Ok, rather than like my previous attempt (may be deleted now) here is the problem: Two RPIs. They both ping the Gateway and another "real" IP address. They both report their results and publish them to MQTT. The messages range from: OnLine, OffLine. (And if that RPI is powered down/turned off …

If you need to make decisions based on the current state of two variables then feed them both into a Join node set to Key/Value pair mode, identified by topic, wait for 2 messages and send on every new message after that, so you then get one message with both values in it each time either of them ch…

[image] Colin: feed them both into a Join node set to Key/Value pair mode Thanks, but I can't find that setting in the join node. All I can see is: Automatic, Manual and Reduce sequence.

Having selected Manual, what other options do you see?

Yeah, ok....... But reading the info on the node it kind of says it is to be used with the split node. It joins the two strings. I am missing how I can use this to assign weight to which message is shown. Could you please expand on how this node is supposed to get two messages and "select" one …

Don't use string mode, use key/value mode (as I said, go back and read the original mail again). Once you have both of them you can look at them and send whatever you want.

I can't see: [image] Colin: Join node set to Key/Value pair mode a key/value object ? [image] Colin: so you then get one message with both values in it each time either of them changes. Then you can perform whatever logic you want on the result. That's the part where I am stuck. P…

key/value object is one of the options. Do you mean you don't even know what you want to do, never mind how to do it? Can't help much there I am afraid.

Here is a basic example of what I am wanting to do: Machine 1 sending: Machine1 modem online Machine 2 sending: Machine2 modem online Great. For now, let's say I want Machine1's message to be weighted and sent. Then the messages change to: Machine1 modem offline Machine2 modem online Machin…

Maybe you need something like https://flows.nodered.org/node/node-red-contrib-nools to establish some rules & priorities.

Get the join working then you can easily do that in a function node.

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Help with logic filtering of message

General

Trying_to_learn 17 March 2019 09:57 7

I can't see:

a key/value object ?

That's the part where I am stuck.

Preforming the logic.

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Help with logic filtering of message

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