Read current OPC-UA node values
POST/opc-ua/nodes/values
Reads the current values of the given node ids from the OPC-UA client. Each node is read at the server it is registered on, so the ids may span several servers.
A node whose value could not be used - the server reports a bad status, or its server could not be reached - is omitted from the answer rather than returned with a null value, so it cannot be mistaken for a node that has no value. An uncertain status is not a failure: such a value is returned.
Note that an OPC-UA node id is only unique per server. If one of the given ids exists on more than one server of the tenant, the request cannot say which one is meant and is refused with 409 rather than answered from either.
Request
Responses
- 200
- 400
- 401
- 403
- 409
- 503
- 504
- default
The values that could be read - one entry per node, in no guaranteed order. The list may be shorter than the request: a node whose value the server refused or whose server could not be reached is left out, which is what tells it apart from a node that simply carries no value. An empty list therefore means "nothing readable right now", not "unknown nodes".
No node id was given.
Unauthorized — the bearer token is missing, expired or invalid, or carries no role. Errors raised by the security aspects contain an ErrorDto body; requests rejected by the security filter chain may have an empty body.
Forbidden — the authenticated user lacks the required role or access rights.
One of the given node ids exists on more than one OPC-UA server of the tenant, so the server it is meant for cannot be derived from the id.
None of the OPC-UA servers the request needs is connected. Connections are established in the background, so this can occur shortly after a restart and the request is worth repeating.
The OPC-UA client did not answer within the configured read timeout. A slow OPC-UA server can cause this while the client is still probing.
the default error response