I found this flow helpfull and it is growing over time. It has a function library, global variables, some usefull cron nodes, a central http request, a telegram output etc.... [image] [{"id":"b263e6b23d8eb759","type":"tab","label":"Sytem Services","disabled":false,"info":"","env":[]},{"id":"82252…

Is it possible to call context.global.rel_pressure() from a change node?

You can store functions in a global/flow context variable; function helloWorld(){ return 'Hello World' } global.set("myCustomFunction",helloWorld) which you can call from any function node like; const h = global.get("myCustomFunction") node.warn(h()) // "Hello World"

Yes @juntiedt has explained, slightly differently, how to call such a function from a function node. What I asked though was if there is a way to call it from a change node. (eg using the "global...." output type) Perhaps I should explain why I ask. There has been some discussion around formatti…

You can if you use a JSONata expression (I used flow context rather than global) $flowContext('formatLabel')(payload, 2, "£ ", ' million') [{"id":"a7916d0894793fe5","type":"function","z":"fe7296cf2a5f7fba","name":"Set Flow Variable","func":"const input = msg.payload\n\nflow.set('formatLabel', ru…

That looks promising thanks @Buckskin . Only now there are three different syntaxes to define the function; I need to try and work out if they are actually different or just rewording. [image] Buckskin: Sorry just realised that this was all covered in another thread ( Suffix for text output ) .…

Don’t forget, if you do that then global context HAS to be in memory, as functions are non-serialisable, which is why we do not encourage that pattern.

Out of curiosity, what would you suggest? I think I'm not the only one, dealing with functions/classes reusability issue. I've tried passing functions via global.context, but only recently started storing them into a single function. I've tried creating a subflow with all functions, call it befor…

@KarolisL since this is a low code platform I would suggest the low code approach with a smidge of functional programming purity... Put each reusable function into single function node with a link-in to the left and a link-out-return on the right and use link-call to call than graphically. You can …

I agree completely. I am using this method since long for my central HTTP-request. The reason doing it was that I had to many http-request on one RPI causing network traffic jam. The link call solved the problem.

Don't want to hijack this topic, but did you mean something like this? [{"id":"b769cfec2072262d","type":"function","z":"0e97ec53d28db263","name":"function select","func":"if(msg.topic === \"sum\") {\n msg.target = \"sum_in\"\n msg.initVal = msg.payload\n return msg \n}\nif(msg.topic === \"…

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zenofmud 30 December 2025 14:13 23

You could also use this node:

It offers lots of information.

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First flow on all my RPIs

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