nova list crashes on startup

[Ken Sheedlo]

I'm running OSX Mavericks. I just installed novaclient via a git clone + easy_install. This is the stack trace I get when I try to list my servers:

┌─[ken][Kens-MacBook-Pro][2.1.2][~]
└─▪ nova list --status active
Traceback (most recent call last):
  File "/usr/local/bin/nova", line 6, in <module>
    from novaclient.shell import main
  File "/Library/Python/2.7/site-packages/novaclient/shell.py", line 47, in <module>
    from novaclient import client
  File "/Library/Python/2.7/site-packages/novaclient/client.py", line 33, in <module>
    from keystoneclient import adapter
  File "/Library/Python/2.7/site-packages/keystoneclient/__init__.py", line 37, in <module>
    __version__ = pbr.version.VersionInfo('python-keystoneclient').version_string()
  File "/Library/Python/2.7/site-packages/pbr/version.py", line 78, in version_string
    for part in self.release_string().split('.'):
  File "/Library/Python/2.7/site-packages/pbr/version.py", line 70, in release_string
    self.release = self._get_version_from_pkg_resources()
  File "/Library/Python/2.7/site-packages/pbr/version.py", line 62, in _get_version_from_pkg_resources
    return packaging.get_version(self.package)
  File "/Library/Python/2.7/site-packages/pbr/packaging.py", line 870, in get_version
    raise Exception("Versioning for this project requires either an sdist"
Exception: Versioning for this project requires either an sdist tarball, or access to an upstream git repository. Are you sure that git is installed?

[b.sudhakoushik (b-sudhakoushik)]

Is .git folder present in the python-novaclient folder ?

[Ken Sheedlo (ken-sheedlo)]

I found a workaround by installing both python-novaclient and pbr manually using setup.py install.

[b.sudhakoushik (b-sudhakoushik)]

one more work around....you can just give git init in the python-novaclient where you ahve the error. it will work :-)

[melanie witt (melwitt)]

I'm able to reproduce the problem on OS X 10.9.4 using the instructions for installing client via pip:

http://docs.openstack.org/user-guide/content/install_clients.html

[melanie witt (melwitt)]

Clients should use pkg_resources instead of pbr to get package version.

[melanie witt (melwitt)]

This is happening because currently pbr looks to read the PKG-INFO file and if it fails, it tries to get the version information from git. In packages that use package metadata 2.0, there is a METADATA file instead of a PKG-INFO file and pbr doesn't know yet to look for it. Then the fallback to git will fail if pbr can't find a way to query it.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/121751

[Doug Hellmann (doug-hellmann)]

melwitt reports that the problem occurs with setuptools version 0.6c11 on precise and 0.6c12dev-r88846 on OS X

[Robert Collins (lifeless)]

BTW I completely disagree that clients should use pkg_resources. While we read version metadata from multiple sources in pbr, the version a client exposes at $client.version or $client.__version__ *must* match, which means either a complete copy of the pbr logic (including git checks), or using pbr.

[melanie witt (melwitt)]

I learned from chatting with lifeless and dstufft that the PKG-INFO vs METADATA file isn't related to package metadata version at all -- it's two different packaging formats described in PEP 0376 [1] and PEP 0427 [2].

[1] http://legacy.python.org/dev/peps/pep-0376/#how-distributions-are-installed
[2] http://legacy.python.org/dev/peps/pep-0427/#the-dist-info-directory

[melanie witt (melwitt)]

To correct my earlier comment, the way in which clients query package version is still up for debate!

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/121751
Committed: https://git.openstack.org/cgit/openstack-dev/pbr/commit/?id=eb7238725ed1837bd69d957f711087a45b82b8ab
Submitter: Jenkins
Branch: master

commit eb7238725ed1837bd69d957f711087a45b82b8ab
Author: melanie witt <email address hidden>
Date: Tue Sep 16 04:53:36 2014 +0000

    Support reading versions from wheels

    This change adds the ability for pbr to read the package version from
    the METADATA file as well as the PKG-INFO file. The PKG-INFO file
    is present for sdist packages but for wheel packages (PEP 427),
    there is a METADATA file instead of a PKG-INFO file.

    Closes-Bug: #1369179
    Change-Id: I2fe52c846fd88d37a4ab78de87eec9defce1ba0a

[Stanislaw Pitucha (viraptor-gmail)]

So is this not going to make any close release? None of the nova clients > 2.17 (up to the current 2.20) are installable via pip.

In practice `pip install python-novaclient` fails for new users with only reference to this bug being via google.