on_custom_event() — langchain Function Reference

Architecture documentation for the on_custom_event() function in base.py from the langchain codebase.

Function python Observability TelemetryUtilities calls 1 called by 1

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Observability→ TelemetryUtilities→ on_custom_event() — langchain Function Reference

Dependency Diagram

graph TD
  68b4a253_3986_66d9_d689_539f5e1606fa["on_custom_event()"]
  64513429_d001_87b1_5f19_cc17a3f3577b["AsyncCallbackHandler"]
  68b4a253_3986_66d9_d689_539f5e1606fa -->|defined in| 64513429_d001_87b1_5f19_cc17a3f3577b
  1011b56d_ffc0_acdc_797f_fc9f30876158["on_custom_event()"]
  1011b56d_ffc0_acdc_797f_fc9f30876158 -->|calls| 68b4a253_3986_66d9_d689_539f5e1606fa
  1011b56d_ffc0_acdc_797f_fc9f30876158["on_custom_event()"]
  68b4a253_3986_66d9_d689_539f5e1606fa -->|calls| 1011b56d_ffc0_acdc_797f_fc9f30876158
  style 68b4a253_3986_66d9_d689_539f5e1606fa fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/core/langchain_core/callbacks/base.py lines 874–895

    async def on_custom_event(
        self,
        name: str,
        data: Any,
        *,
        run_id: UUID,
        tags: list[str] | None = None,
        metadata: dict[str, Any] | None = None,
        **kwargs: Any,
    ) -> None:
        """Override to define a handler for custom events.

        Args:
            name: The name of the custom event.
            data: The data for the custom event.

                Format will match the format specified by the user.
            run_id: The ID of the run.
            tags: The tags associated with the custom event (includes inherited tags).
            metadata: The metadata associated with the custom event (includes inherited
                metadata).
        """