EXAMPLE - turning a node's status 'on' and 'off'
The following example will show how to turn a node's status on and off. This example uses an inject node to start the process connected to a function node that has a deliberate error (a variable is undefined) connected to a debug node (which never activates because of the error.)
A 'catch' node catches the error and pass it to a function node that sets the function node's status to a red dot with the text of 'ERROR'. The function node is attached to a debug node which displays the error message.
The 'catch' node is also connected to a delay node (a 3 second delay) which is connected to a change node that sets msg.topic to 'clear'. The change node is connected to the function node that has the status displaying.
The key is in the function node. It checks node.topic to see if it is "clear" - if it is, it clears node.status and returns without sending a msg otherwise it sets the node status and msg.topic anad goes on it's merry way.
// check to see if status should be cleared
if (msg.topic == "clear") {
// YES so clear status and exit without sending a msg.
node.status({});
return;
} else {
// NO, set status, msg.topis and return msg
node.status({fill:"red",shape:"dot",text:"ERROR"});
msg.topic = "Logging flow";
}
return msg;
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