===============================
 Notes for Package maintainers
===============================

If you are maintaining packages of software that uses *pbr*, there are some
features you probably want to be aware of that can make your life easier.
They are exposed by environment variables, so adding them to rules or spec
files should be fairly easy.

Versioning
----------

*pbr*, when run in a git repo, derives the version of a package from the
git tags. When run in a tarball with a proper egg-info dir, it will happily
pull the version from that. So for the most part, the package maintainers
shouldn't need to care. However, if you are doing something like keeping a
git repo with the sources and the packaging intermixed and it's causing pbr
to get confused about whether its in its own git repo or not, you can set
``PBR_VERSION``:

::

  export PBR_VERSION=1.2.3

and all version calculation logic will be completely skipped and the supplied
version will be considered absolute.

Distribution version numbers
----------------------------

*pbr* will automatically calculate upstream version numbers for *dpkg* and
*rpm* using systems. Releases are easy (and obvious). When packaging
pre-releases though things get more complex. Firstly, semver does not provide
for any sort order between pre-releases and development snapshots, so it can be
complex (perhaps intractable) to package both into one repository - we
recommend with either packaging pre-release releases (alpha/beta/rc's) or dev
snapshots but not both.  Secondly, as pre-releases and snapshots have the same
major/minor/patch version as the version they lead up to, but have to sort
before it, we cannot map their version naturally into the rpm version
namespace: instead we represent their versions as versions of the release
before.

Dependencies
------------

As of 1.0.0 *pbr* doesn't alter the dependency behaviour of *setuptools*.

Older versions would invoke *pip* internally under some circumstances and
required the environment variable ``SKIP_PIP_INSTALL`` to be set to prevent
that. Since 1.0.0 we now document that dependencies should be installed before
installing a *pbr* using package. We don't support easy install, but neither
do we interfere with it today. If you observe easy install being triggered when
building a binary package, then you've probably missed one or more package
requirements.

.. important::

   We reserve the right to disable easy install via *pbr* in future, since we
   don't want to debug or support the interactions that can occur when using
   it.

.. _packaging-tarballs:

Tarballs
--------

*pbr* includes everything in a source tarball that is in the original *git*
repository. This can again cause havoc if a package maintainer is doing fancy
things with combined *git* repos, and is generating a source tarball using
``python setup.py sdist`` from that repo. If that is the workflow the packager
is using, setting ``SKIP_GIT_SDIST``:

::

  export SKIP_GIT_SDIST=1

will cause all logic around using git to find the files that should be in the
source tarball to be skipped. Beware though, that because *pbr* packages
automatically find all of the files, most of them do not have a complete
``MANIFEST.in`` file, so its possible that a tarball produced in that way will
be missing files.

.. _packaging-authors-changelog:

AUTHORS and ChangeLog
---------------------

*pbr* generates ``AUTHORS`` and ``ChangeLog`` files from *git* information.
This can cause problem in distro packaging if package maintainer is using *git*
repository for packaging source. If that is the case setting
``SKIP_GENERATE_AUTHORS``

::

   export SKIP_GENERATE_AUTHORS=1

will cause logic around generating ``AUTHORS`` using *git* information to be
skipped. Similarly setting ``SKIP_WRITE_GIT_CHANGELOG``

::

   export SKIP_WRITE_GIT_CHANGELOG=1

will cause logic around generating ``ChangeLog`` file using *git*
information to be skipped.

.. _packaging-releasenotes:

Release Notes
-------------

*pbr* generates a release notes file, typically called ``RELEASENOTES.rst``,
if `reno`_ is present and configured. You may wish to disable this
functionality. If that is the case setting ``SKIP_GENERATE_RENO``

::

   export SKIP_GENERATE_RENO

will disable this feature.

.. _reno: https://docs.openstack.org/reno/latest/
