pbr version conflict

[sivel]

The current version of python-novaclient has a dependency on pbr specified by pbr>=0.11,<2.0. Unfortunately with the release of pbr 1.0.0 the requirement pulls in 1.0.0 (or 1.0.1) which is incompatible with the pbr version required for:

oslo.i18n
python-keystoneclient
oslo.serialization
oslo.utils

This results in the following error:

ERROR (ContextualVersionConflict): (pbr 1.0.1 (/Users/matt/python_venvs/tmp-33f824993191418f/lib/python2.7/site-packages), Requirement.parse('pbr!=0.7,<1.0,>=0.6'), set(['oslo.i18n', 'python-keystoneclient', 'oslo.serialization', 'oslo.utils']))

Downgrading to pbr==0.11.0 resolves the problem.

[melanie witt (melwitt)]

I'm not able to reproduce the problem when I 'pip install python-novaclient' (version 2.25.0). Could you please describe how you encountered this?

[sivel (sivel)]

That is odd. I was able to get it to happen reliably yesterday while using a temporary virtual environment with only installing python-novaclient. Unfortunately I deactivated it and it was deleted.

However, under a slightly new scenario I can still get it to happen.

If I have an auth_plugin that registers itself via the openstack.client.auth_plugin entrypoint. The moment that ep.load() is called from novaclient.auth_plugin.discover_auth_systems I get the above message.

Even if the class that the entry point references does nothing such as:

class TestAuthPlugin(object):
    pass

[sivel (sivel)]

The origination of this report is initially from https://github.com/rackspace/pyrax/issues/561

With 'rackspace-auth-openstack' installed is when I was able to reproduce it today. Removing it indicated that being the issue. But I have replicated it with the above sample that performs no function.

[melanie witt (melwitt)]

Thanks for that info. How are you installing the rackspace plugin? So far, my concern is whoever is packaging the auth plugin -- it sounds like maybe they need to release a new version that meshes with the current novaclient version.

[Nicolas Bär (nicolas-baer)]

I encountered this problem as well. It installs novaclient without any issue, but then when you use it, it will throw the above error message.

For the following requirements pip will install pbr 1.0.1
novaclient requirements [1]: pbr>=0.11,<2.0
oslo.config requirements [2]: pbr>=0.6,!=0.7,<1.0

[1]: https://github.com/openstack/python-novaclient/blob/2.25.0/requirements.txt
[2]: https://github.com/openstack/oslo.config/blob/1.11.0/requirements.txt

[sivel (sivel)]

As previously mentioned, I can cause this bug to happen with a auth plugin that actually does nothing:

https://gist.github.com/sivel/4eab70746b747affa9b3

In fact, if I comment out the line using setuptools.find_packages in setup.py and install no python file at all, the entry point will still cause this error to happen. Such as installing using a setup.py that looks like:

https://gist.github.com/sivel/cb98f8d98849a030e970

As long as you have an entrypoint for openstack.client.auth_plugin or novaclient.extension it will cause this error as soon as ep.load() is called.

[Bob Ball (bob-ball)]

Confirmed that it happens with me too:
"virtualenv /tmp/env; . /tmp/env/bin/activate/; pip install rackspace-novaclient; nova list"

The error I Get is http://paste.openstack.org/show/239540/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/186111

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/186111
Committed: https://git.openstack.org/cgit/openstack/python-novaclient/commit/?id=e649cea843b8453d268da8ea74ea180f513d5ea3
Submitter: Jenkins
Branch: master

commit e649cea843b8453d268da8ea74ea180f513d5ea3
Author: Doug Hellmann <email address hidden>
Date: Wed May 27 18:08:02 2015 +0000

    Do not check requirements when loading entry points

    Update the calls to pkg_resources to avoid forcing a requirements check
    when the plugins are being loaded.

    There are 2 versions of the entry point API in different releases of
    setuptools. In one version, the require keyword argument can be passed
    to load(). In the other, separate methods resolve() and require() need
    to be used. This change updates the mock and fake objects to support
    either, since the fakes are subclasses of the EntryPoint class in
    pkg_resources.

    It would be better to replace the calls to pkg_resources with stevedore,
    which provides a more stable API, abstracts away this difference, and
    provides an API for creating test managers directly. That change would
    have required more extensive updates to the test suite, though, and
    since I'm not as familiar with this code base as others will be, I will
    leave those changes for someone else.

    Change-Id: I2a9aeb53ccad04c7fa687f25340306b84218f9ff
    Partial-bug: #1457100

[melanie witt (melwitt)]

Marking as Fix Committed because it solves the problem. There's some desire to keep novaclient's dependencies to a minimum, but either way, I think changing to use stevedore can be considered a future improvement.

[Keisuke Yamamoto (keisuk-yamamoto)]

pbr 1.0.1 conflict occurred by designate install.

# python setup.py develop
...
Installed /var/lib/designate
Processing dependencies for designate==2015.2.0.dev83
error: Installed distribution pbr 1.0.1 conflicts with requirement pbr>=0.6,!=0.7,<1.0

Install pbr v0.11 in advance.
Designate installing is Finished.

# pip install pbr==0.11
# python setup.py develop
...
Using /var/lib/designate/.venv/lib/python2.7/site-packages
Finished processing dependencies for designate==2015.2.0.dev83