statemachine.py

   1 from libtuer import ThreadFunction, logger, fire_and_forget, fire_and_forget_cmd
   2 from actor import Actor
   3 import os, random, time, threading
   4
   5 # logger.{debug,info,warning,error,critical}
   6
   7 def play_sound (what):
   8         try:
   9                 soundfiles = os.listdir(SOUNDS_DIRECTORY+what)
  10         except FileNotFoundError:
  11                 logger.error("StateMachine: Unable to list sound files in %s" % (SOUNDS_DIRECTORY+what))
  12                 return
  13         soundfile = SOUNDS_DIRECTORY + what + '/' + random.choice(soundfiles)
  14         fire_and_forget_cmd ([SOUNDS_PLAYER,soundfile], logger.error, "StateMachine: ")
  15
  16 # convert an absolute nervlist to a relative one
  17 def nervlist_abs2rel(nervlist_abs):
  18         nervlist_rel = []
  19         last_t = 0
  20         for (t, f) in nervlist_abs:
  21                 assert t >= last_t
  22                 nervlist_rel.append((t-last_t, f))
  23         return nervlist_rel
  24
  25
  26 # StateUnlocking constants
  27 OPEN_REPEAT_TIMEOUT = 7
  28 OPEN_REPEAT_NUMBER = 3
  29
  30 # StateLocking constants
  31 CLOSE_REPEAT_TIMEOUT = 7
  32 CLOSE_REPEAT_NUMBER = 3
  33
  34 # StateFallback constants
  35 FALLBACK_LEAVE_DELAY_LOCK = 5 # seconds
  36
  37 # StateAboutToOpen constants
  38 ABOUTOPEN_NERVLIST = nervlist_abs2rel([(5, lambda : play_sound("flipswitch")), (10, lambda:play_sound("flipswitch")),\
  39         (20, lambda:play_sound("flipswitch")), (30, lambda:play_sound("flipswitch")), (30, lambda:logger.error("Space open but switch not flipped for 30 seconds")),\
  40         (40, lambda:play_sound("flipswitch")), (50, lambda:play_sound("flipswitch")), (60, lambda:play_sound("flipswitch")),
  41         (60, lambda:logger.critical("Space open but switch not flipped for 60 seconds")), (120, lambda:play_sound("flipswitch")),
  42         (10*60, lambda:logger.critical("Space open but switch not flipped for 10 minutes")),
  43         (60*60, lambda:logger.critical("Space open but switch not flipped for one hour"))])
  44
  45 # Timeout we wait after the switch was switched to "Closed", until we assume nobody will open the door and we just lock it
  46 # ALso the time we wait after the door was opend, till we assume something went wrong and start nerving
  47 LEAVE_TIMEOUT = 20
  48
  49 # play_sound constants
  50 SOUNDS_DIRECTORY = "/opt/tuer/sounds/"
  51 SOUNDS_PLAYER = "/usr/bin/mplayer"
  52
  53
  54 class Nerver():
  55         # A little utility class used to run the nervlists. A nervlist is a list of (n, f) tuples where f() is run after n seconds.
  56         # If f returns something, that's also returned by nerv.
  57         def __init__(self, nervlist):
  58                 self.nervlist = list(nervlist)
  59                 self.last_event_time = time.time()
  60
  61         def nerv(self):
  62                 if len(self.nervlist):
  63                         (wait_time, f) = self.nervlist[0]
  64                         now = time.time()
  65                         time_gone = now-self.last_event_time
  66                         # check if the first element is to be triggered
  67                         if time_gone >= wait_time:
  68                                 self.nervlist = self.nervlist[1:] # "pop" the first element, but do not modify original list
  69                                 self.last_event_time = now
  70                                 return f()
  71
  72
  73 class StateMachine():
  74         # commands you can send
  75         CMD_PINS = 0
  76         CMD_BUZZ = 1
  77         CMD_UNLOCK = 2
  78         CMD_WAKEUP = 3
  79         CMD_LAST = 4
  80
  81         class State():
  82                 def __init__(self, state_machine, nervlist = None):
  83                         self.state_machine = state_machine
  84                         self._nerver = None if nervlist is None else Nerver(nervlist)
  85                 def handle_pins_event(self):
  86                         pass # one needn't implement this
  87                 def handle_buzz_event(self,arg): # this shouldn't be overwritten
  88                         self.actor().act(Actor.CMD_BUZZ)
  89                         arg("200 okay: buzz executed")
  90                 def handle_cmd_unlock_event(self,arg):
  91                         if arg is not None:
  92                                 arg("412 Precondition Failed: The current state (%s) cannot handle the UNLOCK command. Try again later." % self.__class__.__name__)
  93                 def handle_wakeup_event(self):
  94                         if self._nerver is not None:
  95                                 return self._nerver.nerv()
  96                 def on_leave(self):
  97                         pass
  98                 def pins(self):
  99                         return self.state_machine.pins
 100                 def old_pins(self):
 101                         return self.state_machine.old_pins
 102                 def actor(self):
 103                         return self.state_machine.actor
 104                 def api(self):
 105                         return self.state_machine.api
 106                 def handle_event(self,ev,arg): # don't override
 107                         if ev == StateMachine.CMD_PINS:
 108                                 return self.handle_pins_event()
 109                         elif ev == StateMachine.CMD_BUZZ:
 110                                 return self.handle_buzz_event(arg)
 111                         elif ev == StateMachine.CMD_UNLOCK:
 112                                 return self.handle_cmd_unlock_event(arg)
 113                         elif ev == StateMachine.CMD_WAKEUP:
 114                                 return self.handle_wakeup_event()
 115                         else:
 116                                 raise Exception("Unknown command number: %d" % ev)
 117
 118         class AbstractNonStartState(State):
 119                 def handle_pins_event(self):
 120                         if self.pins().door_locked != (not self.pins().space_active):
 121                                 self.actor().act(Actor.CMD_RED_ON)
 122                         else:
 123                                 self.actor().act(Actor.CMD_RED_OFF)
 124                         return super().handle_pins_event()
 125
 126         class AbstractLockedState(AbstractNonStartState):
 127                 '''A state with invariant "The space is locked", switching to StateAboutToOpen when the space becomes unlocked'''
 128                 def __init__(self, sm, nervlist = None):
 129                         super().__init__(sm, nervlist)
 130                         self.actor().act(Actor.CMD_GREEN_OFF)
 131                 def handle_pins_event(self):
 132                         if not self.pins().door_locked:
 133                                 logger.info("Door unlocked, space is about to open")
 134                                 return StateMachine.StateAboutToOpen(self.state_machine)
 135                         return super().handle_pins_event()
 136
 137         class AbstractUnlockedState(AbstractNonStartState):
 138                 '''A state with invariant "The space is unlocked", switching to StateZu when the space becomes locked'''
 139                 def __init__(self, sm, nervlist = None):
 140                         super().__init__(sm, nervlist)
 141                         self.actor().act(Actor.CMD_GREEN_ON)
 142                 def handle_pins_event(self):
 143                         if self.pins().door_locked:
 144                                 logger.info("Door locked, closing space")
 145                                 if self.pins().space_active:
 146                                         logger.warning("StateMachine: door manually locked, but space switch is still on - going to StateZu")
 147                                         play_sound("manual_lock")
 148                                 return StateMachine.StateZu(self.state_machine)
 149                         return super().handle_pins_event()
 150
 151         class StateStart(State):
 152                 def __init__(self, sm, nervlist = None, fallback=False):
 153                         super().__init__(sm, nervlist)
 154                         self.fallback = fallback
 155                 def handle_pins_event(self):
 156                         pins = self.pins()
 157                         if not (pins.door_locked is None or pins.door_closed is None or pins.space_active is None or pins.bell_ringing is None):
 158                                 if self.fallback:
 159                                         logger.info("Going to StateFallback because running in fallback mode")
 160                                         return StateMachine.StateFallback(self.state_machine)
 161                                 if pins.door_locked:
 162                                         logger.info("All sensors got a value, switching to a proper state: Space is closed")
 163                                         return StateMachine.StateZu(self.state_machine)
 164                                 else:
 165                                         logger.info("All sensors got a value, switching to a proper state: Space is (about to) open")
 166                                         return StateMachine.StateAboutToOpen(self.state_machine)
 167                         return super().handle_pins_event()
 168
 169         class StateFallback(State):
 170                 def __init__(self, sm, nervlist = None):
 171                         super().__init__(sm, nervlist)
 172                         self._red_state = False
 173                 def handle_pins_event(self):
 174                         pins = self.pins()
 175                         # buzz if open and bell rang
 176                         if pins.space_active and pins.bell_ringing and not self.old_pins().bell_ringing:
 177                                 logger.info("StateFallback: Space switch on and door bell rung => buzzing")
 178                                 self.actor().act(Actor.CMD_BUZZ)
 179                         # set green LED according to space switch
 180                         if pins.space_active:
 181                                 self.actor().act(Actor.CMD_GREEN_ON)
 182                         else:
 183                                 self.actor().act(Actor.CMD_GREEN_OFF)
 184                         # primitive leaving procedure if space switch turned off
 185                         if not pins.space_active and self.old_pins().space_active:
 186                                 def _close_after_time():
 187                                         time.sleep(FALLBACK_LEAVE_DELAY_LOCK)
 188                                         self.actor().act(Actor.CMD_LOCK)
 189                                 fire_and_forget(_close_after_time)
 190                         # not calling superclass because we want to stay in fallback mode
 191                 def handle_wakeup_event(self):
 192                         # blink red LED
 193                         if self._red_state:
 194                                 self.actor().act(Actor.CMD_RED_OFF)
 195                                 self._red_state = False
 196                         else:
 197                                 self.actor().act(Actor.CMD_RED_ON)
 198                                 self._red_state = True
 199                 def handle_cmd_unlock_event(self,arg):
 200                         if arg is not None:
 201                                 arg("298 Fallback Okay: Trying to unlock the door. The System is in fallback mode, success information is not available.")
