Allow user to set plotly directory as environment variable

[synzhu]

It would be very convenient if there were a way to set the plotly directory in the PLOTLY_DIR environment variable, or default to ~/.plotly if the variable is not set. It can be easily done by changing line 4 here: https://github.com/plotly/plotly.py/blob/master/plotly/files.py
to the following:

PLOTLY_DIR = os.environ.get("PLOTLY_DIR", os.path.join(os.path.expanduser("~"), ".plotly"))

Then, to specify a custom plotly directory when running a script which uses the plotly module, we can do PLOTLY_DIR=/path/to/plotly_dir python script_that_uses_plotly.py

[ladhani]

Also a big headacke getting plotly running with Microsoft IIS on Windows Server using CGI binding with python.exe. As home directory will be pointing to some subfolder under windows system folder. So a no-no for writing .plotly and .testing subfolders!!!

I made the following ugly change in files.py:

---

import os

file structure

#PLOTLY_DIR = os.path.join(os.path.expanduser("~"), ".plotly")
#CREDENTIALS_FILE = os.path.join(PLOTLY_DIR, ".credentials")
#CONFIG_FILE = os.path.join(PLOTLY_DIR, ".config")

#TEST_DIR = os.path.join(os.path.expanduser("~"), ".test")
#TEST_FILE = os.path.join(PLOTLY_DIR, ".permission_test")

#Changed by Al-Noor

PLOTLY_DIR = ".plotly"
CREDENTIALS_FILE = os.path.join(PLOTLY_DIR, ".credentials")
CONFIG_FILE = os.path.join(PLOTLY_DIR, ".config")

TEST_DIR = ".plotly_test"
TEST_FILE = os.path.join(PLOTLY_DIR, ".permission_test")

So now ,plotly folders are made in the Web folder where IIS User has permission to write/read.

And now I can use plotly on Microsoft 2016 server with IIS and Python via CGI.

But it would be better to have a more clean solution, I think!
(local accounts now get the ,plotly folders in each of their local directory where they run py with plotly.

I will submit this issue / feature request to plotly.

[jonmmease]

Done in #1195. If present, the PLOTLY_DIR environment variable is taken as the path to the plotly.py configuration directory. If not present, the path remains ~/.plotly.

I know it's been a while, but thanks for the suggestion @simon-zhu!