beremiz

SVGHMI: added a watchdog. To ensure that the whole chain is checked, watchdog use a periodic echo of a hearteat variable. JS client code systematically register /HEARTBEAT at 1s update freq, and reacts on updates of /HEARTBEAT by systematically incrementing it. C code catch /HEARTBEAT update and feeds python-implemented watchdog. For now, watchdog does nothing when tiggered
svghmi
2020-01-10, Edouard Tisserant
9101a72a1da0
Parents d92d201d22e1
Children d631f8671c75
SVGHMI: added a watchdog. To ensure that the whole chain is checked, watchdog use a periodic echo of a hearteat variable. JS client code systematically register /HEARTBEAT at 1s update freq, and reacts on updates of /HEARTBEAT by systematically incrementing it. C code catch /HEARTBEAT update and feeds python-implemented watchdog. For now, watchdog does nothing when tiggered
6 files changed, 148 insertions(+), 23 deletions(-)
  • +34 -0
    svghmi/gen_index_xhtml.xslt
  • +2 -0
    svghmi/gen_index_xhtml.ysl2
  • +8 -2
    svghmi/svghmi.c
  • +14 -0
    svghmi/svghmi.js
  • +39 -15
    svghmi/svghmi.py
  • +51 -6
    svghmi/svghmi_server.py
    • --- a/svghmi/gen_index_xhtml.xslt Wed Dec 18 13:31:22 2019 +0100
    +++ b/svghmi/gen_index_xhtml.xslt Fri Jan 10 13:15:07 2020 +0100
    @@ -264,6 +264,12 @@
    </xsl:text>
    <xsl:text>
    </xsl:text>
    + <xsl:text>var heartbeat_index = </xsl:text>
    + <xsl:value-of select="$indexed_hmitree/*[@hmipath = '/HEARTBEAT']/@index"/>
    + <xsl:text>;
    +</xsl:text>
    + <xsl:text>
    +</xsl:text>
    <xsl:text>var hmitree_types = [
    </xsl:text>
    <xsl:for-each select="$indexed_hmitree/*">
    @@ -576,6 +582,32 @@
    </xsl:text>
    <xsl:text>
    </xsl:text>
    + <xsl:text>// artificially subscribe the watchdog widget to "/heartbeat" hmi variable
    +</xsl:text>
    + <xsl:text>// Since dispatch directly calls change_hmi_value,
    +</xsl:text>
    + <xsl:text>// PLC will periodically send variable at given frequency
    +</xsl:text>
    + <xsl:text>subscribers[heartbeat_index].add({
    +</xsl:text>
    + <xsl:text> /* type: "Watchdog", */
    +</xsl:text>
    + <xsl:text> frequency: 1,
    +</xsl:text>
    + <xsl:text> indexes: [heartbeat_index],
    +</xsl:text>
    + <xsl:text> dispatch: function(value) {
    +</xsl:text>
    + <xsl:text> console.log("Heartbeat" + value);
    +</xsl:text>
    + <xsl:text> change_hmi_value(this.indexes[0], "+1");
    +</xsl:text>
    + <xsl:text> }
    +</xsl:text>
    + <xsl:text>});
    +</xsl:text>
    + <xsl:text>
    +</xsl:text>
    <xsl:text>function update_subscriptions() {
    </xsl:text>
    <xsl:text> let delta = [];
    @@ -592,6 +624,8 @@
    </xsl:text>
    <xsl:text>
    </xsl:text>
    + <xsl:text> // subscribing with a zero period is unsubscribing
    +</xsl:text>
    <xsl:text> let new_period = 0;
    </xsl:text>
    <xsl:text> if(widgets.size &gt; 0) {
    --- a/svghmi/gen_index_xhtml.ysl2 Wed Dec 18 13:31:22 2019 +0100
    +++ b/svghmi/gen_index_xhtml.ysl2 Fri Jan 10 13:15:07 2020 +0100
    @@ -238,6 +238,8 @@
    }
    | }
    |
    + | var heartbeat_index = «$indexed_hmitree/*[@hmipath = '/HEARTBEAT']/@index»;
    + |
    | var hmitree_types = [
    foreach "$indexed_hmitree/*" {
    --- a/svghmi/svghmi.c Wed Dec 18 13:31:22 2019 +0100
    +++ b/svghmi/svghmi.c Fri Jan 10 13:15:07 2020 +0100
    @@ -257,16 +257,19 @@
    subscribe = 2
    } cmd_from_JS;
    +// Returns :
    +// 0 is OK, <0 is error, 1 is heartbeat
    int svghmi_recv_dispatch(uint32_t size, const uint8_t *ptr){
    const uint8_t* cursor = ptr + HMI_HASH_SIZE;
    const uint8_t* end = ptr + size;
    + int was_hearbeat = 0;
    /* match hmitree fingerprint */
    if(size <= HMI_HASH_SIZE || memcmp(ptr, hmi_hash, HMI_HASH_SIZE) != 0)
    {
    printf("svghmi_recv_dispatch MISMATCH !!\n");
    - return EINVAL;
    + return -EINVAL;
    }
    while(cursor < end)
    @@ -279,6 +282,9 @@
    {
    uint32_t index = *(uint32_t*)(cursor);
    uint8_t const *valptr = cursor + sizeof(uint32_t);
    +
    + if(index == heartbeat_index)
    + was_hearbeat = 1;
    if(index < HMI_ITEM_COUNT)
    {
    @@ -344,6 +350,6 @@
    }
    cursor += progress;
    }
    - return 0;
    + return was_hearbeat;
    }
    --- a/svghmi/svghmi.js Wed Dec 18 13:31:22 2019 +0100
    +++ b/svghmi/svghmi.js Fri Jan 10 13:15:07 2020 +0100
    @@ -115,6 +115,19 @@
    // hmitree indexed array of Sets of widgets objects
    var subscribers = hmitree_types.map(_ignored => new Set());
    +// artificially subscribe the watchdog widget to "/heartbeat" hmi variable
    +// Since dispatch directly calls change_hmi_value,
    +// PLC will periodically send variable at given frequency
    +subscribers[heartbeat_index].add({
    + /* type: "Watchdog", */
    + frequency: 1,
    + indexes: [heartbeat_index],
    + dispatch: function(value) {
    + console.log("Heartbeat" + value);
    + change_hmi_value(this.indexes[0], "+1");
    + }
    +});
    +
    function update_subscriptions() {
    let delta = [];
    for(let index = 0; index < subscribers.length; index++){
    @@ -123,6 +136,7 @@
    // periods are in ms
    let previous_period = subscriptions[index];
    + // subscribing with a zero period is unsubscribing
    let new_period = 0;
    if(widgets.size > 0) {
    let maxfreq = 0;
    --- a/svghmi/svghmi.py Wed Dec 18 13:31:22 2019 +0100
    +++ b/svghmi/svghmi.py Fri Jan 10 13:15:07 2020 +0100
    @@ -10,7 +10,7 @@
    import os
    import shutil
    from itertools import izip, imap
    -from pprint import pprint, pformat
    +from pprint import pformat
    import hashlib
    import weakref
    @@ -43,7 +43,7 @@
    ScriptDirectory = paths.AbsDir(__file__)
    class HMITreeNode(object):
    - def __init__(self, path, name, nodetype, iectype = None, vartype = None, hmiclass = None):
    + def __init__(self, path, name, nodetype, iectype = None, vartype = None, cpath = None, hmiclass = None):
    self.path = path
    self.name = name
    self.nodetype = nodetype
    @@ -52,6 +52,8 @@
    if iectype is not None:
    self.iectype = iectype
    self.vartype = vartype
    + self.cpath = cpath
    +
    if nodetype in ["HMI_NODE", "HMI_ROOT"]:
    self.children = []
    @@ -133,12 +135,15 @@
    on_hmitree_update = None
    +SPECIAL_NODES = [("heartbeat", "HMI_INT")]
    + # ("current_page", "HMI_STRING")])
    +
    class SVGHMILibrary(POULibrary):
    def GetLibraryPath(self):
    return paths.AbsNeighbourFile(__file__, "pous.xml")
    def Generate_C(self, buildpath, varlist, IECCFLAGS):
    - global hmi_tree_root, on_hmitree_update, hmi_tree_unique_id
    + global hmi_tree_root, on_hmitree_update
    """
    PLC Instance Tree:
    @@ -179,25 +184,21 @@
    hmi_tree_root = HMITreeNode(None, "/", "HMI_ROOT")
    - # add special nodes
    - map(lambda (n,t): hmi_tree_root.children.append(HMITreeNode(None,n,t)), [
    - ("plc_status", "HMI_PLC_STATUS"),
    - ("current_page", "HMI_CURRENT_PAGE")])
    -
    # deduce HMI tree from PLC HMI_* instances
    for v in hmi_types_instances:
    - path = v["C_path"].split(".")
    + path = v["IEC_path"].split(".")
    # ignores variables starting with _TMP_
    if path[-1].startswith("_TMP_"):
    continue
    derived = v["derived"]
    kwargs={}
    if derived == "HMI_NODE":
    + # TODO : make problem if HMI_NODE used in CONFIG or RESOURCE
    name = path[-2]
    kwargs['hmiclass'] = path[-1]
    else:
    name = path[-1]
    - new_node = HMITreeNode(path, name, derived, v["type"], v["vartype"], **kwargs)
    + new_node = HMITreeNode(path, name, derived, v["type"], v["vartype"], v["C_path"], **kwargs)
    hmi_tree_root.place_node(new_node)
    if on_hmitree_update is not None:
    @@ -207,12 +208,26 @@
    extern_variables_declarations = []
    buf_index = 0
    item_count = 0
    + found_heartbeat = False
    +
    + # find heartbeat in hmi tree
    + # it is supposed to come first, but some HMI_* intances
    + # in config's globals might shift them
    + hearbeat_IEC_path = ['CONFIG', 'HEARTBEAT']
    for node in hmi_tree_root.traverse():
    - if hasattr(node, "iectype") and \
    - node.nodetype not in ["HMI_NODE"]:
    + if node.path == hearbeat_IEC_path:
    + hmi_tree_hearbeat_index = item_count
    + found_heartbeat = True
    + extern_variables_declarations += [
    + "#define heartbeat_index "+str(hmi_tree_hearbeat_index)
    + ]
    + break;
    +
    + for node in hmi_tree_root.traverse():
    + if hasattr(node, "iectype") and node.nodetype != "HMI_NODE":
    sz = DebugTypesSize.get(node.iectype, 0)
    variable_decl_array += [
    - "{&(" + ".".join(node.path) + "), " + node.iectype + {
    + "{&(" + node.cpath + "), " + node.iectype + {
    "EXT": "_P_ENUM",
    "IN": "_P_ENUM",
    "MEM": "_O_ENUM",
    @@ -226,11 +241,13 @@
    extern_variables_declarations += [
    "extern __IEC_" + node.iectype + "_" +
    "t" if node.vartype is "VAR" else "p"
    - + ".".join(node.path) + ";"]
    + + node.cpath + ";"]
    +
    + assert(found_heartbeat)
    # TODO : filter only requiered external declarations
    for v in varlist :
    - if v["C_path"].find('.') < 0 and v["vartype"] == "FB" :
    + if v["C_path"].find('.') < 0 : # and v["vartype"] == "FB" :
    extern_variables_declarations += [
    "extern %(type)s %(C_path)s;" % v]
    @@ -530,3 +547,10 @@
    if not os.path.isfile(svgfile):
    svgfile = None
    open_svg(svgfile)
    +
    + def CTNGlobalInstances(self):
    + # view_name = self.BaseParams.getName()
    + # return [ (view_name + "_" + name, iec_type, "") for name, iec_type in SPECIAL_NODES]
    + # TODO : move to library level for multiple hmi
    + return [(name, iec_type, "") for name, iec_type in SPECIAL_NODES]
    +
    --- a/svghmi/svghmi_server.py Wed Dec 18 13:31:22 2019 +0100
    +++ b/svghmi/svghmi_server.py Fri Jan 10 13:15:07 2020 +0100
    @@ -7,6 +7,7 @@
    from __future__ import absolute_import
    import errno
    +from threading import RLock, Timer
    from twisted.web.server import Site
    from twisted.web.resource import Resource
    @@ -20,8 +21,10 @@
    # TODO multiclient :
    # session list lock
    # svghmi_sessions = []
    +# svghmi_watchdogs = []
    svghmi_session = None
    +svghmi_watchdog = None
    svghmi_send_collect = PLCBinary.svghmi_send_collect
    svghmi_send_collect.restype = ctypes.c_int # error or 0
    @@ -61,15 +64,45 @@
    def onMessage(self, msg):
    # pass message to the C side recieve_message()
    - svghmi_recv_dispatch(len(msg), msg)
    + return svghmi_recv_dispatch(len(msg), msg)
    # TODO multiclient : pass client index as well
    -
    def sendMessage(self, msg):
    self.protocol_instance.sendMessage(msg, True)
    return 0
    +class Watchdog(object):
    + def __init__(self, initial_timeout, callback):
    + self._callback = callback
    + self.lock = RLock()
    + self.initial_timeout = initial_timeout
    + self.callback = callback
    + with self.lock:
    + self._start()
    +
    + def _start(self):
    + self.timer = Timer(self.initial_timeout, self.trigger)
    + self.timer.start()
    +
    + def _stop(self):
    + if self.timer is not None:
    + self.timer.cancel()
    + self.timer = None
    +
    + def cancel(self):
    + with self.lock:
    + self._stop()
    +
    + def feed(self):
    + with self.lock:
    + self._stop()
    + self._start()
    +
    + def trigger(self):
    + self._callback()
    + self.feed()
    +
    class HMIProtocol(WebSocketServerProtocol):
    def __init__(self, *args, **kwargs):
    @@ -85,7 +118,11 @@
    def onMessage(self, msg, isBinary):
    assert(self._hmi_session is not None)
    - self._hmi_session.onMessage(msg)
    +
    + result = self._hmi_session.onMessage(msg)
    + if result == 1 : # was heartbeat
    + if svghmi_watchdog is not None:
    + svghmi_watchdog.feed()
    class HMIWebSocketServerFactory(WebSocketServerFactory):
    protocol = HMIProtocol
    @@ -114,11 +151,13 @@
    break
    -
    +def watchdog_trigger():
    + print("SVGHMI watchdog trigger")
    +
    # Called by PLCObject at start
    def _runtime_svghmi0_start():
    - global svghmi_listener, svghmi_root, svghmi_send_thread
    + global svghmi_listener, svghmi_root, svghmi_send_thread, svghmi_watchdog
    svghmi_root = Resource()
    svghmi_root.putChild("ws", WebSocketResource(HMIWebSocketServerFactory()))
    @@ -129,10 +168,16 @@
    svghmi_send_thread = Thread(target=SendThreadProc, name="SVGHMI Send")
    svghmi_send_thread.start()
    + svghmi_watchdog = Watchdog(5, watchdog_trigger)
    # Called by PLCObject at stop
    def _runtime_svghmi0_stop():
    - global svghmi_listener, svghmi_root, svghmi_send_thread, svghmi_session
    + global svghmi_listener, svghmi_root, svghmi_send_thread, svghmi_session, svghmi_watchdog
    +
    + if svghmi_watchdog is not None:
    + svghmi_watchdog.cancel()
    + svghmi_watchdog = None
    +
    if svghmi_session is not None:
    svghmi_session.close()
    svghmi_root.delEntity("ws")