Support importing in pyodide

Problem

I am a contributor to and user of HoloViz Panel. Panel works with Ipywidgets. Panel can now convert panel apps to webassembly.

BUT it seems I cannot include ipywidgets in those converted apps.

For example if I open the pyodide console and try to

import micropip
micropip.install("ipywidgets")

it fails

....
    raise ValueError(
ValueError: Can't find a pure Python 3 wheel for 'tornado>=6.1'.
See: https://pyodide.org/en/stable/usage/faq.html#micropip-can-t-find-a-pure-python-wheel
You can use `micropip.install(..., keep_going=True)`to get a list of all packages with missing wheels.

Proposed Solution

Support importing ipywidgets in pyodide.

Additional context

In the end I would like to be able to panel convert apps like

"""
The purpose of this app is to demonstrate that Panel works with the tools you know and love
❤️, including ipysheet.
"""
import ipysheet
import panel as pn

from awesome_panel import config

config.extension("ipywidgets", url="lib_ipysheet")

ACCENT = config.ACCENT


def get_component(accent_base_color=ACCENT):
    """Returns an ipysheet app"""
    slider = pn.widgets.FloatSlider(value=10, start=0, end=100)
    sheet = ipysheet.sheet()

    ipysheet.cell(1, 1, "Input")
    cell3 = ipysheet.cell(1, 2, 42.0)
    ipysheet.cell(2, 1, "Output")
    cell_sum = ipysheet.cell(2, 2, 52.0, read_only=True, background_color=accent_base_color)

    @pn.depends(slider, cell3, watch=True)
    def calculate(value1, value2):
        cell_sum.value = value1 + value2

    return pn.Column(slider, sheet)


component = get_component()
pn.panel(component, height=700, sizing_mode="stretch_both").servable()

and provide a Basic Ipywidgets App example at https://www.awesome-panel.org/sharing

Originally opened here https://github.com/QuantStack/ipysheet/issues/236.

[martinRenou]

Sorry I read the thread too fast.

So yeah as other said removing the ipykernel dependency or providing a shim for it would be what you need.

[maartenbreddels]

https://github.com/widgetti/solara/blob/ce456e0fed4e0dde6df486d830eca9044b25eb71/solara/server/static/solara_bootstrap.py was my quick iterate and hack attempt. Maybe that’s helpful.