d3622376_b455_b9cd_a885_7c3b3f1e4e0a["CustomPersister"]
  a2cc7573_d2be_e845_b5cb_67b28e1b0650 -->|defined in| d3622376_b455_b9cd_a885_7c3b3f1e4e0a
  47260e6b_5b0f_a7b2_ddb7_5ff761d590a6["deserialize()"]
  a2cc7573_d2be_e845_b5cb_67b28e1b0650 -->|calls| 47260e6b_5b0f_a7b2_ddb7_5ff761d590a6
  style a2cc7573_d2be_e845_b5cb_67b28e1b0650 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/standard-tests/langchain_tests/conftest.py lines 59–73

    def load_cassette(
        cls,
        cassette_path: str | PathLike[str],
        serializer: CustomSerializer,
    ) -> tuple[list[Any], list[Any]]:
        """Load a cassette from a file."""
        # If cassette path is already Path this is a no-op
        cassette_path = Path(cassette_path)
        if not cassette_path.is_file():
            msg = f"Cassette file {cassette_path} does not exist."
            raise CassetteNotFoundError(msg)
        with cassette_path.open(mode="rb") as f:
            data = f.read()
        deser = serializer.deserialize(data)
        return deser["requests"], deser["responses"]