Add compatibility for ipywidgets>=8

[philippjfr]

• Fixes Required updates for ipywidgets 8.0  #10
• Fixes Wrong widget protocol version #32
• Fixes IpyCanvas raising errors #44

[philippjfr]

@mattpap Could you review and release version 1.3 when you get a chance?

We can then follow up with another PR for bokeh 3.0 compatibility.

[philippjfr]

Might need some more testing.

[mattpap]

@philippjfr, do you intend any further changes to this PR, or can I proceed with merging and releasing a new version?

[philippjfr]

Let's proceed. Seemed to work well for me.

[mattpap]

The Python side of this still needs updating. With ipywidgets 8.0.2 I'm getting:

export SRC_DIR=/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/test_tmp
Traceback (most recent call last):
  File "/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/test_tmp/run_test.py", line 2, in <module>
import: 'ipywidgets_bokeh'
    import ipywidgets_bokeh
  File "/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehol/lib/python3.11/site-packages/ipywidgets_bokeh/__init__.py", line 1, in <module>
    from .widget import IPyWidget
  File "/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehol/lib/python3.11/site-packages/ipywidgets_bokeh/widget.py", line 13, in <module>
    from .kernel import kernel
  File "/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehol/lib/python3.11/site-packages/ipywidgets_bokeh/kernel.py", line 142, in <module>
    kernel = BokehKernel.instance()
             ^^^^^^^^^^^^^^^^^^^^^^
  File "/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehol/lib/python3.11/site-packages/traitlets/config/configurable.py", line 551, in instance
    inst = cls(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^
  File "/home/mateusz/conda/envs/bk_py310/conda-bld/ipywidgets_bokeh_1669112794075/_test_env_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehold_placehol/lib/python3.11/site-packages/ipywidgets_bokeh/kernel.py", line 128, in __init__
    self.comm_manager = CommManager(parent=self, kernel=self)
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: CommManager.__init__() got an unexpected keyword argument 'parent'

I already published npm and pip ipywidgets_bokeh 1.3.0 before realizing this.

[mattpap]

Also, do we expect ipytwidgets_bokeh working with both ipywidgets 7.x and 8.x or only 8.x?

[mattpap]

Or perhaps this is the issue with ipykernel's CommManger in version 6.18. I couldn't reproduce, because I upgraded ipywidgets but not ipykernel, but conda had most recent version in the build environment.

[mattpap]

All packages are published now.

[philippjfr]

Damn, taking a look now. As far as I could tell it was working with both 7.x and 8.x.

[philippjfr]

So those errors are coming from ipykernel 6.18 which was released yesterday and split out Comm and CommManager into a separate package and changed the baseclasses (removing LoggingConfigurable as a baseclass which is what accepted parent). That release seems to have broken half the ecosystem and they already yanked that release from PyPI. They'll hopefully restore that.

[mattpap]

@philippjfr, I removed the defunct version like this ipykernel 6.*,!=6.18.0 (in meta.yaml) and published 1.3.0.

[philippjfr]

Perfect, thanks!