Hey,

first of all, awesome work guys! I am really happy this project exists :+1:

In the last days I was using the opc ua server for some monitoring of energy usage. Now, I got to the point that I can not report any errors which occurred while reading the energy stats in the opc ua server. As I understand it, reporting events like errors right now in OPC UA only work using the subscription or history method.

As I do only want to connect once a day to the opc ua server, i discarded the subscription method. (band with / data usage reasons)

What do you think? Is there any plan or idea how to implement the history function for the opc ua server?

If I would get a better understanding and some help, maybe I could also start working on it.

changes:

    def save_event(self, event):
        with self._lock:
            _c_sub = self._conn.cursor()

            table = self._get_table_name(event.SourceNode) #Emitting node is not always the Source (event.SourceNode)
            columns, placeholders, evtup = self._format_event(event) #from event_prop_dict
            event_type = event.EventType  # useful for troubleshooting database

            # insert the event into the database
            try:
                _c_sub.execute(
                    'INSERT INTO "{tn}" ("_Id", "_Timestamp", "_EventTypeName", {co}) VALUES (NULL, "{ts}", "{et}", {pl})'
                    .format(tn=table, co=columns, ts=event.Time, et=event_type, pl=placeholders), evtup)

            except sqlite3.Error as e:
                self.logger.error('Historizing SQL Insert Error for events from %s: %s', event.SourceNode, e)

            self._conn.commit()

            # get this node's period from the period dict and calculate the limit
            period = self._datachanges_period[event.SourceNode]

            if period:
                # after the insert, if a period was specified delete all records older than period
                date_limit = datetime.utcnow() - period

                try:
                    _c_sub.execute('DELETE FROM "{tn}" WHERE Time < ?'.format(tn=table),
                                   (date_limit.isoformat(' '),))
                except sqlite3.Error as e:
                    self.logger.error('Historizing SQL Delete Old Data Error for events from %s: %s',
                                      event.SourceNode, e)

                self._conn.commit()

Hello!

I recently started working on OPC UA and Python, so I'm still trying to wrap my head around most things, so please, bear with me. This might be a pretty stupid question, but I just can't get it right, so I need to ask anyway - how do I get methods to work in my custom types?

Here's a short the example, based on the "server-minimal" example:

Whenever I call the method via Test Client, it always returns "BadNothingToDo". But I know this method works just fine! If I add it to an object, like the SmoothSample above, the method runs successfully when called by the client. But that can't be the only solution, right? I know I'm doing something wrong...

Please help me out!

Daniel

I finally tok some time to understand WhereClause stuff. WhereClause is clearly the correct way to filter by event type

Here is a first implementation to setup where clause from client when subscribing to events.

• this is not finished, we should have a recursive option to subscrive_events
• Need parsing of WhereClause on server, but this might be a bit complex...

Hey guys,

I am currently building a small program with which I use the opcua client to retrieve data from a controller and write it to a database.

The data retrieval is very slow, can you please tell me where my error is? The entire For grinding process takes almost 2 seconds.

thank you very much

`import sys
sys.path.insert(0, "..")


#import opcua und mysql libs
from opcua import Client
from opcua import ua
from opcua import *
import mysql.connector
#import Time libs
import datetime
import time
#import multiprocesses
import multiprocessing
from threading import Timer

import logging
logging.basicConfig()
#logging.basicConfig(level=logging.DEBUG)

#def worker():
#    """worker function"""
#    print('Worker')

def sec():
    """worker function"""
    sekunde = 0

    clientSec = Client("opc.tcp://"+login+ip+":"+port,timeout=10)
    try:
        clientSec.connect()
        connectionSec = mysql.connector.connect(host=host,database=db,port=dbPort,user=userdb,password=pwdb)
        cursorSec = connectionSec.cursor()
        # Get UA nodes in root
        root = clientSec.get_root_node()
        print("Client Sec connected")

        while 1:
            #time.sleep(1)
            t=time.time()
            while 1:
                if time.time()-t > 1:
                    print(time.time())
                    print('sec')
                    sekunde = sekunde +1
                    print(sekunde)
                    for P in range(PWU):
                        for S in range(STR):
                            for M in range(MDL):
                                
                                var = clientSec.get_node("ns=6;s=::AsGlobalPV:BCS.PWU["+str(P)+"].STR["+str(S)+"].MDL["+str(M)+"].iVoltTotal")
                                #Time = var.get_data_value().SourceTimestamp
                                iVoltTotal = round(var.get_value(),6)

                                var = clientSec.get_node("ns=6;s=::AsGlobalPV:BCS.PWU["+str(P)+"].STR["+str(S)+"].MDL["+str(M)+"].iCurrTotal")
                                #Time = var.get_data_value().SourceTimestamp
                                iCurrTotal = round(var.get_value(),6)

                                var = clientSec.get_node("ns=6;s=::AsGlobalPV:BCS.PWU["+str(P)+"].STR["+str(S)+"].MDL["+str(M)+"].iSoc")
                                #Time = var.get_data_value().SourceTimestamp
                                iSoc = round(var.get_value(),3)

                                Datum_Zeit = datetime.datetime.now()

                                
                                #cursorSec = connectionSec.cursor()
                                cursorSec.execute("INSERT INTO Pwu"+str(P)+"Strang"+str(S)+"Modul"+str(M)+" (Zeit,iVoltTotal,iCurrTotal,iSoc) VALUES (%s,%s,%s,%s)",(Datum_Zeit,iVoltTotal,iCurrTotal,iSoc))
                                #cursorSec.close()
                                connectionSec.commit()
                    t=time.time()                
    finally:
        clientSec.disconnect()
        connectionSec.close()


def min1():
    """worker function"""
    while 1:
        time.sleep(60)
        print('min1')
    

def min5():
    """worker function"""
    
    while 1:
        time.sleep(60*5)
        print('min5')

def sub():
    """worker function"""
    
    while 1:
        time.sleep(60)
        print('sub')


#Hauptframework
if __name__ == '__main__':
    jobs = []
    x=0
   #zugangsdaten
    
    #OpcUA
    ip      =   "10.96.7.10"
    port    =   "4840"
    login   =   "*****:****@"
    #MariaDB
    host    =   '10.96.7.245'
    db      =   'OpcUA'
    dbPort  =   '3307'
    userdb  =   '*****'
    pwdb    =   '*****'
    
    #Parameter
    PWU = 1   
    STR = 7
    MDL = 1
    #Variablen erstellen
    P = 0
    S = 0
    M = 0
    #maridB connect
    connection = mysql.connector.connect(host=host,database=db,port=dbPort,user=userdb,password=pwdb)
    print("Tabellen erzeugen")
    for P in range(PWU):
        for S in range (STR):
            for M in range (MDL):
                cursor = connection.cursor()
                cursor.execute("CREATE TABLE IF NOT EXISTS Pwu"+str(P)+"Strang"+str(S)+"Modul"+str(M)+"(id INT UNSIGNED PRIMARY KEY AUTO_INCREMENT,Zeit varchar(23),iTempMin0 float(4),iTempMin1 float(4),iTempMax0 float(4),iTempMax1 float(4),iTempCellAvg float(4),iVoltTotal float(6),iCurrTotal float(6),iSoc int(3))")
                #Alle Tabellen löschen:
                #cursor.execute("DROP TABLE Pwu"+str(P)+"Strang"+str(S)+"Modul"+str(M))
                cursor.close()
                print(P,S,M)
    
    #OpcUA Verbindung aufbauen
    client = Client("opc.tcp://"+login+ip+":"+port,timeout=10)
    #client = Client("opc.tcp://[email protected]:4840") #connect using a user
    try:
        client.connect()

        # Get UA nodes in root
        root = client.get_root_node()

        print("client connected")
        OPCtrue = client.get_node("ns=6;s=::AsGlobalPV:OPCtrue")

        #öffnen der einzelnen Prozesse
        for x in range(1):
            #Sekundne Prozess
            secjob = multiprocessing.Process(target=sec)
            jobs.append(secjob)
            secjob.start()
            #1 Minuten Prozess
            min1job = multiprocessing.Process(target=min1)
            jobs.append(min1job)
            min1job.start()
            #5 min Prozess
            min5job = multiprocessing.Process(target=min5)
            jobs.append(min5job)
            min5job.start()
            #Substription Prozess
            subjob = multiprocessing.Process(target=sub)
            jobs.append(subjob)
            subjob.start()
    finally:
        client.disconnect()
        connection.close()
        print("ENDE")    
`

Hi all,

I have a OPC DA server running on it. I have tested it on windows with client software and is working fine. I need make an application which will connect to this OPC DA server from linux. Is it possible to use this FreeOPCUA python for DA. Is this library compatible with OPC DA.

Thanks

Hello, I have install opcua but when I use this code by Visual Code (Python 3.8.2 32bit) from opcua import Client,ua I get the problem

No name 'ua' in module 'opcua' (no-name-in-module)

How can I fix it ?

Hello, recently I've noticed that under pretty high load the python-opcua periodically throws errors:

ERROR:opcua.server.binary_server_asyncio:Exception raised while parsing message from client, closing
Traceback (most recent call last):
  File "/home/user/_dev/python-opcua/opcua/server/binary_server_asyncio.py", line 85, in _process_data
    ret = self.processor.process(hdr, buf)
  File "/home/user/_dev/python-opcua/opcua/server/uaprocessor.py", line 73, in process
    msg = self._connection.receive_from_header_and_body(header, body)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 592, in receive_from_header_and_body
    return self._receive(chunk)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 623, in _receive
    self._check_incoming_chunk(msg)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 550, in _check_incoming_chunk
    self._security_token.ChannelId))
UaError: Wrong channel id 113, expected 180
('Cleanup client connection: ', ('127.0.0.1', 43833))

ERROR:opcua.server.binary_server_asyncio:Exception raised while parsing message from client, closing
Traceback (most recent call last):
  File "/home/user/_dev/python-opcua/opcua/server/binary_server_asyncio.py", line 85, in _process_data
    ret = self.processor.process(hdr, buf)
  File "/home/user/_dev/python-opcua/opcua/server/uaprocessor.py", line 73, in process
    msg = self._connection.receive_from_header_and_body(header, body)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 592, in receive_from_header_and_body
    return self._receive(chunk)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 623, in _receive
    self._check_incoming_chunk(msg)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 550, in _check_incoming_chunk
    self._security_token.ChannelId))
UaError: Wrong channel id 113, expected 181
('Cleanup client connection: ', ('127.0.0.1', 43834))

ERROR:opcua.server.binary_server_asyncio:Exception raised while parsing message from client, closing
Traceback (most recent call last):
  File "/home/user/_dev/python-opcua/opcua/server/binary_server_asyncio.py", line 85, in _process_data
    ret = self.processor.process(hdr, buf)
  File "/home/user/_dev/python-opcua/opcua/server/uaprocessor.py", line 73, in process
    msg = self._connection.receive_from_header_and_body(header, body)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 592, in receive_from_header_and_body
    return self._receive(chunk)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 623, in _receive
    self._check_incoming_chunk(msg)
  File "/home/user/_dev/python-opcua/opcua/ua/uaprotocol_hand.py", line 550, in _check_incoming_chunk
    self._security_token.ChannelId))
UaError: Wrong channel id 113, expected 182
('Cleanup client connection: ', ('127.0.0.1', 43835))

After each such error the server shuts down and restarts.

Currently I have around 140 datapoints (mostly double and int64) in 12 folders and they are updated inside python script every 0.5 seconds. The client (Prosys Java SDK based client) queries all the datapoints around each second. What is the issue and how to solve it? Thanks.

Dear all, I have an issue with the latest version of python-opcua. All versions up to 0.98.3 work fine, but with version 0.98.5 I get the following error:

Traceback (most recent call last):
  File "./client_example_minimal.py", line 23, in <module>
    var.set_value(True) # set node value using implicit data type
  File "/usr/lib/python3.7/site-packages/opcua/common/node.py", line 211, in set_value
    self.set_attribute(ua.AttributeIds.Value, datavalue)
  File "/usr/lib/python3.7/site-packages/opcua/common/node.py", line 257, in set_attribute
    result[0].check()
  File "/usr/lib/python3.7/site-packages/opcua/ua/uatypes.py", line 233, in check
    raise UaStatusCodeError(self.value)
opcua.ua.uaerrors._auto.BadWriteNotSupported: The server does not support writing the combination of value, status and timestamps provided.(BadWriteNotSupported)

This is the code that generates the error (taken by the client-minimal example):

#!/usr/bin/python3

import sys
sys.path.insert(0, "..")

from opcua import Client

if __name__ == "__main__":

    client = Client("opc.tcp://localhost:4840")
    try:
        client.connect()

        # get a specific node knowing its node id
        var = client.get_node("ns=4;s=MAIN.OutletTLSC.CloseCMD")
        #var = client.get_node("ns=4;s=MAIN.ConditionAutoClose.sGiveHour")

        #print(var)
        #var.get_data_value() # get value of node as a DataValue object
        #var.get_value() # get value of node as a python builtin

        #var.set_value(ua.Variant([23], ua.VariantType.Int64)) #set node value using explicit data type
        var.set_value(True) # set node value using implicit data type

    finally:
        client.disconnect()

I hope you can help me run the latest version of the software. Thank you.

Hi,

I am currently working with several companion specifications and trying to load them via server.import_xml(filename). Since the companion standards use the namespaceId 1 in their spec, the xml import always tries to import exactly in the defined namespace index that is given in the file instead of in the namespace index which must be generated by the server on startup.

As I read this it seems that the "correct" way is:

1. Load UA namespace (ns:0)
2. Create custom namespace (ns:1) -> server.register_namespace(uri)
3. Load XML File and translate the nodes given in the xml file to correct namespace (ns:2)
4. Load XML File and translate the nodes given in the xml file to correct namespace (ns:3)

The order of the Uri elements in <NameSpaceUris> should determine the file local namespace indexes:

    <NamespaceUris>
        <Uri>http://somemodel.org</Uri>
        <Uri>http://anothermodel.org/</Uri>
    </NamespaceUris>

Then in the XML file, references to ns=1;i=... must be translated to the the index of the first uri, i.e. http://somemodel.org while nodes reference to ns=2;i=... must be translated to the index of the second uri.

The index of the uris must be managed by the server, i.e. the order of loading models determines the namespace index.

Since I am a novice in OPC, I hope I described the scenario correct. Just wondering how other handle this scenario.

Bring back dump and load to do their original function and add methods for caching.

These serve different purposes. load and dump: just dump the entire address space to binary and then reload it cache: tries to speed up loading default address space, it doesn't support saving custom nodes and has other drawbacks; for example you can't delete nodes if using the cache

Also added isession.close() to the server stop code. This ensures all clean up is done, including the deletion of internal subscriptions (required for dumping address space)

Describe the bug
i've used the client-event example to subscribe to node to get the events, the only difference is that i didn't pass the event type when i use the subscribe_event

To Reproduce

sys.path.insert(0, "..")

try:
    from IPython import embed
except ImportError:
    import code

    def embed():
        vars = globals()
        vars.update(locals())
        shell = code.InteractiveConsole(vars)
        shell.interact()


from opcua import Client

from opcua.tools import uals

class SubHandler(object):

    """
    Subscription Handler. To receive events from server for a subscription
    data_change and event methods are called directly from receiving thread.
    Do not do expensive, slow or network operation there. Create another
    thread if you need to do such a thing
    """
    def event_notification(self, event):
        print("New event recived: ", event)


if __name__ == "__main__":

    client = Client("opc.tcp://192.168.0.5:8119/")
    try:
        client.connect()

        # Client has a few methods to get proxy to UA nodes that should always be in address space such as Root or Objects
        root = client.get_root_node()
        print("root node is: ", root)

        # Now getting a variable node using its browse path
        obj  = client.get_node('ns=2;s=Notification/Messages')
        print("Objects node is: ", obj)

        msclt = SubHandler()
        sub = client.create_subscription(100, msclt)
        handle = sub.subscribe_events(obj)

        embed()
        sub.unsubscribe(handle)
        sub.delete()
    finally:
        client.disconnect()

Expected behavior
wiev print New event recived: ... but getting nothing

Version
Python-Version:3.8.6
python-opcua Version (e.g. master branch, 0.9): 0.98.9

I am reading several nodes from opcua server. No issues reading single variable values using self.opcua.get_value(nodes) but when I trying to read history values I get an error "History Read Error: 'ExtensionObject' Object has no attribute 'DataValues'. Verified on UAExpert that the history data is available for the node of interest. Python version 3.10.2 on mac.

code:

starttime = "21.11.2022 08:09:09" starttime_dt_format = datetime.datetime.strptime(starttime,"%d.%m.%Y %H:%M:%S")
endtime = "21.11.2022 08:15:09" endtime_dt_format = datetime.datetime.strptime(endtime,"%d.%m.%Y %H:%M:%S")
thisnode = self.opcua.client.get_node("ns=2;s=OPCNode.TSInt32Random") data = await thisnode.read_raw_history(starttime=starttime_dt_format, endtime=endtime_dt_format, numvalues=20) #<-- This line returns error

I'm using python opcua server and client and I'm testing all the possible security features about authentication and communication. As the specs says, there is no implementation about security ID check, then even if I call the method set_security_ID, anonymous connections are still accepted. Is there a way to implement security ID check on a python opcua server ? Any suggestions ?

Describe the bug

[What I do]

1. Create an UA server with a method that can trigger an event

2. Create UA clientA which register the event.

3. Create clientB and use it to trigger event by call ua method.

[ISSUE]

• I found when I use another ua clientB to call UA_method_for_trigger_event, the event_notification in clientA will executed until UA_method_for_trigger_event complete.

• Is there any way to let client get notification immediately, while event_generator trigger signal

[Simple example code are as follows:]

[server.py]

    def UA_method_for_trigger_event():   # <====== Suppose this is an UA method in UA server.
        event_generator.trigger(message="")
        time.sleep(30)

[clientA.py]

    class UASubscriber(object):
        def __init__(self):
           pass 

        def event_notification(self, event):
            # Will execute until  'UA_method_for_trigger_event ' in server complete   <====== ISSUE
            data = event.get_event_props_as_fields_dict()
            print("data = ", data)

Expected behavior

Is there any way to let client get notification while event_generator.trigger event_generator.trigger singal

Version

python 3.8

I succeeded in connecting Siemens CPU through OPC-UA communication. (Attach the code below) However, after a certain period of time, it is terminated after an exception occurs as shown below. Anyone who knows why please help me

########################### My Code from opcua import Client import logging import time from datetime import datetime

url = "opc.tcp://10.27.176.101:4840"

client = Client(url) client.set_user("OpcUaClient") client.set_password("12345678") client.connect()

while True: ____try: ________ rst = client.get_node("ns=2;s=/Channel/Spindle/driveLoad[1]")
________ print(rst.get_value()) ________print('#==================#') ________time.sleep(0.05) ____except(TimeoutError): ________print('-------------------------------------timeout') ________ print(str(TimeoutError)
________continue

############################### exception information ERROR:opcua.client.ua_client.Socket:Protocol Error Traceback (most recent call last): File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 101, in _run self._receive() File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 112, in _receive msg = self._connection.receive_from_socket(self._socket) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 363, in receive_from_socket return self.receive_from_header_and_body(header, ua.utils.Buffer(body)) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 328, in receive_from_header_and_body self._check_sym_header(security_header) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 276, in _check_sym_header self.next_security_token.TokenId)) opcua.ua.uaerrors._base.UaError: Invalid security token id 6, expected 5 or 0 ERROR:opcua.client.ua_client.Socket:Protocol Error Traceback (most recent call last): File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 101, in _run self._receive() File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 112, in _receive msg = self._connection.receive_from_socket(self._socket) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 363, in receive_from_socket return self.receive_from_header_and_body(header, ua.utils.Buffer(body)) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 335, in receive_from_header_and_body return self._receive(chunk) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 366, in _receive self._check_incoming_chunk(msg) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\connection.py", line 311, in _check_incoming_chunk .format(self._peer_sequence_number, num)) opcua.ua.uaerrors._base.UaError: Wrong sequence 3061 -> 3063 (server bug or replay attack) Traceback (most recent call last): File "test.py", line 45, in Exception in thread Thread-2: Traceback (most recent call last): File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\threading.py", line 916, in _bootstrap_inner self.run() File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\client.py", line 68, in run val = server_state.get_value() File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 153, in get_value result = self.get_data_value() File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 162, in get_data_value return self.get_attribute(ua.AttributeIds.Value) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 273, in get_attribute result = self.server.read(params) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 337, in read data = self._uasocket.send_request(request) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 83, in send_request data = future.result(self.timeout) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\concurrent\futures_base.py", line 434, in result raise TimeoutError() concurrent.futures._base.TimeoutError logWrite(str(rst.get_value()))

File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 153, in get_value result = self.get_data_value() File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 162, in get_data_value return self.get_attribute(ua.AttributeIds.Value) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\common\node.py", line 273, in get_attribute result = self.server.read(params) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 337, in read data = self._uasocket.send_request(request) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\site-packages\opcua\client\ua_client.py", line 83, in send_request data = future.result(self.timeout) File "C:\Users\jm0902.kim\AppData\Local\Programs\Python\Python36\lib\concurrent\futures_base.py", line 434, in result raise TimeoutError() concurrent.futures._base.TimeoutError