[AMBARI-12912] Python Wrapper Can Choose Two Different Python Versions

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.1.2
• Assignee: Andrew Onischuk
• Reporter: Andrew Onischuk
• Created: 28/Aug/15 09:25
• Updated: 28/Aug/15 12:03
• Resolved: 28/Aug/15 09:28

Description

Environments that have 2 different versions of Python cause problems when
running agent code in memory. This was encountered on an Ambari 1.6 upgrade to
2.1 where Python 2.6 had all of the site-packages, but python2.7 was being
chosen by the agent.

The `ambari-python-wrap` script is the problem. Consider the code:

export PYTHONPATH=/usr/lib/python2.6/site-packages:/usr/lib/python2.6/site-packages/ambari_commons:$PYTHONPATH

1. reset settings
   unset PYTHON

1. checking for preferable python versions
   if [ -a /usr/bin/python2.7 ] && [ -z "$PYTHON" ]; then
   PYTHON=/usr/bin/python2.7
   fi

if [ -a /usr/bin/python2.6 ] && [ -z "$PYTHON" ]; then
PYTHON=/usr/bin/python2.6
fi

This is hardcoding the `PYTHONPATH` to use `site-packages` from `python2.6`.
But then, it choose the Python 2.7 executor as the wrapper. This means that
the agents will be running as Python 2.7 and executing scripts with a Python
2.6 site-package.

The observed problem was that the "rpm" and "yum" packages could not be loaded
by agent code on an INSTALL command since these packages were part of the 2.6
site-packages and not 2.7 site-packages.

Issue Links

• links to: ReviewBoard