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, datetime
   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         hour = datetime.datetime.time(datetime.datetime.now()).hour
  15         volume = 60 if hour >= 22 or hour <= 6 else 90
  16         fire_and_forget_cmd ([SOUNDS_PLAYER, "-volume", str(volume), soundfile], "StateMachine: ")
  17
  18 # convert an absolute nervlist to a relative one
  19 def nervlist_abs2rel(nervlist_abs):
  20         nervlist_rel = []
  21         last_t = 0
  22         for (t, f) in nervlist_abs:
  23                 assert t >= last_t
  24                 nervlist_rel.append((t-last_t, f))
  25                 last_t = t
  26         return nervlist_rel
  27
  28 # StateAuf constants
  29 HELLO_PROBABILITY = 0.2
  30
  31 # StateUnlocking constants
  32 OPEN_REPEAT_TIMEOUT = 7
  33 OPEN_REPEAT_NUMBER = 3
  34
  35 # StateLocking constants
  36 CLOSE_REPEAT_TIMEOUT = 7
  37 CLOSE_REPEAT_NUMBER = 3
  38
  39 # StateFallback constants
  40 FALLBACK_LEAVE_DELAY_LOCK = 5 # seconds
  41
  42 # StateAboutToOpen constants
  43 SWITCH_PRAISE_PROBABILITY = 0.5
  44 ABOUTOPEN_NERVLIST = nervlist_abs2rel([(10, lambda:play_sound("flipswitch")),\
  45         (20, lambda:play_sound("flipswitch")), (30, lambda:play_sound("flipswitch")), (30, lambda:logger.error("Space open but switch not flipped for 30 seconds")),\
  46         (40, lambda:play_sound("flipswitch")), (50, lambda:play_sound("flipswitch")), (60, lambda:play_sound("mail_sent")),
  47         (60, lambda:logger.critical("Space open but switch not flipped for 60 seconds")), (120, lambda:play_sound("mail_sent")),
  48         (10*60, lambda:logger.critical("Space open but switch not flipped for 10 minutes")),
  49         (60*60, lambda:logger.critical("Space open but switch not flipped for one hour"))])
  50
  51 # Timeout we wait after the switch was switched to "Closed", until we assume nobody will open the door and we just lock it
  52 # ALso the time we wait after the door was opend, till we assume something went wrong and start nerving
  53 LEAVE_TIMEOUT = 20
  54
  55 # play_sound constants
  56 SOUNDS_DIRECTORY = "/opt/tuer/sounds/"
  57 SOUNDS_PLAYER = "/usr/bin/mplayer"
  58
  59
  60 class Nerver():
  61         # 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.
  62         # If f returns something, that's also returned by nerv.
  63         def __init__(self, nervlist):
  64                 self.nervlist = list(nervlist)
  65                 self.last_event_time = time.time()
  66
  67         def nerv(self):
  68                 if len(self.nervlist):
  69                         (wait_time, f) = self.nervlist[0]
  70                         now = time.time()
  71                         time_gone = now-self.last_event_time
  72                         # check if the first element is to be triggered
  73                         if time_gone >= wait_time:
  74                                 self.nervlist = self.nervlist[1:] # "pop" the first element, but do not modify original list
  75                                 self.last_event_time = now
  76                                 return f()
  77
  78
  79 class StateMachine():
  80         # commands you can send
  81         CMD_PINS = 0
  82         CMD_BUZZ = 1
  83         CMD_UNLOCK = 2
  84         CMD_WAKEUP = 3
  85         CMD_LAST = 4
  86         CMD_LOCK = 5
  87         CMD_FALLBACK_ON = 6
  88         CMD_FALLBACK_OFF = 7
  89         CMD_STATUS = 8
  90
  91         class State():
  92                 def __init__(self, state_machine, nervlist = None):
  93                         self.state_machine = state_machine
  94                         self._nerver = None if nervlist is None else Nerver(nervlist)
  95                 def handle_pins_event(self):
  96                         pass # one needn't implement this
  97                 def handle_buzz_event(self,arg): # this shouldn't be overwritten
  98                         # Buzz twice to give users more time to run ;-)
  99                         self.actor().act(Actor.CMD_BUZZ)
 100                         self.actor().act(Actor.CMD_BUZZ)
 101                         arg("200 okay: buzz executed")
 102                 def handle_cmd_unlock_event(self,arg):
 103                         if arg is not None:
 104                                 arg("412 Precondition Failed: The current state (%s) cannot handle the UNLOCK command. Try again later." % self.__class__.__name__)
 105                 def handle_wakeup_event(self):
 106                         if self._nerver is not None:
 107                                 return self._nerver.nerv()
 108                 def handle_cmd_lock_event(self,arg):
 109                         arg("412 Precondition Failed: If not in fallback mode, use the hardware switch to lock the space.")
