Figure factory broken in release 4.7.0

[cliffckerr]

Describe the bug

Related to #1111, import plotly.figure_factory fails with the most recent Plotly release (4.7) without a helpful error message.

To reproduce

First noticed with

conda create -n plotly_test python=3.7.7
conda activate plotly_test
pip install plotly_express
python
>>> import plotly.figure_factory

(which worked until this morning's release), but also reproducible via:

conda create -n plotly_test python=3.7.7
conda activate plotly_test
pip install numpy==1.18.4 plotly==4.7.0
python
>>> import plotly.figure_factory

Expected behavior

It works, or at least gives a helpful error message.

Actual behavior

>>> import plotly.figure_factory
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/software/anaconda3/envs/plotly_test/lib/python3.7/site-packages/plotly/figure_factory/__init__.py", line 14, in <module>
    from plotly.figure_factory._2d_density import create_2d_density
  File "/software/anaconda3/envs/plotly_test/lib/python3.7/site-packages/plotly/figure_factory/_2d_density.py", line 8, in <module>
    from plotly.graph_objs import graph_objs
  File "/software/anaconda3/envs/plotly_test/lib/python3.7/site-packages/plotly/graph_objs/graph_objs.py", line 1, in <module>
    from plotly.graph_objs import *
  File "/software/anaconda3/envs/plotly_test/lib/python3.7/site-packages/plotly/graph_objs/__init__.py", line 290, in __getattr__
    return orig_getattr(import_name)
  File "/software/anaconda3/envs/plotly_test/lib/python3.7/site-packages/_plotly_utils/importers.py", line 41, in __getattr__
    name=import_name, __name__=parent_name
AttributeError: module 'plotly.graph_objs' has no attribute 'FigureWidget'

Workaround

Manually install ipywidgets (e.g., pip install ipywidgets plotly_express works).

Suggested solution

Add ipywidgets back to the plotly_express requirements, and make an ipywidgets error message similar to the one that exists if you try to use figure_factory without having numpy installed.

Platform:

• OS: Ubuntu 18.04
• Python: 3.7.7 (observed on Python 3.8 as well, but not on Python 3.6)

[jonmmease]

Thanks for the report @cliffckerr, and thanks for pointing out the workaround of installing ipywidgets.

The underlying issue here is with the from plotly.graph_objs import * statement. FigureWidget shows up in __all__ even when ipywidgets is not installed, so it is picked up by *.

For performance reasons, we don't want to attempt to import ipywidgets when plotly.py is imported. One option might be to return a dummy class in place of FigureWidget when ipywidgets is not installed. This dummy class would raise a missing dependency exception in the constructor.

[emmanuelle]

we could also fix this by changing the imports in _2d_density.py which are a bit weird (why from plotly.graph_objs import graph_objs` ?). I'm surprised our tests did not catch this...

[rysktky]

Is this a same sort of issue?
I can't use subplots unless explicitly import it.

>>> import sys
>>> import plotly

>>> sys.version
'3.7.7 (tags/v3.7.7:d7c567b08f, Mar 10 2020, 10:41:24) [MSC v.1900 64 bit (AMD64)]'
>>> plotly.__version__
'4.7.0'

>>> plotly.subplots
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python37\lib\site-packages\_plotly_utils\importers.py", line 41, in __getattr__
    name=import_name, __name__=parent_name
AttributeError: module 'plotly' has no attribute 'subplots'

>>> from plotly import subplots
>>> subplots
<module 'plotly.subplots' from 'C:\\Python37\\lib\\site-packages\\plotly\\subplots.py'>
>>> subplots.make_subplots
<function make_subplots at 0x0000023F70199E58>
>>>
>>> plotly.subplots
<module 'plotly.subplots' from 'C:\\Python37\\lib\\site-packages\\plotly\\subplots.py'>
>>>

[jonmmease]

Proposed fix in #2445. @emmanuelle would you have time to take a look?

[cliffckerr]

Closed by #2445

[nicolaskruchten]

@cliffckerr this is now released as part of 4.7.1!

[cliffckerr]

Super, thanks @nicolaskruchten !

[leo-smi]

Is this a same sort of issue? I can't use subplots unless explicitly import it.

>>> import sys
>>> import plotly

>>> sys.version
'3.7.7 (tags/v3.7.7:d7c567b08f, Mar 10 2020, 10:41:24) [MSC v.1900 64 bit (AMD64)]'
>>> plotly.__version__
'4.7.0'

>>> plotly.subplots
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python37\lib\site-packages\_plotly_utils\importers.py", line 41, in __getattr__
    name=import_name, __name__=parent_name
AttributeError: module 'plotly' has no attribute 'subplots'

>>> from plotly import subplots
>>> subplots
<module 'plotly.subplots' from 'C:\\Python37\\lib\\site-packages\\plotly\\subplots.py'>
>>> subplots.make_subplots
<function make_subplots at 0x0000023F70199E58>
>>>
>>> plotly.subplots
<module 'plotly.subplots' from 'C:\\Python37\\lib\\site-packages\\plotly\\subplots.py'>
>>>

this error still occur on plotly 5.5.0, the only way to use it is import like this:

from plotly.subplots import make_subplots

windows 10
python 3.10

[nicolaskruchten]

@leo-smi this is intentional, yes.