- like a rocketeer, but for versions!
- https://github.com/warner/python-versioneer
- Brian Warner
- License: Public Domain
- Compatible With: python2.6, 2.7, 3.2, 3.3, 3.4, 3.5, and pypy
- ![Latest Version] (https://pypip.in/version/versioneer/badge.svg?style=flat)
- ![Build Status] (https://travis-ci.org/warner/python-versioneer.png?branch=master)
This is a tool for managing a recorded version number in distutils-based python projects. The goal is to remove the tedious and error-prone "update the embedded version string" step from your release process. Making a new release should be as easy as recording a new tag in your version-control system, and maybe making new tarballs.
pip install versioneerto somewhere to your $PATH- add a
[versioneer]section to your setup.cfg (see below) - run
versioneer installin your source tree, commit the results
Source trees come from a variety of places:
- a version-control system checkout (mostly used by developers)
- a nightly tarball, produced by build automation
- a snapshot tarball, produced by a web-based VCS browser, like github's "tarball from tag" feature
- a release tarball, produced by "setup.py sdist", distributed through PyPI
Within each source tree, the version identifier (either a string or a number, this tool is format-agnostic) can come from a variety of places:
- ask the VCS tool itself, e.g. "git describe" (for checkouts), which knows about recent "tags" and an absolute revision-id
- the name of the directory into which the tarball was unpacked
- an expanded VCS keyword (
$Id$ , etc) - a
_version.pycreated by some earlier build step
For released software, the version identifier is closely related to a VCS
tag. Some projects use tag names that include more than just the version
string (e.g. "myproject-1.2" instead of just "1.2"), in which case the tool
needs to strip the tag prefix to extract the version identifier. For
unreleased software (between tags), the version identifier should provide
enough information to help developers recreate the same tree, while also
giving them an idea of roughly how old the tree is (after version 1.2, before
version 1.3). Many VCS systems can report a description that captures this,
for example git describe --tags --dirty --always reports things like
"0.7-1-g574ab98-dirty" to indicate that the checkout is one revision past the
0.7 tag, has a unique revision id of "574ab98", and is "dirty" (it has
uncommitted changes.
The version identifier is used for multiple purposes:
- to allow the module to self-identify its version:
myproject.__version__ - to choose a name and prefix for a 'setup.py sdist' tarball
Versioneer works by adding a special _version.py file into your source
tree, where your __init__.py can import it. This _version.py knows how to
dynamically ask the VCS tool for version information at import time.
_version.py also contains $Revision$ markers, and the installation
process marks _version.py to have this marker rewritten with a tag name
during the git archive command. As a result, generated tarballs will
contain enough information to get the proper version.
To allow setup.py to compute a version too, a versioneer.py is added to
the top level of your source tree, next to setup.py and the setup.cfg
that configures it. This overrides several distutils/setuptools commands to
compute the version when invoked, and changes setup.py build and setup.py sdist to replace _version.py with a small static file that contains just
the generated version data.
See INSTALL.md for detailed installation instructions.
Code which uses Versioneer can learn about its version string at runtime by
importing _version from your main __init__.py file and running the
get_versions() function. From the "outside" (e.g. in setup.py), you can
import the top-level versioneer.py and run get_versions().
Both functions return a dictionary with different flavors of version information:
-
['version']: A condensed version string, rendered using the selected style. This is the most commonly used value for the project's version string. The default "pep440" style yields strings like0.11,0.11+2.g1076c97, or0.11+2.g1076c97.dirty. See the "Styles" section below for alternative styles. -
['full-revisionid']: detailed revision identifier. For Git, this is the full SHA1 commit id, e.g. "1076c978a8d3cfc70f408fe5974aa6c092c949ac". -
['date']: Date and time of the latestHEADcommit. For Git, it is the commit date in ISO 8601 format. This will be None if the date is not available. -
['dirty']: a boolean, True if the tree has uncommitted changes. Note that this is only accurate if run in a VCS checkout, otherwise it is likely to be False or None -
['error']: if the version string could not be computed, this will be set to a string describing the problem, otherwise it will be None. It may be useful to throw an exception in setup.py if this is set, to avoid e.g. creating tarballs with a version string of "unknown".
Some variants are more useful than others. Including full-revisionid in a
bug report should allow developers to reconstruct the exact code being tested
(or indicate the presence of local changes that should be shared with the
developers). version is suitable for display in an "about" box or a CLI
--version output: it can be easily compared against release notes and lists
of bugs fixed in various releases.
The installer adds the following text to your __init__.py to place a basic
version in YOURPROJECT.__version__:
from ._version import get_versions
__version__ = get_versions()['version']
del get_versions
The setup.cfg style= configuration controls how the VCS information is
rendered into a version string.