 110                 def handle_cmd_fallback_on_event(self,arg):
 111                         arg("200 okay: Entering fallback mode and notifying admins.")
 112                         logger.critical("Entering fallback mode. Somebody thinks, the hardware sensors are broken.")
 113                         return StateMachine.StateFallback(self.state_machine)
 114                 def handle_cmd_fallback_off_event(self,arg):
 115                         arg("412 Precondition Failed: Not in fallback mode!")
 116                 def handle_cmd_status_event(self,arg):
 117                         # TODO use a proper JSON lib
 118                         arg('200 okay: {state:\"%s\"}' % self.__class__.__name__)
 119                 def on_leave(self):
 120                         pass
 121                 def pins(self):
 122                         return self.state_machine.pins
 123                 def old_pins(self):
 124                         return self.state_machine.old_pins
 125                 def actor(self):
 126                         return self.state_machine.actor
 127                 def api(self):
 128                         return self.state_machine.api
 129                 def handle_event(self,ev,arg): # don't override
 130                         if ev == StateMachine.CMD_PINS:
 131                                 return self.handle_pins_event()
 132                         elif ev == StateMachine.CMD_BUZZ:
 133                                 return self.handle_buzz_event(arg)
 134                         elif ev == StateMachine.CMD_UNLOCK:
 135                                 return self.handle_cmd_unlock_event(arg)
 136                         elif ev == StateMachine.CMD_WAKEUP:
 137                                 return self.handle_wakeup_event()
 138                         elif ev == StateMachine.CMD_LOCK:
 139                                 return self.handle_cmd_lock_event(arg)
 140                         elif ev == StateMachine.CMD_FALLBACK_ON:
 141                                 return self.handle_cmd_fallback_on_event(arg)
 142                         elif ev == StateMachine.CMD_FALLBACK_OFF:
 143                                 return self.handle_cmd_fallback_off_event(arg)
 144                         elif ev == StateMachine.CMD_STATUS:
 145                                 return self.handle_cmd_status_event(arg)
 146                         else:
 147                                 raise Exception("Unknown command number: %d" % ev)
 148
 149         class AbstractNonStartState(State):
 150                 def handle_pins_event(self):
 151                         if self.pins().door_locked != (not self.pins().space_active):
 152                                 self.actor().act(Actor.CMD_RED_ON)
 153                         else:
 154                                 self.actor().act(Actor.CMD_RED_OFF)
 155                         return super().handle_pins_event()
 156
 157         class AbstractLockedState(AbstractNonStartState):
 158                 '''A state with invariant "The space is locked", switching to StateAboutToOpen when the space becomes unlocked'''
 159                 def __init__(self, sm, nervlist = None):
 160                         super().__init__(sm, nervlist)
 161                         self.actor().act(Actor.CMD_GREEN_OFF)
 162                 def handle_pins_event(self):
 163                         if not self.pins().door_locked:
 164                                 logger.info("Door unlocked, space is about to open")
 165                                 return StateMachine.StateAboutToOpen(self.state_machine)
 166                         return super().handle_pins_event()
 167
 168         class AbstractUnlockedState(AbstractNonStartState):
 169                 '''A state with invariant "The space is unlocked", switching to StateZu when the space becomes locked'''
 170                 def __init__(self, sm, nervlist = None):
 171                         super().__init__(sm, nervlist)
 172                         self.actor().act(Actor.CMD_GREEN_ON)
 173                 def handle_pins_event(self):
 174                         if self.pins().door_locked:
 175                                 logger.info("Door locked, closing space")
 176                                 if self.pins().space_active:
 177                                         logger.warning("StateMachine: door manually locked, but space switch is still on - going to StateZu")
 178                                         play_sound("manual_lock")
 179                                 return StateMachine.StateZu(self.state_machine)
 180                         return super().handle_pins_event()
 181
 182         class StateStart(State):
 183                 def __init__(self, sm, nervlist = None, fallback=False):
 184                         super().__init__(sm, nervlist)
 185                         self.fallback = fallback
 186                 def handle_pins_event(self):
 187                         pins = self.pins()
 188                         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):
 189                                 if self.fallback:
 190                                         logger.info("Going to StateFallback because running in fallback mode")
 191                                         return StateMachine.StateFallback(self.state_machine)
 192                                 if pins.door_locked:
 193                                         logger.info("All sensors got a value, switching to a proper state: Space is closed")
 194                                         return StateMachine.StateZu(self.state_machine)
 195                                 else:
 196                                         logger.info("All sensors got a value, switching to a proper state: Space is (about to) open")
 197                                         return StateMachine.StateAboutToOpen(self.state_machine)
 198                         return super().handle_pins_event()
 199
 200         class StateFallback(State):
 201                 def __init__(self, sm, nervlist = None):
 202                         super().__init__(sm, nervlist)
 203                         self._red_state = False
 204                 def handle_pins_event(self):
 205                         pins = self.pins()
 206                         # set green LED according to space switch
 207                         if pins.space_active:
 208                                 self.actor().act(Actor.CMD_GREEN_ON)
 209                         else:
 210                                 self.actor().act(Actor.CMD_GREEN_OFF)
 211                         # primitive leaving procedure if space switch turned off
 212                         if not pins.space_active and self.old_pins().space_active:
 213                                 def _close_after_time():
 214                                         time.sleep(FALLBACK_LEAVE_DELAY_LOCK)
 215                                         self.actor().act(Actor.CMD_LOCK)
 216                                 fire_and_forget(_close_after_time)
 217                         # not calling superclass because we want to stay in fallback mode
 218                 def handle_wakeup_event(self):
 219                         # blink red LED
 220                         if self._red_state:
 221                                 self.actor().act(Actor.CMD_RED_OFF)
 222                                 self._red_state = False
 223                         else:
 224                                 self.actor().act(Actor.CMD_RED_ON)
 225                                 self._red_state = True
 226                 def handle_cmd_unlock_event(self,arg):
 227                         if arg is not None:
 228                                 arg("200 okay: Trying to unlock the door. The System is in fallback mode, success information is not available.")
 229                         self.actor().act(Actor.CMD_UNLOCK)
 230                 def handle_cmd_lock_event(self,arg):
 231                         if arg is not None:
 232                                 arg("200 okay: Trying to lock the door. The System is in fallback mode, success information is not available.")
 233                         self.actor().act(Actor.CMD_LOCK)
 234                 def handle_cmd_fallback_on_event(self,arg):
 235                         arg("412 Precondition Failed: Fallback mode already active.")
 236                 def handle_cmd_fallback_off_event(self,arg):
 237                         arg("200 okay: Leaving fallback mode and notifying admins.")
 238                         logger.critical("Leaving fallback mode. Somebody thinks, the sensors are working again.")
 239                         return StateMachine.StateStart(self.state_machine)
 240
 241         class StateZu(AbstractLockedState):
 242                 def handle_cmd_unlock_event(self,callback):
 243                         return StateMachine.StateUnlocking(self.state_machine, callback)
 244                 def handle_pins_event(self):
 245                         if not self.old_pins().space_active and self.pins().space_active: # first thing to check: edge detection
 246                                 logger.info("Space toggled to active while it was closed - unlocking the door")
 247                                 return StateMachine.StateUnlocking(self.state_machine)
 248                         return super().handle_pins_event()
 249
 250         class StateUnlocking(AbstractLockedState):
 251                 def __init__(self,sm,callback=None):
 252                         # construct a nervlist
 253                         nervlist = [(OPEN_REPEAT_TIMEOUT, lambda: self.actor().act(Actor.CMD_UNLOCK)) for t in range(OPEN_REPEAT_NUMBER)]
 254                         nervlist += [(OPEN_REPEAT_TIMEOUT, self.could_not_open)]
 255                         super().__init__(sm,nervlist)
 256                         self.callbacks = []
 257                         self.actor().act(Actor.CMD_UNLOCK)
 258                         # enqueue the callback
 259                         self.handle_cmd_unlock_event(callback)
 260                 def notify(self, s, lastMsg):
 261                         for cb in self.callbacks:
 262                                 cb(s, lastMsg)
 263                 def on_leave(self):
 264                         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))
 265                         self.notify(s, lastMsg=True)
 266                 def handle_cmd_unlock_event(self,callback):
 267                         if callback is not None:
 268                                 callback("202 processing: Trying to unlock the door", lastMsg=False)
 269                                 self.callbacks.append(callback)
 270                 def could_not_open(self):
 271                         logger.critical("StateMachine: Couldn't open door after %d tries. Going back to StateZu." % OPEN_REPEAT_NUMBER)
 272                         return StateMachine.StateZu(self.state_machine)
 273
 274         class AbstractStateWhereUnlockingIsRedundant(AbstractUnlockedState):
 275                 def handle_cmd_unlock_event(self, callback):
 276                         callback("299 redundant: Space seems to be already open. Still processing your request tough.")
 277                         logger.info("StateMachine: Received UNLOCK command in %s. This should not be necessary." % self.__class__.__name__)
 278                         self.actor().act(Actor.CMD_UNLOCK)
 279
 280         class StateAboutToOpen(AbstractStateWhereUnlockingIsRedundant):
 281                 def __init__(self, sm):
 282                         super().__init__(sm, ABOUTOPEN_NERVLIST)
 283                 def handle_pins_event(self):
 284                         pins = self.pins()
 285                         if pins.space_active:
 286                                 logger.info("Space activated, opening procedure completed")
 287                                 if not self.old_pins().space_active and random.random() <= SWITCH_PRAISE_PROBABILITY:
 288                                         play_sound("success")
 289                                 return StateMachine.StateAuf(self.state_machine)
 290                         return super().handle_pins_event()
 291
 292         class StateAuf(AbstractStateWhereUnlockingIsRedundant):
 293                 def __init__(self,sm):
 294                         nervlist = [(24*60*60, lambda: logger.critical("Space is now open for 24h. Is everything all right?"))]
 295                         super().__init__(sm, nervlist)
 296                         self.last_buzzed = None
 297                         self.api().set_state(True)
 298                 def handle_pins_event(self):
 299                         pins = self.pins()
 300                         if pins.bell_ringing and not self.old_pins().bell_ringing: # first thing to check: edge detection
 301                                 # someone just pressed the bell
 302                                 logger.info("StateMachine: buzzing because of bell ringing in StateAuf")
 303                                 self.actor().act(Actor.CMD_BUZZ)
 304                         if not pins.space_active:
 305                                 logger.info("StateMachine: space switch turned off - starting leaving procedure")
 306                                 return StateMachine.StateAboutToLeave(self.state_machine)
 307                         if not pins.door_closed and self.old_pins().door_closed and random.random() <= HELLO_PROBABILITY:
 308                                 play_sound("hello")
 309                         return super().handle_pins_event()
 310                 def on_leave(self):
 311                         self.api().set_state(False)
 312
 313         class StateLocking(AbstractUnlockedState):
 314                 def __init__(self,sm):
 315                         # construct a nervlist
 316                         nervlist = [(CLOSE_REPEAT_TIMEOUT, lambda: self.actor().act(Actor.CMD_LOCK)) for t in range(CLOSE_REPEAT_NUMBER)]
 317                         nervlist += [(CLOSE_REPEAT_TIMEOUT, self.could_not_close)]
 318                         super().__init__(sm, nervlist)
 319                         if self.pins().door_closed: # this should always be true, but just to be sure...