 202                         self.actor().act(Actor.CMD_UNLOCK)
 203
 204         class StateZu(AbstractLockedState):
 205                 def handle_cmd_unlock_event(self,callback):
 206                         return StateMachine.StateUnlocking(self.state_machine, callback)
 207                 def handle_pins_event(self):
 208                         if not self.old_pins().space_active and self.pins().space_active: # first thing to check: edge detection
 209                                 logger.info("Space toggled to active while it was closed - unlocking the door")
 210                                 return StateMachine.StateUnlocking(self.state_machine)
 211                         return super().handle_pins_event()
 212
 213         class StateUnlocking(AbstractLockedState):
 214                 def __init__(self,sm,callback=None):
 215                         # construct a nervlist
 216                         nervlist = [(OPEN_REPEAT_TIMEOUT, lambda: self.actor().act(Actor.CMD_UNLOCK)) for t in range(OPEN_REPEAT_NUMBER)]
 217                         nervlist += [(OPEN_REPEAT_TIMEOUT, self.could_not_open)]
 218                         super().__init__(sm,nervlist)
 219                         self.callbacks = []
 220                         self.actor().act(Actor.CMD_UNLOCK)
 221                         # enqueue the callback
 222                         self.handle_cmd_unlock_event(callback)
 223                 def notify(self, s, lastMsg):
 224                         for cb in self.callbacks:
 225                                 cb(s, lastMsg)
 226                 def on_leave(self):
 227                         s = "200 okay: door unlocked" if not self.pins().door_locked else ("500 internal server error: Couldn't unlock door with %d tries à %f seconds" % (OPEN_REPEAT_NUMBER,OPEN_REPEAT_TIMEOUT))
 228                         self.notify(s, lastMsg=True)
 229                 def handle_cmd_unlock_event(self,callback):
 230                         if callback is not None:
 231                                 callback("202 processing: Trying to unlock the door", lastMsg=False)
 232                                 self.callbacks.append(callback)
 233                 def could_not_open(self):
 234                         logger.critical("StateMachine: Couldn't open door after %d tries. Going back to StateZu." % OPEN_REPEAT_NUMBER)
 235                         return StateMachine.StateZu(self.state_machine)
 236
 237         class AbstractStateWhereUnlockingIsRedundant(AbstractUnlockedState):
 238                 def handle_cmd_unlock_event(self, callback):
 239                         callback("299 redundant: Space seems to be already open. Still processing your request tough.")
 240                         logger.info("StateMachine: Received UNLOCK command in %s. This should not be necessary." % self.__class__.__name__)
 241                         self.actor().act(Actor.CMD_UNLOCK)
 242
 243         class StateAboutToOpen(AbstractStateWhereUnlockingIsRedundant):
 244                 def __init__(self, sm):
 245                         super().__init__(sm, ABOUTOPEN_NERVLIST)
 246                 def handle_pins_event(self):
 247                         pins = self.pins()
 248                         if pins.space_active:
 249                                 logger.info("Space activated, opening procedure completed")
 250                                 return StateMachine.StateAuf(self.state_machine)
 251                         return super().handle_pins_event()
 252
 253         class StateAuf(AbstractStateWhereUnlockingIsRedundant):
 254                 def __init__(self,sm):
 255                         nervlist = [(24*60*60, lambda: logger.critical("Space is now open for 24h. Is everything all right?"))]
 256                         super().__init__(sm, nervlist)
 257                         self.last_buzzed = None
 258                         self.api().set_state(True)
 259                 def handle_pins_event(self):
 260                         pins = self.pins()
 261                         if pins.bell_ringing and not self.old_pins().bell_ringing: # first thing to check: edge detection
 262                                 # someone just pressed the bell
 263                                 logger.info("StateMachine: buzzing because of bell ringing in StateAuf")
 264                                 self.actor().act(Actor.CMD_BUZZ)
 265                         if not pins.space_active:
 266                                 logger.info("StateMachine: space switch turned off - starting leaving procedure")
 267                                 return StateMachine.StateAboutToLeave(self.state_machine)
 268                         return super().handle_pins_event()
 269                 def on_leave(self):
 270                         self.api().set_state(False)
 271
 272         class StateLocking(AbstractUnlockedState):
 273                 def __init__(self,sm):
 274                         # construct a nervlist
 275                         nervlist = [(CLOSE_REPEAT_TIMEOUT, lambda: self.actor().act(Actor.CMD_LOCK)) for t in range(CLOSE_REPEAT_NUMBER)]
 276                         nervlist += [(CLOSE_REPEAT_TIMEOUT, self.could_not_close)]
 277                         super().__init__(sm, nervlist)
 278                         if self.pins().door_closed: # this should always be true, but just to be sure...
 279                                 self.actor().act(Actor.CMD_LOCK)
 280                 def handle_pins_event(self):
 281                         pins = self.pins()
 282                         if not pins.door_closed:
 283                                 # TODO play a sound? This shouldn't happen, door was opened while we are locking
 284                                 logger.warning("StateMachine: door manually opened during locking")
 285                                 return StateMachine.StateAboutToOpen(self.state_machine)
 286                         # TODO do anything here if the switch is activated now?
 287                         return super().handle_pins_event()
 288                 def handle_cmd_unlock_event(self,callback):
 289                         callback("409 conflict: The sphinx is currently trying to lock the door. Try again later.")
 290                 def could_not_close(self):
 291                         logger.critical("StateMachine: Couldn't close door after %d tries. Going back to StateAboutToOpen." % CLOSE_REPEAT_NUMBER)
 292                         return StateMachine.StateAboutToOpen(self.state_machine)
 293
 294         class StateAboutToLeave(AbstractUnlockedState):
 295                 def __init__(self, sm):
 296                         nervlist = [(LEAVE_TIMEOUT, lambda: StateMachine.StateLocking(self.state_machine))]
 297                         super().__init__(sm, nervlist)
 298                 def handle_pins_event(self):
 299                         if not self.pins().door_closed:
 300                                 return StateMachine.StateLeaving(self.state_machine)
 301                         if self.pins().space_active:
 302                                 logger.info("Space re-activated, cancelling leaving procedure")
 303                                 return StateMachine.StateAuf(self.state_machine)
 304                         return super().handle_pins_event()
 305
 306         class StateLeaving(AbstractUnlockedState):
 307                 def __init__(self, sm):
 308                         nervlist = [(LEAVE_TIMEOUT, lambda: StateMachine.StateAboutToOpen(self.state_machine))]
 309                         super().__init__(sm, nervlist)
 310                 def handle_pins_event(self):
 311                         if self.pins().door_closed:
 312                                 logger.info("The space was left, locking the door")
 313                                 return StateMachine.StateLocking(self.state_machine)
 314                         if self.pins().space_active:
 315                                 logger.info("Space re-activated, cancelling leaving procedure")
 316                                 return StateMachine.StateAuf(self.state_machine)
 317                         return super().handle_pins_event()
 318
 319         def __init__(self, actor, waker, api, fallback = False):
 320                 self.actor = actor
 321                 self.api = api
 322                 self.callback = ThreadFunction(self._callback, name="StateMachine")
 323                 self.current_state = StateMachine.StateStart(self, fallback=fallback)
 324                 self.pins = None
 325                 self.old_pins = None
 326                 waker.register(lambda: self.callback(StateMachine.CMD_WAKEUP), 1.0) # wake up every second
 327                 # initially, the space is closed
 328                 api.set_state(False)
 329
 330         def stop (self):
 331                 self.callback.stop()
 332
 333         def _callback(self, cmd, arg=None):
 334                 # update pins
 335                 if cmd == StateMachine.CMD_PINS:
 336                         self.pins = arg
 337                 # handle stuff
 338                 newstate = self.current_state.handle_event(cmd,arg) # returns None or an instance of the new state
 339                 self.old_pins = self.pins
 340                 while newstate is not None:
 341                         assert isinstance(newstate, StateMachine.State), "I should get a state"
 342                         self.current_state.on_leave()
 343                         logger.debug("StateMachine: Doing state transition %s -> %s" % (self.current_state.__class__.__name__, newstate.__class__.__name__))
 344                         self.current_state = newstate
 345                         newstate = self.current_state.handle_event(StateMachine.CMD_PINS, self.pins)