waker.py

   1 from libtuer import ThreadRepeater
   2 from collections import namedtuple
   3
   4 SLEEP_TIME = 0.5
   5
   6 ToBeWoken = namedtuple('ToBeWoken','f period time_since_call one_shot')
   7
   8 class Waker():
   9         def __init__(self, sm):
  10                 self._sm = sm
  11                 self._t = ThreadRepeater(self._wake, SLEEP_TIME, name="Waker")
  12                 self._tobewokens = []
  13
  14         def register(f, time, one_shot = False):
  15                 '''Register a function which is called approximately every <time> seconds (or just once, if one_shot is True). f should return quickly, or it will delay the waker!'''
  16                 time = max(time//SLEEP_TIME, 1)
  17                 self._tobewokens.append(ToBeWoken(f, time, 0, one_shot))
  18
  19         def _wake(self):
  20                 delete = []
  21                 # run the functions we ought to run
  22                 for tobewoken, idx in zip(self._tobewokens, range(len(self._tobewokens))):
  23                         tobewoken.time_since_call += 1
  24                         if tobewoken.time_since_call >= tobewoken.period:
  25                                 tobewoken.f()
  26                                 tobewoken.time_since_call = 0
  27                                 if tobewoken.one_shot:
  28                                         delete.append(idx)
  29                 # delete what we have to delete - in reverse order so the indices stay valid!
  30                 delete.reverse()
  31                 for idx in delete:
  32                         del self._tobewokens[idx]
  33
  34         def stop(self):
  35                 self._t.stop()