Stuck using config node multiple times

Developing Nodes
1

Hey there! I'm stuck understanding one simple mechanism. Please enlighten me.

I use a config node and as far as I learned from the docs, I get the content with RED.nodes.getNode. So I do:

Let me describe the situation with the option "bool". In JS, I do:

module.exports = function(RED) {
    function configNode(config) {
        RED.nodes.createNode(this,config)
		this.config = config
	}
    RED.nodes.registerType("mytemplate-config",configNode);
	
	function workingNode(config) {
		RED.nodes.createNode(this,config)
		let parms = RED.nodes.getNode(config.config)
		...
	RED.nodes.registerType("mytemplate",workingNode);
}
...

Which gives me the console output:

configNode {
  id: 'f476dc6e65b0a93d',
  type: 'mytemplate-config',
  z: undefined,
  g: undefined,
  _closeCallbacks: [],
  _inputCallback: null,
  _inputCallbacks: null,
  name: 'myparms',
  wires: [],
  _wireCount: 0,
  send: [Function: NOOP_SEND],
  config: {
    id: 'f476dc6e65b0a93d',
    type: 'mytemplate-config',
    name: 'myparms',
    valueType: 'bool',
    value: 'true',
    _users: [ '01a83f7c216f97b8', 'd2ef1c167664e574' ]
  }
}

One parameter field config.value is a typedInput allowing ["bool","num","str"]. I learned that "bool" and "num" are also stored as strings and I have to convert it first. Now in JS I do:

...
if (parms.config.valueType === "bool") {
	parms.config.value = parms.config.value === "true"
}
...

Resulting in:

valueType: 'bool',
value: true,

Great. But when calling the node a second time, it fails. If I add a console.log before and after conversion, I see that the second node, before conversion, holds the value from the conversion of the first node.

BEFORE CONVERSION
configNode {
  ...
  config: {
    ...
    valueType: 'bool',
    value: 'true',
    ...
  }
}
AFTER CONVERSION
configNode {
  ...
  config: {
    ...
    valueType: 'bool',
    value: true,
    ...
  }
}
BEFORE CONVERSION
configNode {
  ...
  config: {
    ...
    valueType: 'bool',
    value: true,
    ...
  }
}
AFTER CONVERSION
configNode {
  ...
  config: {
    ...
    valueType: 'bool',
    value: false,
    ...
  }
}

Find the complete code here: GitHub - danube/template

Doh... kinda hard to explain, hope you got it. Now may you guide me to the right path please... Regards! Thomas

2

Hi Thomas, you could take the easy way out and change your test to:

...
if (parms.config.valueType === "bool") {
	parms.config.value = ( parms.config.value === "true" || parms.config.value === true )
}
...

Doubtless there are more elegant ways but that seems simple, and direct if a little brutal. :slight_smile:

3

Hi and thanks for taking time!

There is just one major thing I don't understand. I call the same node twice with the same configuration node(!). In the code I create a copy of the config with

let parms = RED.nodes.getNode(config.config)

and then do the manipulation:

parms.config.value = parms.config.value === "true"

This works for the first call of the node, where the type is being converted from STRING 'true' to BOOL true. But on the second call, I see a BOOL before conversion. Remember: Same code, same config node! For some weird reason it seems to me that the second node call holds the value converted by the first call.

4

If you modify params then you are modifying the config node and any other users of that node will see the change.

It would be cleaner to to any property validation/cleanup in the config node itself so all consumers of it will benefit and don't need to do it themselves.

5

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