python-dependency-injector/examples/miniapps/monitoring-daemon-asyncio/monitoringdaemon/dispatcher.py
Roman Mogylatov e56b72e411 Add prototype
2020-08-05 13:13:09 -04:00

68 lines
1.9 KiB
Python

"""Dispatcher module."""
import asyncio
import logging
import signal
import time
from typing import List
from .monitors import Monitor
logger = logging.getLogger(__name__)
class Dispatcher:
def __init__(self, monitors: List[Monitor]) -> None:
self._monitors = monitors
self._monitor_tasks: List[asyncio.Task] = [] # type: ignore
self._stopping = False
def run(self) -> None:
asyncio.run(self._do_work())
async def _do_work(self) -> None:
logger.info('Dispatcher is starting up')
for monitor in self._monitors:
self._monitor_tasks.append(asyncio.create_task(self._run_monitor(monitor)))
logger.info('Monitoring task has been started %s', monitor.full_name)
asyncio.get_event_loop().add_signal_handler(signal.SIGTERM, self._stop)
asyncio.get_event_loop().add_signal_handler(signal.SIGINT, self._stop)
await asyncio.gather(*self._monitor_tasks, return_exceptions=True)
self._stop()
def _stop(self) -> None:
if self._stopping:
return
self._stopping = True
logger.info('Dispatcher is shutting down')
for task, monitor in zip(self._monitor_tasks, self._monitors):
task.cancel()
logger.info('Monitoring task has been stopped %s', monitor.full_name)
logger.info('Dispatcher shutting down finished successfully')
@staticmethod
async def _run_monitor(monitor: Monitor) -> None:
def _until_next(last: float) -> float:
time_took = time.time() - last
return monitor.check_every - time_took
while True:
time_start = time.time()
try:
await monitor.check()
except asyncio.CancelledError:
break
except Exception:
monitor.logger.exception('Error running monitoring check')
await asyncio.sleep(_until_next(last=time_start))