[Starlingx-discuss] Python2 -> Python3

[Saul Wold]

Folks,

There has been some discussion about what it means for StarlingX to be 
Python3. I would like to clarify my thoughts and propose a direction 
that will work without creating too much work and risk.

The current proposal seems to be to completely convert the base 
CentOS7.6 system level python to use python3, this carries a high risk 
factor as changing out all system-level python code could have a cascade 
effect on system functionality and additional dependencies. While 
python2 support is due to be depreciated in January from Python.org, 
RHEL will continue to support python2 for RHEL/CentOS7 as they have to 
give their customers Long Term support.

A better solution would be to build python3 and the associated 
requirements from the existing RHEL EPEL (Extra Packages for Enterprise 
Linux) Source RPMs repo and install them into the ISO. This version 
correctly installs in a segregated directory tree.

Another option would be to delay the actual python2 conversion to 
StarlingX 4.0, the OpenStack Train release will still support python2.

There is still work that is needed beyond the conversion of the python 
code itself to things like RPM specfiles data and other source code 
(such as, C code that has #includes of python2.7). It's not clear to me 
how much functional testing with python3 has occurred for the flock 
beyond what Dean has started with devstack.



   Sau!