How to store a selected layer in a variable or an object that could be used later to execute actions on the layer

Photoshop
1

Hi, I’m new to UXP and have been looking for a way to store a layer or a layer’s id with a specific parameter/attribute (related to the actions that need to be executed. For example a ‘resize’ or ‘move’) somewhere that would be persistent and linked to the specific document to use later to execute an action on the layer.
this should work on the same layer in a duplicated document.
Something like assigning a variable to a layer in photoshop’s Data Sets.
My other question: Is there a way to access the variables that we set on layers (image > variables > define…) in photoshop’s datasets?
something like this below

    const app = require("photoshop").app;
    const appCore = require('photoshop').core
    const doc = app.activeDocument

    const setVariable = async () => {
        if (doc.activeLayers.length >= -1){
            doc.activeLayers.forEach(async (layer) => {
                window.localStorage.setItem(layer.id)
            })
        }else{
            await appCore.showAlert({ message: 'Please select layers to assign a variable to'})
        }
    }

However local storage is not linked to a document.

Thanks

2

The only way you’re going to be able to attach persistent data to a file is by writing it to the file’s metadata.
Just stringify it and either write to an existing metadata field or create a custom one.
I’m pretty sure that document and layer ids are not persistent though and will change every time the document is closed/re-opened (or possibly for each Photoshop session) so this might be a moot exercise without doing something like renaming the layer and storing that as your reference id instead.

3

AFAIK layer IDs are persistent. Document ID is not

4

Thank you Timothy for your reply. That sounds like the perfect solution, I will look up how to write an entry to the file’s metadata. would you be able to provide a quick example?

As Karmalakas said, I tested the layer IDs and they’re persistent, doc IDs change but if data is stored in the file’s metadata, then I assume it will be present in the duplicated document.

5

I’ve not personally messed with metadata since CEP, but here’s a link to some pretty detailed forums posts on the subject: