Edouard@2771: #!/usr/bin/env python
Edouard@2771: # -*- coding: utf-8 -*-
Edouard@2771: 
Edouard@2771: # This file is part of Beremiz
Edouard@2771: # Copyright (C) 2019: Edouard TISSERANT
Edouard@2771: # See COPYING file for copyrights details.
Edouard@2771: 
Edouard@2771: from __future__ import absolute_import
Edouard@2799: import errno
Edouard@2822: from threading import RLock, Timer
Edouard@2771: 
Edouard@2823: try:
Edouard@2823:     from runtime.spawn_subprocess import Popen
Edouard@2823: except ImportError:
Edouard@2823:     from subprocess import Popen
Edouard@2823: 
Edouard@2771: from twisted.web.server import Site
Edouard@2771: from twisted.web.resource import Resource
Edouard@2771: from twisted.internet import reactor
Edouard@2771: from twisted.web.static import File
Edouard@2771: 
Edouard@2771: from autobahn.twisted.websocket import WebSocketServerFactory, WebSocketServerProtocol
Edouard@2799: from autobahn.websocket.protocol import WebSocketProtocol
Edouard@2771: from autobahn.twisted.resource import  WebSocketResource
Edouard@2771: 
Edouard@3270: max_svghmi_sessions = None
Edouard@2822: svghmi_watchdog = None
Edouard@2771: 
Edouard@3271: 
Edouard@3271: svghmi_wait = PLCBinary.svghmi_wait
Edouard@3271: svghmi_wait.restype = ctypes.c_int # error or 0
Edouard@3271: svghmi_wait.argtypes = []
Edouard@3271: 
Edouard@3281: svghmi_continue_collect = ctypes.c_int.in_dll(PLCBinary, "svghmi_continue_collect")
Edouard@3281: 
Edouard@2774: svghmi_send_collect = PLCBinary.svghmi_send_collect
Edouard@2774: svghmi_send_collect.restype = ctypes.c_int # error or 0
Edouard@2774: svghmi_send_collect.argtypes = [
Edouard@3270:     ctypes.c_uint32,  # index
Edouard@2774:     ctypes.POINTER(ctypes.c_uint32),  # size
Edouard@2799:     ctypes.POINTER(ctypes.c_void_p)]  # data ptr
Edouard@2774: 
Edouard@3271: svghmi_reset = PLCBinary.svghmi_reset
Edouard@3271: svghmi_reset.restype = ctypes.c_int # error or 0
Edouard@3271: svghmi_reset.argtypes = [
Edouard@3271:     ctypes.c_uint32]  # index
Edouard@3271: 
Edouard@2774: svghmi_recv_dispatch = PLCBinary.svghmi_recv_dispatch
Edouard@2774: svghmi_recv_dispatch.restype = ctypes.c_int # error or 0
Edouard@2774: svghmi_recv_dispatch.argtypes = [
Edouard@3270:     ctypes.c_uint32,  # index
Edouard@2788:     ctypes.c_uint32,  # size
Edouard@2779:     ctypes.c_char_p]  # data ptr
Edouard@3270: 
Edouard@3270: class HMISessionMgr(object):
Edouard@3270:     def __init__(self):
Edouard@3270:         self.multiclient_sessions = set()
Edouard@3270:         self.watchdog_session = None
Edouard@3270:         self.session_count = 0
Edouard@3270:         self.lock = RLock()
Edouard@3270:         self.indexes = set()
Edouard@3270: 
Edouard@3270:     def next_index(self):
Edouard@3270:         if self.indexes:
Edouard@3270:             greatest = max(self.indexes)
Edouard@3270:             holes = set(range(greatest)) - self.indexes
Edouard@3270:             index = min(holes) if holes else greatest+1
Edouard@3270:         else:
Edouard@3270:             index = 0
Edouard@3270:         self.indexes.add(index)
Edouard@3270:         return index
Edouard@3270: 
Edouard@3270:     def free_index(self, index):
Edouard@3270:         self.indexes.remove(index)
Edouard@3270: 
Edouard@3270:     def register(self, session):
Edouard@3270:         global max_svghmi_sessions
Edouard@3270:         with self.lock:
Edouard@3270:             if session.is_watchdog_session:
Edouard@3270:                 # Creating a new watchdog session closes pre-existing one
Edouard@3270:                 if self.watchdog_session is not None:
Edouard@3270:                     self.unregister(self.watchdog_session)
Edouard@3270:                 else:
Edouard@3270:                     assert(self.session_count < max_svghmi_sessions)
Edouard@3270:                     self.session_count += 1
Edouard@3270: 
Edouard@3270:                 self.watchdog_session = session
Edouard@3270:             else:
Edouard@3270:                 assert(self.session_count < max_svghmi_sessions)
Edouard@3270:                 self.multiclient_sessions.add(session)
Edouard@3270:                 self.session_count += 1
Edouard@3270:             session.session_index = self.next_index()
Edouard@3270: 
Edouard@3270:     def unregister(self, session):
Edouard@3270:         with self.lock:
Edouard@3271:             if session.is_watchdog_session :
Edouard@3271:                 if self.watchdog_session != session:
Edouard@3271:                     return
Edouard@3270:                 self.watchdog_session = None
Edouard@3270:             else:
Edouard@3271:                 try:
Edouard@3278:                     self.multiclient_sessions.remove(session)
Edouard@3271:                 except KeyError:
Edouard@3271:                     return
Edouard@3271:             self.free_index(session.session_index)
Edouard@3270:             self.session_count -= 1
Edouard@3271:         session.kill()
Edouard@3273: 
Edouard@3270:     def close_all(self):
edouard@3272:         for session in self.iter_sessions():
edouard@3272:             self.unregister(session)
Edouard@3273: 
Edouard@3270:     def iter_sessions(self):
Edouard@3270:         with self.lock:
edouard@3272:             lst = list(self.multiclient_sessions)
edouard@3272:             if self.watchdog_session is not None:
edouard@3272:                 lst = [self.watchdog_session]+lst
edouard@3272:             for nxt_session in lst:
edouard@3272:                 yield nxt_session
Edouard@3270: 
Edouard@3270: 
Edouard@3270: svghmi_session_manager = HMISessionMgr()
Edouard@3270: 
Edouard@2774: 
Edouard@2771: class HMISession(object):
Edouard@2771:     def __init__(self, protocol_instance):
Edouard@2773:         self.protocol_instance = protocol_instance
Edouard@3270:         self._session_index = None
Edouard@3271:         self.closed = False
Edouard@3270: 
Edouard@3270:     @property
Edouard@3270:     def is_watchdog_session(self):
Edouard@3270:         return self.protocol_instance.has_watchdog
Edouard@3270: 
Edouard@3270:     @property
Edouard@3270:     def session_index(self):
Edouard@3270:         return self._session_index
Edouard@3270: 
Edouard@3270:     @session_index.setter
Edouard@3270:     def session_index(self, value):
Edouard@3270:         self._session_index = value
Edouard@2775: 
Edouard@3271:     def reset(self):
Edouard@3271:         return svghmi_reset(self.session_index)
Edouard@3271: 
Edouard@2799:     def close(self):
Edouard@3271:         if self.closed: return
Edouard@2799:         self.protocol_instance.sendClose(WebSocketProtocol.CLOSE_STATUS_CODE_NORMAL)
Edouard@2771: 
Edouard@3271:     def notify_closed(self):
Edouard@3271:         self.closed = True
Edouard@3271: 
Edouard@3271:     def kill(self):
Edouard@3271:         self.close()
Edouard@3271:         self.reset()
Edouard@3271: 
Edouard@2772:     def onMessage(self, msg):
Edouard@2779:         # pass message to the C side recieve_message()
Edouard@3271:         if self.closed: return
Edouard@3270:         return svghmi_recv_dispatch(self.session_index, len(msg), msg)
Edouard@2777: 
Edouard@2774:     def sendMessage(self, msg):
Edouard@3271:         if self.closed: return
Edouard@2799:         self.protocol_instance.sendMessage(msg, True)
Edouard@2799:         return 0
Edouard@2771: 
Edouard@2822: class Watchdog(object):
Edouard@2831:     def __init__(self, initial_timeout, interval, callback):
Edouard@2822:         self._callback = callback
Edouard@2822:         self.lock = RLock()
Edouard@2822:         self.initial_timeout = initial_timeout
Edouard@2831:         self.interval = interval
Edouard@2822:         self.callback = callback
Edouard@2822:         with self.lock:
Edouard@2822:             self._start()
Edouard@2822: 
Edouard@2831:     def _start(self, rearm=False):
Edouard@2831:         duration = self.interval if rearm else self.initial_timeout
Edouard@2831:         if duration:
Edouard@2831:             self.timer = Timer(duration, self.trigger)
Edouard@2831:             self.timer.start()
Edouard@2835:         else:
Edouard@2835:             self.timer = None
Edouard@2822: 
Edouard@2822:     def _stop(self):
Edouard@2822:         if self.timer is not None:
Edouard@2822:             self.timer.cancel()
Edouard@2822:             self.timer = None
Edouard@2822: 
Edouard@2822:     def cancel(self):
Edouard@2822:         with self.lock:
Edouard@2822:             self._stop()
Edouard@2822: 
Edouard@2832:     def feed(self, rearm=True):
Edouard@2822:         with self.lock:
Edouard@2822:             self._stop()
Edouard@2832:             self._start(rearm)
Edouard@2822: 
Edouard@2822:     def trigger(self):
Edouard@2822:         self._callback()
Edouard@3270:         # Don't repeat trigger periodically
Edouard@3270:         # # wait for initial timeout on re-start
Edouard@3270:         # self.feed(rearm=False)
Edouard@2822: 
Edouard@2771: class HMIProtocol(WebSocketServerProtocol):
Edouard@2771: 
Edouard@2771:     def __init__(self, *args, **kwargs):
