Browse Path Prefixed Integers: Are they assigned by NodeClass type?

[dldltn]

Hey folks,

I'm trying to understand the Object/Variable structure of a server so that I can get node IDs by their browse path in a python function (which I'm already doing but I want to try to minimise issues with my code).

I've noticed that the BrowseName of an Object is often in the following hierarchical structure:

• 0:Objects
  • 2:Server
  • 2:Channel
    • 2:SomeObject
      • 2:Variable1
      • 2:Variable2
• 0:Types
  • 0:DataTypes
  • 0:EventTypes

And, I'm using the following code to get my node IDs:

root = client.get_root_node()
node1 = root.get_child(["0:Objects", "2:Channel", "2:SomeObject", "2:Variable1"])

Is it possible to do away with the prefixed integers altogether? For example:

node1 = root.get_child("/Objects/Channel/SomeObject/Variable")

If not, then how is the prefixed integer (i.e., the 0 or 2) assigned? Is it a matter of server setup?

I can't determine a relationship between the NodeClass (Object or Variable etc.) but I have noticed that the Node ID formats are different. For example, a Node ID of i=84 has its BrowseName prefixed with a "0:". Yet a Node ID of "ns=2;i=6" has a BrowseName prefixed with a "2:".

Do node classes have different types? If so, is it possible to get the node type? Then, I can just throw in an if statement based on the node type to handle it appropriately.

EDIT: I asked far too many questions here. I've struck through the extra questions, and for now I'll read up more on namespaces.

[swamper123]

Hey ho,

this prefixed integers are the namespaceindex of your node. They are neccesarry to identify the correct namespace of your nodes.

https://documentation.unified-automation.com/uasdkcpp/1.7.4/html/L2UaAdrSpaceConceptNamespaces.html

[dldltn]

Thank you. I'll take the time to read the link you provided and learn more about namespaces.