Method _astream

libs/core/langchain_core/language_models/llms.py:581–623

An async version of the _stream method. The default implementation uses the synchronous _stream method and wraps it in an async iterator. Subclasses that need to provide a true async implementation should override this method. Args: prompt: The prompt to

(
        self,
        prompt: str,
        stop: Optional[List[str]] = None,
        run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
        **kwargs: Any,
    )

        raise NotImplementedError()

    async def _astream(
        self,
        prompt: str,
        stop: Optional[List[str]] = None,
        run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
        **kwargs: Any,
    ) -> AsyncIterator[GenerationChunk]:
        """An async version of the _stream method.

        The default implementation uses the synchronous _stream method and wraps it in
        an async iterator. Subclasses that need to provide a true async implementation
        should override this method.

        Args:
            prompt: The prompt to generate from.
            stop: Stop words to use when generating. Model output is cut off at the
                first occurrence of any of these substrings.
            run_manager: Callback manager for the run.
            **kwargs: Arbitrary additional keyword arguments. These are usually passed
                to the model provider API call.

        Returns:
            An async iterator of GenerationChunks.
        """
        iterator = await run_in_executor(
            None,
            self._stream,
            prompt,
            stop,
            run_manager.get_sync() if run_manager else None,
            **kwargs,
        )
        done = object()
        while True:
            item = await run_in_executor(
                None,
                next,
                iterator,
                done,  # type: ignore[call-arg, arg-type]
            )
            if item is done:
                break
            yield item  # type: ignore[misc]

    def generate_prompt(
        self,