Edouard@2771:         self._hmi_session = None
Edouard@3270:         self.has_watchdog = False
Edouard@2771:         WebSocketServerProtocol.__init__(self, *args, **kwargs)
Edouard@2771: 
edouard@3268:     def onConnect(self, request):
edouard@3268:         self.has_watchdog = request.params.get("mode", [None])[0] == "watchdog"
edouard@3268:         return WebSocketServerProtocol.onConnect(self, request)
edouard@3268: 
Edouard@2771:     def onOpen(self):
Edouard@3270:         global svghmi_session_manager
Edouard@2799:         assert(self._hmi_session is None)
Edouard@3278:         _hmi_session = HMISession(self)
Edouard@3278:         registered = svghmi_session_manager.register(_hmi_session)
Edouard@3278:         self._hmi_session = _hmi_session
Edouard@2771: 
Edouard@2771:     def onClose(self, wasClean, code, reason):
Edouard@3270:         global svghmi_session_manager
Edouard@3278:         if self._hmi_session is None : return
Edouard@3271:         self._hmi_session.notify_closed()
Edouard@3270:         svghmi_session_manager.unregister(self._hmi_session)
Edouard@2771:         self._hmi_session = None
Edouard@2771: 
Edouard@2771:     def onMessage(self, msg, isBinary):
Edouard@3270:         global svghmi_watchdog
Edouard@3278:         if self._hmi_session is None : return
Edouard@2822:         result = self._hmi_session.onMessage(msg)
Edouard@3270:         if result == 1 and self.has_watchdog:  # was heartbeat
Edouard@2822:             if svghmi_watchdog is not None:
Edouard@2822:                 svghmi_watchdog.feed()
Edouard@2775: 
Edouard@2779: class HMIWebSocketServerFactory(WebSocketServerFactory):
Edouard@2779:     protocol = HMIProtocol
Edouard@2779: 
edouard@3269: svghmi_servers = {}
Edouard@2775: svghmi_send_thread = None
Edouard@2775: 
edouard@3310: # python's errno on windows seems to have no ENODATA
edouard@3310: ENODATA = errno.ENODATA if hasattr(errno,"ENODATA") else None
edouard@3310: 
Edouard@2776: def SendThreadProc():
Edouard@3270:     global svghmi_session_manager
Edouard@2819:     size = ctypes.c_uint32()
Edouard@2819:     ptr = ctypes.c_void_p()
Edouard@2819:     res = 0
Edouard@3281:     while svghmi_continue_collect:
Edouard@3271:         svghmi_wait()
Edouard@3270:         for svghmi_session in svghmi_session_manager.iter_sessions():
Edouard@3270:             res = svghmi_send_collect(
Edouard@3270:                 svghmi_session.session_index,
Edouard@3270:                 ctypes.byref(size), ctypes.byref(ptr))
Edouard@3270:             if res == 0:
Edouard@3270:                 svghmi_session.sendMessage(
Edouard@3270:                     ctypes.string_at(ptr.value,size.value))
edouard@3310:             elif res == ENODATA:
Edouard@3270:                 # this happens when there is no data after wakeup
Edouard@3271:                 # because of hmi data refresh period longer than
Edouard@3270:                 # PLC common ticktime
Edouard@3271:                 pass
Edouard@3270:             else:
Edouard@3270:                 # this happens when finishing
Edouard@3270:                 break
Edouard@2776: 
Edouard@3284: def AddPathToSVGHMIServers(path, factory, *args, **kwargs):
edouard@3269:     for k,v in svghmi_servers.iteritems():
edouard@3269:         svghmi_root, svghmi_listener, path_list = v
Edouard@3284:         svghmi_root.putChild(path, factory(*args, **kwargs))
Edouard@2779: 
Edouard@2771: # Called by PLCObject at start
Edouard@2993: def _runtime_00_svghmi_start():
edouard@3269:     global svghmi_send_thread
Edouard@2771: 
Edouard@2771:     # start a thread that call the C part of SVGHMI
Edouard@2775:     svghmi_send_thread = Thread(target=SendThreadProc, name="SVGHMI Send")
Edouard@2775:     svghmi_send_thread.start()
Edouard@2771: 
Edouard@2771: 
Edouard@2771: # Called by PLCObject at stop
Edouard@2993: def _runtime_00_svghmi_stop():
edouard@3269:     global svghmi_send_thread, svghmi_session
Edouard@2822: 
Edouard@3270:     svghmi_session_manager.close_all()
Edouard@3270: 
Edouard@2775:     # plc cleanup calls svghmi_(locstring)_cleanup and unlocks send thread
Edouard@2775:     svghmi_send_thread.join()
Edouard@2775:     svghmi_send_thread = None
Edouard@2775: 
Edouard@2830: 
Edouard@2830: class NoCacheFile(File):
Edouard@2830:     def render_GET(self, request):
Edouard@2830:         request.setHeader(b"Cache-Control", b"no-cache, no-store")
Edouard@2830:         return File.render_GET(self, request)
Edouard@2830:     render_HEAD = render_GET
Edouard@2830: 
Edouard@2830: