BaseDirectory: fix race condition for os.makedirs()

[cjp256]

In the case of parallel usage, there is race between when the
directory is checked and created. To prevent this race, use
exist_ok=True which is supported in python 3.2+.

https://docs.python.org/3/library/os.html#os.makedirs

Signed-off-by: Chris Patterson [email protected]

[cjp256]

Since python 2.7 is EOL, is it desired to continue to support it? If so, we can replace with a try/except block. But I'd hope anyone still on python2.7 has their dependencies pinned down by this point ;) If not, I can PR to drop 2.7 support.

[takluyver]

I'm OK with dropping Python 2.7 at this point. Can you update the CI config and the setup.py (both the classifiers list & adding a python_requires field).

[zbentley]

Is there anything I can do to help get this merged? This issue occasionally affects us in production.

Is the only required change the setup.py/CI configuration?

[takluyver]

Yup, I think those are the only required changes. Alternatively, you could make this Python 2 compatible if that's easier (try/except to catch OSError, ignore the exception if e.errno == errno.EEXIST) - whichever is easier.

[zbentley]

Will this do it? #18