2b201369b4
When I wrote the documentation for `asyncio.to_thread()`, I mistakenly assumed that `return await loop.run_in_executor(...)` within an async def function would return a Future. In reality, it returns a coroutine. This likely won't affect typical usage of `asyncio.to_thread()`, but it's important for the documentation to be correct here. In general, we also tend to avoid returning futures from high-level APIs in asyncio.
26 lines
790 B
Python
26 lines
790 B
Python
"""High-level support for working with threads in asyncio"""
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import functools
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import contextvars
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from . import events
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__all__ = "to_thread",
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async def to_thread(func, /, *args, **kwargs):
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"""Asynchronously run function *func* in a separate thread.
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Any *args and **kwargs supplied for this function are directly passed
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to *func*. Also, the current :class:`contextvars.Context` is propogated,
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allowing context variables from the main thread to be accessed in the
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separate thread.
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Return a coroutine that can be awaited to get the eventual result of *func*.
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"""
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loop = events.get_running_loop()
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ctx = contextvars.copy_context()
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func_call = functools.partial(ctx.run, func, *args, **kwargs)
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return await loop.run_in_executor(None, func_call)
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