langchain_core.runnables.config.ContextThreadPoolExecutor

class langchain_core.runnables.config.ContextThreadPoolExecutor(max_workers=None, thread_name_prefix='', initializer=None, initargs=())

ThreadPoolExecutor that copies the context to the child thread.

Initializes a new ThreadPoolExecutor instance.

Parameters

• max_workers – The maximum number of threads that can be used to execute the given calls.

• thread_name_prefix – An optional name prefix to give our threads.

• initializer – A callable used to initialize worker threads.

• initargs – A tuple of arguments to pass to the initializer.

Methods

__init__([max_workers, thread_name_prefix, ...])	Initializes a new ThreadPoolExecutor instance.
map(fn, *iterables[, timeout, chunksize])	Returns an iterator equivalent to map(fn, iter).
shutdown([wait, cancel_futures])	Clean-up the resources associated with the Executor.
submit(func, *args, **kwargs)	Submit a function to the executor.

__init__(max_workers=None, thread_name_prefix='', initializer=None, initargs=())

Initializes a new ThreadPoolExecutor instance.

Parameters

• max_workers – The maximum number of threads that can be used to execute the given calls.

• thread_name_prefix – An optional name prefix to give our threads.

• initializer – A callable used to initialize worker threads.

• initargs – A tuple of arguments to pass to the initializer.

map(fn: Callable[[...], T], *iterables: Iterable[Any], timeout: float | None = None, chunksize: int = 1) → Iterator[T]

Returns an iterator equivalent to map(fn, iter).

Parameters

• fn (Callable[[...], T]) – A callable that will take as many arguments as there are passed iterables.

• timeout (float | None) – The maximum number of seconds to wait. If None, then there is no limit on the wait time.

• chunksize (int) – The size of the chunks the iterable will be broken into before being passed to a child process. This argument is only used by ProcessPoolExecutor; it is ignored by ThreadPoolExecutor.

• iterables (Iterable[Any]) –

Returns

map(func, *iterables) but the calls may be evaluated out-of-order.

Return type

An iterator equivalent to

Raises

• TimeoutError – If the entire result iterator could not be generated before the given timeout.

• Exception – If fn(*args) raises for any values.

shutdown(wait=True, *, cancel_futures=False)

Clean-up the resources associated with the Executor.

It is safe to call this method several times. Otherwise, no other methods can be called after this one.

Parameters

• wait – If True then shutdown will not return until all running futures have finished executing and the resources used by the executor have been reclaimed.

• cancel_futures – If True then shutdown will cancel all pending futures. Futures that are completed or running will not be cancelled.

submit(func: ~typing.Callable[[~P], ~langchain_core.runnables.config.T], *args: ~typing.~P, **kwargs: ~typing.~P) → Future[T]

Submit a function to the executor.

Parameters

• func (Callable[..., T]) – The function to submit.

• *args (Any) – The positional arguments to the function.

• **kwargs (Any) – The keyword arguments to the function.

Returns

The future for the function.

Return type

Future[T]