"config_dict" UnboundLocalError after upgrade to Plotly 3.8.1

[SigmaX]

After upgrading from 3.7.1 to 3.8.1 (as installed via pip/PyPI), simple plots break with UnboundLocalError: local variable 'config_dict' referenced before assignment.

Minimum working example:

import plotly.graph_objs as go

go.Figure()

Expected behavior: a Figure should be returned.

Figure({
    'data': [], 'layout': {}
})

I'm running macOS and Python 3.7.0. Downgrading to plotly 3.7.1 is a workaround: sudo pip3 install plotly=3.7.1.

Stack trace:

---------------------------------------------------------------------------
UnboundLocalError                         Traceback (most recent call last)
<ipython-input-1-0c49f1f32fec> in <module>()
      1 import plotly.graph_objs as go
      2 
----> 3 go.Figure()

/usr/local/lib/python3.7/site-packages/plotly/graph_objs/_figure.py in __init__(self, data, layout, frames, skip_invalid)
    501             is invalid AND skip_invalid is False
    502         """
--> 503         super(Figure, self).__init__(data, layout, frames, skip_invalid)
    504 
    505     def add_area(

/usr/local/lib/python3.7/site-packages/plotly/basedatatypes.py in __init__(self, data, layout_plotly, frames, skip_invalid)
    196         # options are compatible with FigureWidget.
    197         from plotly.offline.offline import _get_jconfig
--> 198         self._config = _get_jconfig(None)
    199 
    200         # Frames

/usr/local/lib/python3.7/site-packages/plotly/offline/offline.py in _get_jconfig(config)
    160         clean_config = {}
    161 
--> 162     plotly_platform_url = plotly.tools.get_config_plotly_server_url()
    163 
    164     clean_config['plotlyServerURL'] = plotly_platform_url

/usr/local/lib/python3.7/site-packages/plotly/tools.py in get_config_plotly_server_url()
   1286             data = {}
   1287 
-> 1288     return config_dict.get('plotly_domain', default_server_url)
   1289 
   1290 

UnboundLocalError: local variable 'config_dict' referenced before assignment

I observe the same behavior with more involved go.Figure() calls, such as the following:

import plotly.graph_objs as go
import numpy as np

x = np.arange(0, 1, 0.03)
y = np.arange(0, 1, 0.03)
xx, yy = np.meshgrid(x, y)
f = lambda v: np.array(v[0])**2 + np.array(v[1])**2

@np.vectorize
def v_fun(x, y):
    return f([x, y])

z = v_fun(xx, yy)
trace = [go.Surface(x=x, y=y, z=z, showscale=False)]
fig = go.Figure(data=trace,
                layout=go.Layout(
                    scene={"xaxis": {'title': "", "tickfont": {"size": 10}, 'type': "linear"},
                           "yaxis": {"title": "", "tickfont": {"size": 10},
                                     "tickangle": 1},
                           "zaxis": {'title': "Fitness", "tickfont": {"size": 10}},
                           "aspectratio": {'x': 2.0, 'y': 2.0, 'z': 1.0}
                           }
                ))

[jonmmease]

Thanks a lot for the report @SigmaX, it looks like this error would crop up when the ~/.plotly/.config file is not found or not loaded successfully. #1551 should take care of it.

[jonmmease]

Hi @SigmaX, could you try out the 3.9.0 release candidate and check whether this takes care of the issue for you? installation instructions at https://github.com/plotly/plotly.py/blob/release_3.9.0/README.md#installation.

Thanks!

[SigmaX]

Works like a charm. Thanks so much for the lightning-fast fix, @jonmmease!