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Class definition

Connection

class representing a connection to PVI manager

Typical usage example:

    pviConnection = Connection() # start a Pvi connection (to local PVI manager)

    # in case of a PVI remote connection:
    # pviConnection = Connection( timeout=15, IP='172.20.43.59', PN=20000 ) # start a remote Pvi connection

    line = Line( pviConnection.root, 'LNANSL', CD='LNANSL')
Source code in pvi\Connection.py 
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class Connection():
    '''
    class representing a connection to PVI manager

    Typical usage example:

    ```
        pviConnection = Connection() # start a Pvi connection (to local PVI manager)

        # in case of a PVI remote connection:
        # pviConnection = Connection( timeout=15, IP='172.20.43.59', PN=20000 ) # start a remote Pvi connection

        line = Line( pviConnection.root, 'LNANSL', CD='LNANSL')  


    ```
    '''
    # ----------------------------------------------------------------------------------
    def __init__(self, **kwargs : Union[str,int, float] ):
        """Initializes the connection to PVI manager

        Args:
            kwargs:
                timeout : timeout in [s] to PVI manager instance

                IP : ip address or host name for remote connection

                PN : port number for remote connection

                COMT : communication timeout
        """
        timeout = int(kwargs.get('timeout', 5 ))
        self._eventLoopIsRunning = False
        self._startTime = datetime.datetime.now()
        self._objectsArranged = False
        self._pviObjects = []
        self._rootObject = PviObject(None, T_POBJ_TYPE.POBJ_PVI, '@Pvi')

        self._linkIDs = {}
        self._hPvi = wintypes.DWORD(0)
        self._connected = None

        initParameter = ""
        if 'IP' in kwargs:
            initParameter = initParameter + 'IP=' + str(kwargs['IP']) + ' '
        if 'PN' in kwargs:
            initParameter = initParameter + 'PN=' + str(kwargs['PN']) + ' '
        if 'COMT' in kwargs:
            initParameter = initParameter + 'COMT=' + str(kwargs['COMT']) + ' '

        self._result = PviXInitialize( byref(self._hPvi), timeout, 0, initParameter, None )
        debuglog(f'PviXInitialize( {timeout}, 0, "{initParameter}", NULL)')

        if self._result == 0:
            self._rootObject._connection = self
            self._rootObject._hPvi = self._hPvi
            self.link(self._rootObject)
            # set global events
            for m in (POBJ_EVENT_PVI_CONNECT, POBJ_EVENT_PVI_DISCONN, POBJ_EVENT_PVI_ARRANGE):
                self._result = PviXSetGlobEventMsg( self._hPvi, m, PVI_HMSG_NIL, SET_PVIFUNCTION, 0 )
                if self._result != 0:
                    raise PviError(self._result)
        else:
            raise PviError(self._result)

    # ----------------------------------------------------------------------------------
    def __repr__(self):
        return f"Connection()"

    # ----------------------------------------------------------------------------------
    def __del__(self):
        PviXDeinitialize(self._hPvi)

    # ----------------------------------------------------------------------------------
    @property
    def hPvi(self) ->wintypes.DWORD:
        """
        Returns:
            wintypes.DWORD: handle for PviX.. functions
        """
        return self._hPvi

    # ----------------------------------------------------------------------------------
    @property
    def root(self) ->PviObject:
        """
        Returns:
           PviObject: the base object 'Pvi'
        """
        return self._rootObject

    @property
    def license(self) -> tuple:
        """read PVI license information

        Returns:
            A tuple( state, hardware, license, dongle, license-name )

        where    
        state is 'undefined' or 'trial' or 'runtime' or 'developer' or 'locked',  
        hardware is = 'B&R IPC' or 'PC',  
        license is 'B&R License' or '',  
        dongle is 'Pvi Dongle' or '',  
        license-name is a string  

        result may be ```('undefined', '', '', '', '', '')``` if PVI root object is not yet linked.

        """
        li = T_PVI_INFO_LICENCE()
        if self.root._linkID == 0: # root object not yet valid
            return ('undefined', '', '', '', '', '' )

        self._result = PviXRead( self._hPvi, self.root._linkID, POBJ_ACC_INFO_LICENCE  , None, 0, byref(li), sizeof(li) )
        if self._result == 0:
            try: 
                state = ('undefined', 'trial', 'runtime', 'developer', 'locked')[li.PviWorkState0]
                hardware = 'B&R IPC' if li.PviWorkState1 and 0x01 else 'PC'
                burlicence = 'B&R License' if li.PviWorkState1 and 0x02 else ''
                dongle = 'Pvi Dongle' if li.PviWorkState1 and 0x04 else ''
                return state, hardware, burlicence, dongle, str(li.LcName)
            except IndexError:
                pass
        else:
            raise PviError(self._result, self )
        return ('undefined', '', '', '', '', '' )

    # ----------------------------------------------------------------------------------
    def link(self, *args ):
        """
        registers new PviObject(s)

        *args : PviObject of list of PviObjects
        """
        for o in args:
            if isinstance(o, PviObject):
                self._pviObjects.append(o)
                if self._objectsArranged:
                    o._createAndLink(self)
            elif isinstance(o, list ):
                for oo in o:
                    self.link(oo)
            else:
                raise ValueError("only PviObject or list of PviObjects allowed !")
    # ----------------------------------------------------------------------------------

    def findObjectByName(self, name : str) ->PviObject :
        for o in self._pviObjects:
            if o.name == name:
                return o
        raise KeyError('PviObject not found by name')

    # ----------------------------------------------------------------------------------

    def findObjectByLinkID(self, linkID : wintypes.DWORD) ->PviObject :
        for o in self._pviObjects:
            if o._linkID == linkID:
                return o
        raise KeyError('PviObject not found by LinkID')      

    @property
    def connectionChanged(self) -> Optional[Callable]:
        """
        callback for 'connected to PVI-Manger'

            Args:
                cb: callback(status : bool) 

                where status is 'True' if connected, 'False' if disconnected

        typical example:

        ```
        pviConnection = Connection(IP="192.168.182.128") # start a remote Pvi connection

        pviConnection.connectionChanged = lambda s : print("connected" if s else "disconnected")
        ```
        """
        return self._connected


    @connectionChanged.setter
    def connectionChanged(self, cb : Callable):
        """
        set callback for 'connected to PVI-Manger'
        """
        if callable(cb):
            self._connected = cb
        else:
            raise TypeError("only callable allowed for Connection.connected")


    # ----------------------------------------------------------------------------------

    def _eventPviConnect( self, wParam, responseInfo ):
        """
        handle PVI connect event
        """
        debuglog("POBJ_EVENT_PVI_CONNECT")
        self._result = PviXReadResponse( self._hPvi, wParam, None, 0 )
        if self._connected:
            self._connected(True)

    # ----------------------------------------------------------------------------------
    def _eventPviDisconnect( self, wParam, responseInfo ):
        """
        handle PVI disconnect event
        """      
        self._result = PviXReadResponse( self._hPvi, wParam, None, 0 )
        self._pviObjects.clear()
        self._linkIDs.clear()
        self._objectsArranged = False
        if self._connected:
            self._connected(False)

    # ----------------------------------------------------------------------------------
    def _eventPviArrange( self, wParam, responseInfo ): 
        """
        handle pvi arrange event
        """
        self._pviTrialTimeCheck = None

        self._result = PviXReadResponse( self._hPvi, wParam, None, 0 )                
        debuglog("POBJ_EVENT_PVI_ARRANGE")

        # create and link objects
        for po in self._pviObjects:
            po._createAndLink(self)
        self._objectsArranged = True

    # ----------------------------------------------------------------------------------
    def _eventOther( self, wParam, responseInfo ):
        """
        handle other events
        """
        self._result = PviXReadResponse( self._hPvi, wParam, None, 0 )

    # ----------------------------------------------------------------------------------
    def doEvents(self):
        """         
        event loop - must be cyclically called

        typical usage example:

        ```
        pviConnection = Connection()
            ....
        while run:  
            pviConnection.doEvents()  
        ```
        """     
        wParam = WPARAM()
        lParam = LPARAM()
        hMsg = HANDLE()
        dataLen = wintypes.DWORD()      
        self._result = PviXGetNextResponse( self._hPvi, byref(wParam), byref(lParam), byref(hMsg), None )

        if wParam.value != 0:
            responseInfo = T_RESPONSE_INFO()
            self._result = PviXGetResponseInfo( self._hPvi, wParam, None, byref(dataLen), byref(responseInfo), sizeof(responseInfo) )

            # if responseInfo.ErrCode != 0:
            #     po = self.findObjectByLinkID(responseInfo.LinkID)
            #     print(f'{po.name} : nMode = {responseInfo.nMode}, nType = {responseInfo.nType}, ErrCode = {responseInfo.ErrCode}')

            if responseInfo.nType == POBJ_EVENT_PVI_CONNECT:
                self._eventPviConnect( wParam, responseInfo )
            elif responseInfo.nType == POBJ_EVENT_PVI_DISCONN:
                self._eventPviDisconnect( wParam, responseInfo )
            elif responseInfo.nType == POBJ_EVENT_PVI_ARRANGE:
                self._eventPviArrange( wParam, responseInfo )
            elif responseInfo.nType == POBJ_ACC_TYPE:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventDataType( wParam, responseInfo )
                else:
                    raise ValueError("linkID not found !")
            elif responseInfo.nType == POBJ_EVENT_DATA:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventData( wParam, responseInfo )
                else:
                    raise ValueError("linkID not found !")                    
            elif responseInfo.nType == POBJ_ACC_UPLOAD_STM:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventUploadStream( wParam, responseInfo, dataLen.value ) 
                else:
                    raise ValueError("linkID not found !")
            elif responseInfo.nType == POBJ_ACC_DOWNLOAD_STM:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventDownloadStream( wParam, responseInfo ) 
                else:
                    raise ValueError("linkID not found !") 
            elif responseInfo.nType == POBJ_EVENT_STATUS or responseInfo.nType == POBJ_ACC_STATUS:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventStatus( wParam, responseInfo )
                else:
                    raise ValueError("linkID not found !")                   
            elif responseInfo.nType == POBJ_EVENT_PROCEEDING:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventProceeding( wParam, responseInfo ) 
                else:
                    raise ValueError("linkID not found !")   
            elif responseInfo.nType == POBJ_ACC_LN_XML_LOGM_DATA:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventUploadLogData( wParam, responseInfo, dataLen.value ) 
                else:
                    raise ValueError("linkID not found !") 
            elif responseInfo.nType == POBJ_ACC_MOD_DATA:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    po._eventUploadModData( wParam, responseInfo, dataLen.value ) 
                else:
                    raise ValueError("linkID not found !")                                                                    
            elif responseInfo.nType == POBJ_EVENT_ERROR:
                po = self._linkIDs.get(responseInfo.LinkID, None )
                if po:
                    debuglog( f'{repr(po)}: error {responseInfo.ErrCode}')
                    po._eventError( wParam, responseInfo )
                else:
                    raise ValueError("linkID not found !")
            else:
                self._eventOther( wParam, responseInfo )
                # po = self.findObjectByLinkID(responseInfo.LinkID)
                # print(f'{po.name} : nMode = {responseInfo.nMode}, nType = {responseInfo.nType}, ErrCode = {responseInfo.ErrCode}')                


   # ----------------------------------------------------------------------------------
    def start(self, callback : Union[Callable,None] = None ):
        """         
        start event loop

        Args:
            callback :  function that will be cyclically called in event loop or 'None'.
                        callback is called with one boolean argument which signals the
                        first call with 'True' all subsequent calls will be done with
                        argument 'False'

        typical usage example:

        ```
        pviConnection = Connection()

        def runtimeMonitor( init : bool ):
            if datetime.datetime.now() - startTime > datetime.timedelta(seconds = 10):
                print("done !")
                pviConnection.stop() # exit

        pviConnection.start( runtimeMonitor )
        ```
        """
        self._eventLoopIsRunning = True
        if( callback ) : callback(True)
        while( self._eventLoopIsRunning ):
            sleep(0.05)
            if( callback ) : callback(False)
            self.doEvents()

    # ----------------------------------------------------------------------------------
    def stop(self):
        """
        stop event loop
        typical usage example:

        ```
        pviConnection = Connection()
          ....
        pviConnection.stop()  
        ```
        """
        self._eventLoopIsRunning = False
   # ----------------------------------------------------------------------------------
    def sleep( self, millis : int ):
        """
        helper function for waiting actions
        typical usage example:

        Args:
            millis: sleep time in milliseconds
        ```
        pviConnection = Connection()
            ....
        pviConnection.sleep(2000) # pause code for 2 seconds  
        ```   
        """
        t1 = datetime.datetime.now()
        while True:
            self.doEvents()
            if (datetime.datetime.now() - t1) >= datetime.timedelta( microseconds= millis*1000):
                break

connectionChanged: Optional[Callable] property writable

callback for 'connected to PVI-Manger'

Args:
    cb: callback(status : bool)

    where status is 'True' if connected, 'False' if disconnected

typical example:

pviConnection = Connection(IP="192.168.182.128") # start a remote Pvi connection

pviConnection.connectionChanged = lambda s : print("connected" if s else "disconnected")

hPvi: wintypes.DWORD property

Returns:

Type Description
DWORD

wintypes.DWORD: handle for PviX.. functions

license: tuple property

read PVI license information

Returns:

Type Description
tuple

A tuple( state, hardware, license, dongle, license-name )

where
state is 'undefined' or 'trial' or 'runtime' or 'developer' or 'locked',
hardware is = 'B&R IPC' or 'PC',
license is 'B&R License' or '',
dongle is 'Pvi Dongle' or '',
license-name is a string

result may be ('undefined', '', '', '', '', '') if PVI root object is not yet linked.

root: PviObject property

Returns:

Name Type Description
PviObject PviObject

the base object 'Pvi'

__init__(**kwargs)

Initializes the connection to PVI manager

Parameters:

Name Type Description Default
kwargs Union[str, int, float]

timeout : timeout in [s] to PVI manager instance

IP : ip address or host name for remote connection

PN : port number for remote connection

COMT : communication timeout

 {}
Source code in pvi\Connection.py 
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def __init__(self, **kwargs : Union[str,int, float] ):
    """Initializes the connection to PVI manager

    Args:
        kwargs:
            timeout : timeout in [s] to PVI manager instance

            IP : ip address or host name for remote connection

            PN : port number for remote connection

            COMT : communication timeout
    """
    timeout = int(kwargs.get('timeout', 5 ))
    self._eventLoopIsRunning = False
    self._startTime = datetime.datetime.now()
    self._objectsArranged = False
    self._pviObjects = []
    self._rootObject = PviObject(None, T_POBJ_TYPE.POBJ_PVI, '@Pvi')

    self._linkIDs = {}
    self._hPvi = wintypes.DWORD(0)
    self._connected = None

    initParameter = ""
    if 'IP' in kwargs:
        initParameter = initParameter + 'IP=' + str(kwargs['IP']) + ' '
    if 'PN' in kwargs:
        initParameter = initParameter + 'PN=' + str(kwargs['PN']) + ' '
    if 'COMT' in kwargs:
        initParameter = initParameter + 'COMT=' + str(kwargs['COMT']) + ' '

    self._result = PviXInitialize( byref(self._hPvi), timeout, 0, initParameter, None )
    debuglog(f'PviXInitialize( {timeout}, 0, "{initParameter}", NULL)')

    if self._result == 0:
        self._rootObject._connection = self
        self._rootObject._hPvi = self._hPvi
        self.link(self._rootObject)
        # set global events
        for m in (POBJ_EVENT_PVI_CONNECT, POBJ_EVENT_PVI_DISCONN, POBJ_EVENT_PVI_ARRANGE):
            self._result = PviXSetGlobEventMsg( self._hPvi, m, PVI_HMSG_NIL, SET_PVIFUNCTION, 0 )
            if self._result != 0:
                raise PviError(self._result)
    else:
        raise PviError(self._result)

doEvents()

event loop - must be cyclically called

typical usage example:

pviConnection = Connection()
    ....
while run:  
    pviConnection.doEvents()
Source code in pvi\Connection.py 
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def doEvents(self):
    """         
    event loop - must be cyclically called

    typical usage example:

    ```
    pviConnection = Connection()
        ....
    while run:  
        pviConnection.doEvents()  
    ```
    """     
    wParam = WPARAM()
    lParam = LPARAM()
    hMsg = HANDLE()
    dataLen = wintypes.DWORD()      
    self._result = PviXGetNextResponse( self._hPvi, byref(wParam), byref(lParam), byref(hMsg), None )

    if wParam.value != 0:
        responseInfo = T_RESPONSE_INFO()
        self._result = PviXGetResponseInfo( self._hPvi, wParam, None, byref(dataLen), byref(responseInfo), sizeof(responseInfo) )

        # if responseInfo.ErrCode != 0:
        #     po = self.findObjectByLinkID(responseInfo.LinkID)
        #     print(f'{po.name} : nMode = {responseInfo.nMode}, nType = {responseInfo.nType}, ErrCode = {responseInfo.ErrCode}')

        if responseInfo.nType == POBJ_EVENT_PVI_CONNECT:
            self._eventPviConnect( wParam, responseInfo )
        elif responseInfo.nType == POBJ_EVENT_PVI_DISCONN:
            self._eventPviDisconnect( wParam, responseInfo )
        elif responseInfo.nType == POBJ_EVENT_PVI_ARRANGE:
            self._eventPviArrange( wParam, responseInfo )
        elif responseInfo.nType == POBJ_ACC_TYPE:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventDataType( wParam, responseInfo )
            else:
                raise ValueError("linkID not found !")
        elif responseInfo.nType == POBJ_EVENT_DATA:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventData( wParam, responseInfo )
            else:
                raise ValueError("linkID not found !")                    
        elif responseInfo.nType == POBJ_ACC_UPLOAD_STM:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventUploadStream( wParam, responseInfo, dataLen.value ) 
            else:
                raise ValueError("linkID not found !")
        elif responseInfo.nType == POBJ_ACC_DOWNLOAD_STM:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventDownloadStream( wParam, responseInfo ) 
            else:
                raise ValueError("linkID not found !") 
        elif responseInfo.nType == POBJ_EVENT_STATUS or responseInfo.nType == POBJ_ACC_STATUS:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventStatus( wParam, responseInfo )
            else:
                raise ValueError("linkID not found !")                   
        elif responseInfo.nType == POBJ_EVENT_PROCEEDING:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventProceeding( wParam, responseInfo ) 
            else:
                raise ValueError("linkID not found !")   
        elif responseInfo.nType == POBJ_ACC_LN_XML_LOGM_DATA:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventUploadLogData( wParam, responseInfo, dataLen.value ) 
            else:
                raise ValueError("linkID not found !") 
        elif responseInfo.nType == POBJ_ACC_MOD_DATA:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                po._eventUploadModData( wParam, responseInfo, dataLen.value ) 
            else:
                raise ValueError("linkID not found !")                                                                    
        elif responseInfo.nType == POBJ_EVENT_ERROR:
            po = self._linkIDs.get(responseInfo.LinkID, None )
            if po:
                debuglog( f'{repr(po)}: error {responseInfo.ErrCode}')
                po._eventError( wParam, responseInfo )
            else:
                raise ValueError("linkID not found !")
        else:
            self._eventOther( wParam, responseInfo )

registers new PviObject(s)

*args : PviObject of list of PviObjects

Source code in pvi\Connection.py 
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def link(self, *args ):
    """
    registers new PviObject(s)

    *args : PviObject of list of PviObjects
    """
    for o in args:
        if isinstance(o, PviObject):
            self._pviObjects.append(o)
            if self._objectsArranged:
                o._createAndLink(self)
        elif isinstance(o, list ):
            for oo in o:
                self.link(oo)
        else:
            raise ValueError("only PviObject or list of PviObjects allowed !")

sleep(millis)

helper function for waiting actions typical usage example:

Parameters:

Name Type Description Default
millis int

sleep time in milliseconds

 required 
pviConnection = Connection()
    ....
pviConnection.sleep(2000) # pause code for 2 seconds
Source code in pvi\Connection.py 
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def sleep( self, millis : int ):
    """
    helper function for waiting actions
    typical usage example:

    Args:
        millis: sleep time in milliseconds
    ```
    pviConnection = Connection()
        ....
    pviConnection.sleep(2000) # pause code for 2 seconds  
    ```   
    """
    t1 = datetime.datetime.now()
    while True:
        self.doEvents()
        if (datetime.datetime.now() - t1) >= datetime.timedelta( microseconds= millis*1000):
            break

start(callback=None)

start event loop

Parameters:

Name Type Description Default
callback

function that will be cyclically called in event loop or 'None'. callback is called with one boolean argument which signals the first call with 'True' all subsequent calls will be done with argument 'False'

 None

typical usage example:

pviConnection = Connection()

def runtimeMonitor( init : bool ):
    if datetime.datetime.now() - startTime > datetime.timedelta(seconds = 10):
        print("done !")
        pviConnection.stop() # exit

pviConnection.start( runtimeMonitor )
Source code in pvi\Connection.py 
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def start(self, callback : Union[Callable,None] = None ):
    """         
    start event loop

    Args:
        callback :  function that will be cyclically called in event loop or 'None'.
                    callback is called with one boolean argument which signals the
                    first call with 'True' all subsequent calls will be done with
                    argument 'False'

    typical usage example:

    ```
    pviConnection = Connection()

    def runtimeMonitor( init : bool ):
        if datetime.datetime.now() - startTime > datetime.timedelta(seconds = 10):
            print("done !")
            pviConnection.stop() # exit

    pviConnection.start( runtimeMonitor )
    ```
    """
    self._eventLoopIsRunning = True
    if( callback ) : callback(True)
    while( self._eventLoopIsRunning ):
        sleep(0.05)
        if( callback ) : callback(False)
        self.doEvents()

stop()

stop event loop typical usage example:

pviConnection = Connection()
  ....
pviConnection.stop()
Source code in pvi\Connection.py 
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def stop(self):
    """
    stop event loop
    typical usage example:

    ```
    pviConnection = Connection()
      ....
    pviConnection.stop()  
    ```
    """
    self._eventLoopIsRunning = False