##// END OF EJS Templates
removal deprecated in 7.10 (#14614)
removal deprecated in 7.10 (#14614)

File last commit:

r28782:9b49aad9
r29017:602590b8 merge
Show More
asyncio.py
63 lines | 1.8 KiB | text/x-python | PythonLexer
Jonathan Slenders
Add asyncio input hook for event loop integration.
r25277 """
Inputhook for running the original asyncio event loop while we're waiting for
input.
By default, in IPython, we run the prompt with a different asyncio event loop,
because otherwise we risk that people are freezing the prompt by scheduling bad
coroutines. E.g., a coroutine that does a while/true and never yield back
control to the loop. We can't cancel that.
However, sometimes we want the asyncio loop to keep running while waiting for
a prompt.
The following example will print the numbers from 1 to 10 above the prompt,
while we are waiting for input. (This works also because we use
prompt_toolkit`s `patch_stdout`)::
In [1]: import asyncio
In [2]: %gui asyncio
In [3]: async def f():
...: for i in range(10):
...: await asyncio.sleep(1)
...: print(i)
In [4]: asyncio.ensure_future(f())
"""
M Bussonnier
Reformat files that woudl only touch a single line.
r28782
Jonathan Slenders
Don't nest asyncio input hooks....
r25308 from prompt_toolkit import __version__ as ptk_version
Min RK
avoid deprecated get_event_loop...
r27387 from IPython.core.async_helpers import get_asyncio_loop
Jonathan Slenders
Don't nest asyncio input hooks....
r25308
Matthias Bussonnier
Run black on all files that would lead to 3 lines changes or less
r27843 PTK3 = ptk_version.startswith("3.")
Jonathan Slenders
Add asyncio input hook for event loop integration.
r25277
def inputhook(context):
Jonathan Slenders
Don't nest asyncio input hooks....
r25308 """
Inputhook for asyncio event loop integration.
"""
# For prompt_toolkit 3.0, this input hook literally doesn't do anything.
# The event loop integration here is implemented in `interactiveshell.py`
# by running the prompt itself in the current asyncio loop. The main reason
# for this is that nesting asyncio event loops is unreliable.
if PTK3:
return
# For prompt_toolkit 2.0, we can run the current asyncio event loop,
# because prompt_toolkit 2.0 uses a different event loop internally.
Min RK
avoid deprecated get_event_loop...
r27387 # get the persistent asyncio event loop
loop = get_asyncio_loop()
Jonathan Slenders
Add asyncio input hook for event loop integration.
r25277 def stop():
loop.stop()
Jonathan Slenders
Improve cleanup of asyncio input hook.
r25286 fileno = context.fileno()
loop.add_reader(fileno, stop)
try:
loop.run_forever()
finally:
loop.remove_reader(fileno)