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@2773: # TODO multiclient :
Edouard@2773: # session list lock
Edouard@2773: # svghmi_sessions = []
Edouard@2822: # svghmi_watchdogs = []
Edouard@2773: 
Edouard@2773: svghmi_session = None
Edouard@2822: svghmi_watchdog = None
Edouard@2771: 
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@2774:     ctypes.POINTER(ctypes.c_uint32),  # size
Edouard@2799:     ctypes.POINTER(ctypes.c_void_p)]  # data ptr
Edouard@2774: # TODO multiclient : switch to arrays
Edouard@2774: 
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@2788:     ctypes.c_uint32,  # size
Edouard@2779:     ctypes.c_char_p]  # data ptr
Edouard@2774: # TODO multiclient : switch to arrays
Edouard@2774: 
Edouard@2771: class HMISession(object):
Edouard@2771:     def __init__(self, protocol_instance):
Edouard@2773:         global svghmi_session
Edouard@2799:         
Edouard@2799:         # Single client :
Edouard@2799:         # Creating a new HMISession closes pre-existing HMISession
Edouard@2799:         if svghmi_session is not None:
Edouard@2799:             svghmi_session.close()
Edouard@2773:         svghmi_session = self
Edouard@2773:         self.protocol_instance = protocol_instance
Edouard@2771: 
Edouard@2771:         # TODO multiclient :
Edouard@2773:         # svghmi_sessions.append(self)
Edouard@2771:         # get a unique bit index amont other svghmi_sessions,
Edouard@2771:         # so that we can match flags passed by C->python callback
Edouard@2775: 
Edouard@2799:     def close(self):
Edouard@2773:         global svghmi_session
Edouard@2799:         if svghmi_session == self:
Edouard@2799:             svghmi_session = None
Edouard@2799:         self.protocol_instance.sendClose(WebSocketProtocol.CLOSE_STATUS_CODE_NORMAL)
Edouard@2771: 
Edouard@2772:     def onMessage(self, msg):
Edouard@2779:         # pass message to the C side recieve_message()
Edouard@2822:         return svghmi_recv_dispatch(len(msg), msg)
Edouard@2771: 
Edouard@2771:         # TODO multiclient : pass client index as well
Edouard@2777: 
Edouard@2774:     def sendMessage(self, msg):
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@2832:         # wait for initial timeout on re-start
Edouard@2832:         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@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@2799:         assert(self._hmi_session is None)
Edouard@2771:         self._hmi_session = HMISession(self)
Edouard@2771: 
Edouard@2771:     def onClose(self, wasClean, code, reason):
Edouard@2771:         self._hmi_session = None
Edouard@2771: 
Edouard@2771:     def onMessage(self, msg, isBinary):
Edouard@2799:         assert(self._hmi_session is not None)
Edouard@2822: 
Edouard@2822:         result = self._hmi_session.onMessage(msg)
Edouard@2822:         if result == 1 :  # 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@2776: def SendThreadProc():
Edouard@2819:     global svghmi_session
Edouard@2819:     size = ctypes.c_uint32()
Edouard@2819:     ptr = ctypes.c_void_p()
Edouard@2819:     res = 0
Edouard@2819:     while True:
Edouard@2819:         res=svghmi_send_collect(ctypes.byref(size), ctypes.byref(ptr))
Edouard@2819:         if res == 0:
Edouard@2819:             # TODO multiclient : dispatch to sessions
Edouard@2819:             if svghmi_session is not None:
Edouard@2819:                 svghmi_session.sendMessage(ctypes.string_at(ptr.value,size.value))
Edouard@2819:         elif res == errno.ENODATA:
Edouard@2819:             # this happens when there is no data after wakeup
Edouard@2819:             # because of hmi data refresh period longer than PLC common ticktime
Edouard@2819:             pass 
Edouard@2819:         else:
Edouard@2819:             # this happens when finishing
Edouard@2819:             break
Edouard@2776: 
edouard@3269: def AddPathToSVGHMIServers(path, factory):
edouard@3269:     for k,v in svghmi_servers.iteritems():
edouard@3269:         svghmi_root, svghmi_listener, path_list = v
edouard@3269:         svghmi_root.putChild(path, factory())
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@2799:     if svghmi_session is not None:
Edouard@2799:         svghmi_session.close()
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: