How to use OPCUA Client with nsuri

[sasauz]

Hallo,

I'm trying to subscribe to OPC-UA node with nsuri. It is loock licke: ns=3;s=OPC_UA.nsuri=http://opcuatest.com/something/;s=level1.level2.l3.l4

My Quell-Code looks like:

var = client.get_node("ns=3;s=OPC_UA.nsuri=http://opcuatest.com/something/;s=level1.level2.l3.l4") print(var) v = var.get_value() print(v)

This is the output

Node(StringNodeId(ns=3;s=level1.level2.l3.l4)) Traceback (most recent call last): File "opcuaclient.py", line 43, in v = var.get_value() # get value of node as a python builtin File "/home/user/.local/lib/python2.7/site-packages/opcua/common/node.py", line 153, in get_value result = self.get_data_value() File "/home/user/.local/lib/python2.7/site-packages/opcua/common/node.py", line 162, in get_data_value return self.get_attribute(ua.AttributeIds.Value) File "/home/user/.local/lib/python2.7/site-packages/opcua/common/node.py", line 274, in get_attribute result[0].StatusCode.check() File "/home/user/.local/lib/python2.7/site-packages/opcua/ua/uatypes.py", line 231, in check raise UaStatusCodeError(self.value) opcua.ua.uaerrors._auto.BadNodeIdInvalid: The syntax of the node id is not valid.(BadNodeIdInvalid)

get_node-Method loose "s=OPC_UA.nsuri=http://opcuatest.com/something/".

Can some one help me?

UPDATE; I have also try to use get_namespace_index

uri = "http://opcuatest.com/something/" idx = client.get_namespace_index(uri)

but it also doesn't work:

return uries.index(uri) ValueError: 'http://opcuatest.com/something/' is not in list

[AndreasHeine]

According to: http://documentation.unified-automation.com/uasdkhp/1.0.0/html/_l2_ua_node_ids.html

What is the "Identifier Type" of this variable you want to subscribe?

[sasauz]

It is String:

[AndreasHeine]

from above: var = client.get_node("ns=3;s=OPC_UA.nsuri=http://opcuatest.com/something/;s=level1.level2.l3.l4")

have you tried to use: var = client.get_node("ns=3;s=level1.level2.l3.l4")

it looks strange to me if i see two times "s=" => "ns=3;s=xxx;s=yyy"

this looks like a namespaceuri: http://opcuatest.com/something/ and this like the identifier: level1.level2.l3.l4

what system is it i have never seen such strange node id... sorry

[sasauz]

"s=" => "ns=3;s=xxx;s=yyy" it is also new to me. It's look like a namespace uri with identifier inside of identifier

But what is really interesting, it is possible to read data with Softing OPC-UA Client, but not with other Clients/Libraries

have you tried to use: var = client.get_node("ns=3;s=level1.level2.l3.l4")

yes, I also try so, but it also doesn't work

Is it possible to read data with freeOpcUa via display name or with browse name?

[oroulet]

Our library crashes for sure due to the extra ; inside your string urn. You will need to prove this is acceptable by spec before changing this

[fcaspani01]

Is there any update??

I have the same problem but I get the value by navigate the nodes with get_children function but it doesn't work with get_node function.

[AndreasHeine]

this is not a valid nodeid!

[AndreasHeine]

@fcaspani01

ns=<namespaceIndex>;<identifiertype>=<identifier>

see https://documentation.unified-automation.com/uasdkhp/1.4.1/html/_l2_ua_node_ids.html

[AndreasHeine]

there are cases of an expanded nodeids

nsu=<namespaceUri>;<identifiertype>=<identifier>

for which you need to read the namespacearray from server and resolve to

ns=<namespaceIndex>;<identifiertype>=<identifier>