Pausable coroutines

utils.py

# ...

def pausable(pause, resume_check=None, delay_start=None, delay_resume=None):
    def inner_wrapper(coro):
        @asyncio.coroutine
        def replacement_coro(*args, **kwargs):
            for x in coro(*args, **kwargs):
                try:
                    if delay_start is not None:
                        if asyncio.iscoroutinefunction(delay_start):
                            yield from delay_start()
                        else:
                            raise TypeError("delay_start must be a coroutine function")
                    yield x
                    yield from pause()
                # catch exceptions the regular discord.py user might not catch
                except (OSError,
                        HTTPException,
                        GatewayNotFound,
                        ConnectionClosed,
                        aiohttp.ClientError,
                        asyncio.TimeoutError,
                        websockets.InvalidHandshake,
                        websockets.WebSocketProtocolError) as e:
                    if any(resume_check() if resume_check is not None else False or
                            # clean disconnect
                            (isinstance(e, ConnectionClosed) and
                             e.code == 1000) or
                            # connection issue
                            not isinstance(e, ConnectionClosed)):
                        if delay_resume is not None:
                            yield from delay_resume()
                    else:
                        raise

        return replacement_coro
    return inner_wrapper