Activate virtualenv in disk-image-create

Because we're still fundamentally a python program calling a
shell-script, there's some oddities like not having the virtualenv
bin/ in the $PATH if we call disk-image-create directly.

We can detect this, however, and activate the virtualenv before we
fork the disk-image-create shell script so everything "just works".

See also nodepool change I0537cbf167bb18edf26f84ac269cbd9c8a1ea6a2

Change-Id: Ibfea6cf6a6fd0c7f1e468d501c61ae0b58992042
Ian Wienand 6 years ago
parent 7d5afecfd9
commit 04208e7c79
  1. 32

@ -19,7 +19,39 @@ import sys
import diskimage_builder.paths
# borrowed from
def running_under_virtualenv():
"""Return True if we're running inside a virtualenv, False otherwise."""
if hasattr(sys, 'real_prefix'):
return True
elif sys.prefix != getattr(sys, "base_prefix", sys.prefix):
return True
return False
def activate_venv():
if running_under_virtualenv():
activate_this = os.path.join(sys.prefix, "bin", "")
execfile(activate_this, dict(__file__=activate_this))
def main():
# If we are called directly from a venv install
# (/path/venv/bin/disk-image-create) then nothing has added the
# virtualenv bin/ dir to $PATH. the exec'd script below will be
# unable to find call other dib tools like dib-run-parts.
# One solution is to say that you should only ever run
# disk-image-create in a shell that has already sourced
# bin/ (all this really does is add /path/venv/bin to
# $PATH). That's not a great interface as resulting errors will
# be very non-obvious.
# We can detect if we are running in a virtualenv and use
# virtualenv's "" script to activate it ourselves
# before we call the script. This ensures we have the path setting
environ = os.environ
# pre-seed some paths for the shell script