st2actionrunner doesn't respect system user when doing private repo pack installs

SUMMARY

I have a special user on my st2 machines that has permissions for installing packs. This is also the same user listed in the st2.conf file as the system user (replacing stanley). When doing an install from a private repo the st2actionrunner is continues to run as root and therefore none of the ssh keys are setup for this.

STACKSTORM VERSION

Paste the output of st2 --version:

st2 3.5.0, on Python 3.6.8

OS, environment, install method

HA cluster (non-k8s): 2 app nodes and 1 controller

Steps to reproduce the problem

As a non-root user try to install a package from a private git repo

Expected Results

The package to install using the system user specified in the st2.conf file so it would use that user's keys.

Actual Results

st2actionrunner runs as the root user instead of the system user specified in st2.conf.

Looking at source the install only happens as the current user that is running the pid. In this case st2actionrunner runs as the root user only while all the other services run as the system user specified in st2.conf.

Thinking of ways to work around this one without adding keys to the root user.

Thanks!

Start by tracing the st2actionrunner private-repository pack-install path and how it reads the system user from st2.conf. Reproduce the install as a non-root user on the described HA setup, then verify that installation uses the configured user's identity and SSH keys rather than root.