 320                                 self.actor().act(Actor.CMD_LOCK)
 321                 def handle_pins_event(self):
 322                         pins = self.pins()
 323                         if not pins.door_closed:
 324                                 # TODO play a sound? This shouldn't happen, door was opened while we are locking
 325                                 logger.warning("StateMachine: door manually opened during locking")
 326                                 return StateMachine.StateAboutToOpen(self.state_machine)
 327                         # TODO do anything here if the switch is activated now?
 328                         return super().handle_pins_event()
 329                 def handle_cmd_unlock_event(self,callback):
 330                         callback("409 conflict: The sphinx is currently trying to lock the door. Try again later.")
 331                 def could_not_close(self):
 332                         logger.critical("StateMachine: Couldn't close door after %d tries. Going back to StateAboutToOpen." % CLOSE_REPEAT_NUMBER)
 333                         return StateMachine.StateAboutToOpen(self.state_machine)
 334
 335         class StateAboutToLeave(AbstractUnlockedState):
 336                 def __init__(self, sm):
 337                         nervlist = [(LEAVE_TIMEOUT, lambda: StateMachine.StateLocking(self.state_machine))]
 338                         super().__init__(sm, nervlist)
 339                 def handle_pins_event(self):
 340                         if not self.pins().door_closed:
 341                                 return StateMachine.StateLeaving(self.state_machine)
 342                         if self.pins().space_active:
 343                                 logger.info("Space re-activated, cancelling leaving procedure")
 344                                 return StateMachine.StateAuf(self.state_machine)
 345                         return super().handle_pins_event()
 346
 347         class StateLeaving(AbstractUnlockedState):
 348                 def __init__(self, sm):
 349                         nervlist = [(LEAVE_TIMEOUT, lambda: StateMachine.StateAboutToOpen(self.state_machine))]
 350                         super().__init__(sm, nervlist)
 351                 def handle_pins_event(self):
 352                         if self.pins().door_closed:
 353                                 logger.info("The space was left, locking the door")
 354                                 return StateMachine.StateLocking(self.state_machine)
 355                         if self.pins().space_active:
 356                                 logger.info("Space re-activated, cancelling leaving procedure")
 357                                 return StateMachine.StateAuf(self.state_machine)
 358                         return super().handle_pins_event()
 359
 360         def __init__(self, actor, waker, api, fallback = False):
 361                 self.actor = actor
 362                 self.api = api
 363                 self.callback = ThreadFunction(self._callback, name="StateMachine")
 364                 self.current_state = StateMachine.StateStart(self, fallback=fallback)
 365                 self.pins = None
 366                 self.old_pins = None
 367                 waker.register(lambda: self.callback(StateMachine.CMD_WAKEUP), 1.0) # wake up every second
 368                 # initially, the space is closed
 369                 api.set_state(False)
 370
 371         def stop (self):
 372                 self.callback.stop()
 373
 374         # actually call this.callback (is set in the constructor to make this thread safe)
 375         def _callback(self, cmd, arg=None):
 376                 # update pins
 377                 if cmd == StateMachine.CMD_PINS:
 378                         self.pins = arg
 379                 # handle stuff
 380                 newstate = self.current_state.handle_event(cmd,arg) # returns None or an instance of the new state
 381                 self.old_pins = self.pins
 382                 while newstate is not None:
 383                         assert isinstance(newstate, StateMachine.State), "I should get a state"
 384                         self.current_state.on_leave()
 385                         logger.info("StateMachine: Doing state transition %s -> %s" % (self.current_state.__class__.__name__, newstate.__class__.__name__))
 386                         self.current_state = newstate
 387                         newstate = self.current_state.handle_event(StateMachine.CMD_PINS, self.pins)