Source code for traits_futures.asyncio.event_loop

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"""
IEventLoop implementation for the main-thread asyncio event loop.
"""
import asyncio

from traits_futures.asyncio.event_loop_helper import EventLoopHelper
from traits_futures.asyncio.pingee import Pingee
from traits_futures.i_event_loop import IEventLoop


@IEventLoop.register
class AsyncioEventLoop:
    """
    IEventLoop implementation for the main-thread asyncio event loop.
    """

    def __init__(self):
        self._event_loop = asyncio.get_event_loop()

    def pingee(self, on_ping):
        """
        Return a new pingee.

        Parameters
        ----------
        on_ping
            Zero-argument callable, called on the main thread (under a running
            event loop) as a result of each ping sent. The return value of the
            callable is ignored.

        Returns
        -------
        pingee : IPingee
        """
        return Pingee(on_ping=on_ping, event_loop=self._event_loop)

    def helper(self):
        """
        Return a new event loop helper.

        Returns
        -------
        event_loop_helper : IEventLoopHelper
        """
        return EventLoopHelper(event_loop=self._event_loop)