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FreeOpcUa / python-opcua

LGPL Pure Python OPC-UA Client and Server
http://freeopcua.github.io/
GNU Lesser General Public License v3.0
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Filtering / Searching for nodes #431

Open jvibo opened 7 years ago

jvibo commented 7 years ago

Hello all, I’m looking for a possibility to filter nodes by an expression. E.g. a list with all nodes that are Integers. I think there is some feature with events and where conditions, but I need to filter all nodes not only the event nodes. My idea was to get a node, or more, not knowing the nodeID oder the browse path.

oroulet commented 7 years ago

On server side you can go through the entire addresspace dict. On client side I do not think ua defines such a possibility. If anybody knows one, let me know.

jvibo commented 7 years ago

How do you achieve this? And is it implemented in python opc-ua yet? The UA Specifications chapter 9 (Alarms and Conditions) section D.3 says something about namespace and filtering.

oroulet commented 7 years ago

you can filter events yes. you will need to look at code of subscribe_events and look how the filter is generated. everything should be implemented but I do not remember exactly what is possible and not