6.0.0 release issue for Shiny for Python apps: "Please install anywidget to use the FigureWidget class"

[igi-chris]

I am building a shiny for python dashboard. On the latest deployment plotly updated from 5.24.1 -> 6.0.0 and the plots no longer render with the error: "Please install anywidget to use the FigureWidget class". For now I have worked around the issue by specifying the version in my requirements.txt file plotly==5.24.1

[igi-chris]

For a reproducible example you can use one of the template apps provided by shiny that uses plotly e.g. the dashboard-tips template. Once you have shiny installed you can download the template with shiny create --template dashboard-tips --mode express --github posit-dev/py-shiny-templates, set up a virtual env and install the dependencies in the downloaded requirements.txt file.

Using plotly 6.0.0 the plots fail as shown in the screenshot below:

However, if you downgrade plotly to 5.24.1 the dashboard renders as expected:

Here is the full traceback (from the 6.0.0 version):

Traceback (most recent call last):
File "d:\code\spikes\shiny_experiments.venv\Lib\site-packages\shiny\session_session.py", line 1450, in output_obs
value = await renderer.render()
^^^^^^^^^^^^^^^^^^^^^^^
File "d:\code\spikes\shiny_experiments.venv\Lib\site-packages\shinywidgets_render_widget_base.py", line 87, in render
widget = as_widget(value)
^^^^^^^^^^^^^^^^
File "d:\code\spikes\shiny_experiments.venv\Lib\site-packages\shinywidgets_as_widget.py", line 26, in as_widget
res = _as_widget(x)
^^^^^^^^^^^^^
File "d:\code\spikes\shiny_experiments.venv\Lib\site-packages\shinywidgets_as_widget.py", line 75, in as_widget_plotly
return go.FigureWidget(x.data, x.layout) # type: ignore
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "d:\code\spikes\shiny_experiments.venv\Lib\site-packages\plotly\missing_anywidget.py", line 13, in init
raise ImportError("Please install anywidget to use the FigureWidget class")
ImportError: Please install anywidget to use the FigureWidget class

[ndrezn]

@marthacryan I see that anywidget is only in requires-optional: https://github.com/plotly/plotly.py/blob/master/packages/python/plotly/requires-optional.txt#L51 Should it go into a requires-jupyter or elsewhere so that it's easier to know what to install?

This is a UX recommendation; the fix for this issue @igi-chris might be for Posit to update their templates.

You can also:

pip install anywidget

manually in your environment to resolve the issue.

[marthacryan]

I agree! One thing I'll note though is that this is identical to the behavior before the 6.0.0 release except that ipywidgets was substituted for anywidget as the package required. We should at the very least update the wording of the error to say pip install anywidget for clarity.