Set "y"/"Series" such that a single object/payload can draw multiple data points

[joepavitt]

Description

With the incoming 0.7.0 release, you'll be able to define series, x and y for a chart, which tells it which data points/values to render onto the chart given an incoming payload, e.g.

msg.payload = [{
    time: '2023-10-30',
    a: 3,
    b: 7
}, {
    time: '2023-10-31',
    a: 4,
    b: 5
}]

We can set the key for the x-axis to time and the key for the y-axis to a on the ui-chart in order to render {'2023-10-30', 3}, {'2023-10-31', 4}.

If we want to plot two data points/lines onto the same chart, we would still need to run a function node, and split these data points into messages like:

msg = [{
    topic: 'A',
    payload: {
        time: '2023-10-30',
        value: 3
    }
}, {
    topic: 'B',
    payload: {
        time: '2023-10-30',
        value: 7
    }
}, ...]

This feels excessive and messy. Our objective with ui-chart is everything should be as low code as possible.

As such, I propose that instead, we provide the functionality to set series to be something like multiple, and then provide an additional type for the y-axis TypedInput that is JSON, such that you can pass a list: ["a", "b"] and it will then plot two data points from a single piece of data.

Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate

[joepavitt]

Actually, having series option for JSON, and then defining the criteria there makes more sense. If JSON type is chosen, then the y axis option should hide.