The default style, "pep440", produces a PEP440-compliant string, equal to the
un-prefixed tag name for actual releases, and containing an additional "local
version" section with more detail for in-between builds. For Git, this is
TAG[+DISTANCE.gHEX[.dirty]] , using information from git describe --tags --dirty --always. For example "0.11+2.g1076c97.dirty" indicates that the
tree is like the "1076c97" commit but has uncommitted changes (".dirty"), and
that this commit is two revisions ("+2") beyond the "0.11" tag. For released
software (exactly equal to a known tag), the identifier will only contain the
stripped tag, e.g. "0.11".
Other styles are available. See details.md in the Versioneer source tree for descriptions.
Versioneer tries to avoid fatal errors: if something goes wrong, it will tend
to return a version of "0+unknown". To investigate the problem, run setup.py version, which will run the version-lookup code in a verbose mode, and will
display the full contents of get_versions() (including the error string,
which may help identify what went wrong).
Some situations are known to cause problems for Versioneer. This details the most significant ones. More can be found on Github issues page.
Versioneer has limited support for source trees in which setup.py is not in
the root directory (e.g. setup.py and .git/ are not siblings). The are
two common reasons why setup.py might not be in the root:
- Source trees which contain multiple subprojects, such as
Buildbot, which contains both
"master" and "slave" subprojects, each with their own
setup.py,setup.cfg, andtox.ini. Projects like these produce multiple PyPI distributions (and upload multiple independently-installable tarballs). - Source trees whose main purpose is to contain a C library, but which also provide bindings to Python (and perhaps other langauges) in subdirectories.
Versioneer will look for .git in parent directories, and most operations
should get the right version string. However pip and setuptools have bugs
and implementation details which frequently cause pip install . from a
subproject directory to fail to find a correct version string (so it usually
defaults to 0+unknown).
pip install --editable . should work correctly. setup.py install might
work too.
Pip-8.1.1 is known to have this problem, but hopefully it will get fixed in some later version.
Bug #38 is tracking this issue. The discussion in PR #61 describes the issue from the Versioneer side in more detail. pip PR#3176 and pip PR#3615 contain work to improve pip to let Versioneer work correctly.
Versioneer-0.16 and earlier only looked for a .git directory next to the
setup.cfg, so subprojects were completely unsupported with those releases.
setup.py develop and pip install --editable . allow you to install a
project into a virtualenv once, then continue editing the source code (and
test) without re-installing after every change.
"Entry-point scripts" (setup(entry_points={"console_scripts": ..})) are a
convenient way to specify executable scripts that should be installed along
with the python package.
These both work as expected when using modern setuptools. When using
setuptools-18.5 or earlier, however, certain operations will cause
pkg_resources.DistributionNotFound errors when running the entrypoint
script, which must be resolved by re-installing the package. This happens
when the install happens with one version, then the egg_info data is
regenerated while a different version is checked out. Many setup.py commands
cause egg_info to be rebuilt (including sdist, wheel, and installing into
a different virtualenv), so this can be surprising.
Bug #83 describes this one, but upgrading to a newer version of setuptools should probably resolve it.
While Versioneer works (and is continually tested) with both Python 2 and Python 3, it is not entirely consistent with bytes-vs-unicode distinctions. Newer releases probably generate unicode version strings on py2. It's not clear that this is wrong, but it may be surprising for applications when then write these strings to a network connection or include them in bytes-oriented APIs like cryptographic checksums.
Bug #71 investigates this question.
To upgrade your project to a new release of Versioneer, do the following:
- install the new Versioneer (
pip install -U versioneeror equivalent) - edit
setup.cfg, if necessary, to include any new configuration settings indicated by the release notes. See UPGRADING for details. - re-run
versioneer installin your source tree, to replaceSRC/_version.py - commit any changed files
This tool is designed to make it easily extended to other version-control
systems: all VCS-specific components are in separate directories like
src/git/ . The top-level versioneer.py script is assembled from these
components by running make-versioneer.py . In the future, make-versioneer.py
will take a VCS name as an argument, and will construct a version of
versioneer.py that is specific to the given VCS. It might also take the
configuration arguments that are currently provided manually during
installation by editing setup.py . Alternatively, it might go the other
direction and include code from all supported VCS systems, reducing the
number of intermediate scripts.
To make Versioneer easier to embed, all its code is dedicated to the public
domain. The _version.py that it creates is also in the public domain.
Specifically, both are released under the Creative Commons "Public Domain
Dedication" license (CC0-1.0), as described in
https://creativecommons.org/publicdomain/zero/1.0/ .