services/nodemanager/arvnodeman/timedcallback.py

   1 #!/usr/bin/env python
   2
   3 from __future__ import absolute_import, print_function
   4
   5 import heapq
   6 import time
   7
   8 import pykka
   9
  10 from .config import actor_class
  11
  12 class TimedCallBackActor(actor_class):
  13     """Send messages to other actors on a schedule.
  14
  15     Other actors can call the schedule() method to schedule delivery of a
  16     message at a later time.  This actor runs the necessary event loop for
  17     delivery.
  18     """
  19     def __init__(self, max_sleep=1):
  20         super(TimedCallBackActor, self).__init__()
  21         self._proxy = self.actor_ref.proxy()
  22         self.messages = []
  23         self.max_sleep = max_sleep
  24
  25     def schedule(self, delivery_time, receiver, *args, **kwargs):
  26         if not self.messages:
  27             self._proxy.deliver()
  28         heapq.heappush(self.messages, (delivery_time, receiver, args, kwargs))
  29
  30     def deliver(self):
  31         if not self.messages:
  32             return None
  33         til_next = self.messages[0][0] - time.time()
  34         if til_next < 0:
  35             t, receiver, args, kwargs = heapq.heappop(self.messages)
  36             try:
  37                 receiver(*args, **kwargs)
  38             except pykka.ActorDeadError:
  39                 pass
  40         else:
  41             time.sleep(min(til_next, self.max_sleep))
  42         self._proxy.deliver()