Connection events
Get the status (the status action) gives the state of the connection now. You send a message, and you get the answer.
The Endpoint Events node (OpcUa-Endpoint-Events) sends a message each time the connection changes: connecting, connected, reconnecting, retry, failed and disconnected. It also warns before the user certificate expires. It needs no input message, and it works with every licence. Connect it to the same endpoint as the Endpoint Control node. The help of the events node describes the payload.
The reason of an event tells why, for people. Three reasons do not change:
| Reason | When |
|---|---|
switching to new settings | a Connect or a Reset replaces an open session |
switch failed, previous settings restored | the new settings failed, and the previous settings are in use again |
disconnected on request | a Disconnect closed the session |
Use event and state in the logic of your flow. Do not test a reason: its text can change, except for the three reasons in the table. For example, after a failed switch, the reason of a failed or disconnected event is an error message.
Use both nodes:
- The Endpoint Events node tells a dashboard at once when a Connect ends, or when a server stops.
- Get the status gives the facts of the session when a user asks for them.