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zest.releaser 6.4

Software releasing made easy and repeatable

Package releasing made easy: zest.releaser overview and installation

zest.releaser is collection of command-line programs to help you automate the task of releasing a Python project.

It does away with all the boring bits. This is what zest.releaser automates for you:

  • It updates the version number. The version number can either be in or version.txt (or in a __versions__ attribute in a Python file). For example, it switches you from 0.3.dev0 (current development version) to 0.3 (release) to 0.4.dev0 (new development version).
  • It updates the history/changes file. It logs the release date on release and adds a new heading for the upcoming changes (new development version).
  • It tags the release. It creates a tag in your version control system named after the released version number.
  • It optionally uploads a source release to PyPI. It will only do this if the package is already registered there (else it will ask, defaulting to ‘no’); zest releaser is careful not to publish your private projects!

Most important URLs

First the three most important links:

And… we’re automatically being tested by Travis and Landscape:

Compatibility / Dependencies

zest.releaser works on Python 2.7. Python 2.6 is not officially supported anymore since version 4.0: it may still work, but we are no longer testing against it. Python 3.3+ is supported.

To be sure: the packages that you release with zest.releaser may very well work on other Python versions: that totally depends on your package.

We depend on:

  • setuptools for the entrypoint hooks that we offer.
  • colorama for colorized output (some errors printed in red).
  • six for python2/python3 compatibility.

Since version 4.0 there is a recommended extra that you can get by installing zest.releaser[recommended] instead of zest.releaser. It contains a few trusted add-ons that we feel are useful for the great majority of zest.releaser users:

  • wheel for creating a Python wheel that we upload to PyPI next to the standard source distribution. Wheels are the new Python package format. Create or edit setup.cfg in your project (or globally in your ~/.pypirc) and create a section [zest.releaser] with create-wheel = yes to create a wheel to upload to PyPI. See for deciding whether this is a good idea for your package. Briefly, if it is a pure Python 2 or pure Python 3 package: just do it.
  • check-manifest checks your file for completeness, or tells you that you need such a file. It basically checks if all version controlled files are ending up the the distribution that we will upload. This may avoid ‘brown bag’ releases that are missing files.
  • pyroma checks if the package follows best practices of Python packaging. Mostly it performs checks on the file, like checking for Python version classifiers.
  • chardet, the universal character encoding detector. To do the right thing in case your readme or changelog is in a non-utf-8 character set.
  • readme to check your long description in the same way as pypi does. No more unformatted restructured text on your pypi page just because there was a small error somewhere. Handy.
  • twine for secure uploading via https to pypi. Plain setuptools doesn’t support this.


Just a simple pip install zest.releaser or easy_install zest.releaser is enough. If you want the recommended extra utilities, do a pip install zest.releaser[recommended].

Alternatively, buildout users can install zest.releaser as part of a specific project’s buildout, by having a buildout configuration such as:

parts =

recipe = zc.recipe.egg
eggs = zest.releaser[recommended]

Version control systems: svn, hg, git, bzr

Of course you must have a version control system installed. zest.releaser currently supports:

  • Subversion (svn).
  • Mercurial (hg).
  • Git (git).
  • Git-svn.
  • Bazaar (bzr).

Others could be added if there are volunteers! Git and mercurial support have been contributed years ago when we were working with bzr and subversion, for instance.

Available commands

Zest.releaser gives you four commands to help in releasing python packages. They must be run in a version controlled checkout. The commands are:

  • prerelease: asks you for a version number (defaults to the current version minus a ‘dev’ or so), updates the or version.txt and the CHANGES/HISTORY/CHANGELOG file (with either .rst/.txt/.markdown or no extension) with this new version number and offers to commit those changes to subversion (or bzr or hg or git)
  • release: copies the the trunk or branch of the current checkout and creates a version control tag of it. Makes a checkout of the tag in a temporary directory. Offers to register and upload a source dist of this package to PyPI (Python Package Index). Note: if the package has not been registered yet, it will not do that for you. You must register the package manually (python register) so this remains a conscious decision. The main reason is that you want to avoid having to say: “Oops, I uploaded our client code to the internet; and this is the initial version with the plaintext root passwords.”
  • postrelease: asks you for a version number (gives a sane default), adds a development marker to it, updates the or version.txt and the CHANGES/HISTORY/CHANGELOG file with this and offers to commit those changes to version control. Note that with git and hg, you’d also be asked to push your changes (since 3.27). Otherwise the release and tag only live in your local hg/git repository and not on the server.
  • fullrelease: all of the above in order.

There are two additional tools:

  • longtest: small tool that renders a’s long description and opens it in a web browser. This assumes an installed docutils (as it needs
  • lasttagdiff: small tool that shows the diff of the currently committed trunk with the last released tag. Handy for checking whether all the changes are adequately described in the changes file.


  • Reinout van Rees (Nelen & Schuurmans) is the originator and main author.
  • Maurits van Rees (Zest Software) added a heapload of improvements.
  • Kevin Teague (Canada’s Michael Smith Genome Sciences Center) added support for multiple version control systems, most notable Mercurial.
  • Wouter vanden Hove (University of Gent) added support for uploading to multiple servers, using collective.dist.
  • Godefroid Chapelle (BubbleNet) added /tag besides /tags for subversion.
  • Richard Mitchell (Isotoma) added Python 3 support.

Changelog for zest.releaser

6.4 (2015-11-13)

  • Fixed error when retrying twine command. Fixes #148 [maurits]

6.3 (2015-11-11)

  • Fixed exception when logging an exception when a twine command fails. [maurits]

6.2 (2015-10-29)


  • Use twine as library instead of as command. You no longer need to have twine on your PATH. Fixes issue #142. [maurits]

6.1 (2015-10-29)


  • Fixed registering on servers other than PyPI. We forgot to specify the server in that case. [maurits]

6.0 (2015-10-27)

  • Made twine a core dependency. We now always use it for registering and uploading. We require at least version 1.6.0, as this introduces the register command. [maurits]
  • When uploading with twine first use the twine register command. On PyPI, when the project is already registered, we do not call it again, but we can only check this for PyPI, not for other servers. Issue #128. [maurits]
  • Always exit with error code 1 when we exit explicitly. In some cases we would exit with success code 0 when we exited based on the answer to a question. This happened when the user did not want us to create the missing tags directory in subversion, and also after asking if the user wanted to continue even though ‘nothing changed yet’ was in the history. [maurits]
  • Extensions can now tell zest.releaser to look for specific required words in the history. Just add required_changelog_text to the prerelease data. It can be a string or a list, for example ["New:", "Fixes:"]. For a list, only one of them needs to be present. [maurits]
  • Look for the ‘Nothing changed yet’ text in the complete text of the history entries of the current release, instead of looking at it line by line. This means that zest releaser extensions can overwrite nothing_changed_yet in the prerelease data to span multiple lines. [maurits]
  • zest.releaser extensions can now look at history_insert_line_here in the prerelease data. On this line number in the history file they can add an extra changelog entry if wanted. [maurits]
  • Added history_last_release to the prerelease data. This is the text with all history entries of the current release. [maurits]
  • When using the --no-input option, show the question and the chosen answer. Otherwise in case of a problem it is not clear why the command stopped. Fixes issue #136. [maurits]

5.7 (2015-10-14)

  • The history/changelog file is now written back with the originally detected encoding. The functionality was added in 5.2, but only used for writing the, not the changelog. This is fixed now. [reinout]

5.6 (2015-09-23)

  • Add support for PyPy. [jamadden]

5.5 (2015-09-05)

  • The bin/longtest command adds the correct utf-8 character encoding hint to the resulting html so that non-ascii long descriptions are properly rendered in all browsers. [reinout]

5.4 (2015-08-28)

  • Requiring at least version 0.6 of the (optional, btw) readme package. The API of readme changed slightly. Only needed when you want to check your package’s long description with bin/longtest. [reinout]

5.3 (2015-08-21)

  • Fixed typo in svn command to show the changelog since the last tag. [awello]

5.2 (2015-07-27)

  • When we find no version control in the current directory, look a few directories up. When looking for version and history files, we look in the current directory and its sub directories, and not in the repository root. After making a tag checkout, we change directory to the same relative path that we were in before. You can use this when you want to release a Python package that is in a sub directory of the repository. When we detect this, we first offer to change to the root directory of the repository. [maurits]
  • Write file with the same encoding that we used for reading them. Issue #109. [maurits]

5.1 (2015-06-11)

  • Fix writing history/changelog file with non-ascii. Issue #109. [maurits]
  • Release zest.releaser as universal wheel, so one wheel for Python 2 and 3. As usual, we release it also as a source distribution. [maurits]
  • Regard “Skipping installation of (namespace package)” as warning, printing it in magenta. This can happen when creating a wheel. Issue #108. [maurits]

5.0 (2015-06-05)

  • Python 3 support. [mitchellrj]
  • Use the same readme library that PyPI uses to parse long descriptions when we test and render them. [mitchellrj]

4.0 (2015-05-21)

  • Try not to treat warnings as errors. [maurits]
  • Allow retrying some commands when there is an error. Currently only for commands that talk to PyPI or another package index. We ask the user if she wants to retry: Yes, no, quit. [maurits]
  • Added support for twine. If the twine command is available, it is used for uploading to PyPI. It is installed automatically if you use the zest.releaser[recommended] extra. Note that if the twine command is not available, you may need to change your system PATH or need to install twine explicitly. This seems more needed when using zc.buildout than when using pip. Added releaser.before_upload entry point. Issue #59. [maurits]
  • Added check-manifest and pyroma to the recommended extra. Issue #49. [maurits]
  • Python 2.6 not officially supported anymore. It may still work, but we are no longer testing against it. [maurits]
  • Do not accept y or n as answer for a new version. [maurits]
  • Use colorama to output errors in red. Issue #86 [maurits]
  • Show errors when uploading to PyPI. They were unintentionally swallowed before, so you did not notice when an upload failed. Issue #84. [maurits]
  • Warn when between the last postrelease and a new prerelease no changelog entry has been added. ‘- Nothing changed yet’ would still be in there. Issue #26. [maurits]
  • Remove code for support of collective.sdist. That package was a backport from distutils for Python 2.5 and earlier, which we do not support. [maurits]
  • Add optional support for uploading Python wheels. Use the new zest.releaser[recommended] extra, or run pip install wheel yourself next to zest.releaser. Create or edit setup.cfg in your project (or globally in your ~/.pypirc) and create a section [zest.releaser] with create-wheel = yes to create a wheel to upload to PyPI. See for deciding whether this is a good idea for your package. Briefly, if it is a pure Python 2 or pure Python 3 package: just do it. Issue #55 [maurits]
  • Optionally add extra text to commit messages. This can be used to avoid running Travis Continuous Integration builds. See To activate this, add extra-message = [ci skip] to a [zest.releaser] section in the setup.cfg of your package, or your global ~/.pypirc. Or add your favorite geeky quotes there. [maurits]
  • Fix a random test failure on Travis CI, by resetting AUTO_RESPONSE. [maurits]
  • Added clarification to logging: making an sdist/wheel now says that it is being created in a temp folder. Fixes #61. [reinout]
File Type Py Version Uploaded on Size
zest.releaser-6.4-py2.py3-none-any.whl (md5) Python Wheel py2.py3 2015-11-13 95KB
zest.releaser-6.4.tar.gz (md5) Source 2015-11-13 101KB
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