PEP: 101
Title: Doing Python Releases 101
Version: $Revision: 66760 $
Last-Modified: $Date: 2008-10-02 14:57:20 -0700 (Thu, 02 Oct 2008) $
Author: Barry A. Warsaw <barry at python.org>, Guido van Rossum <guido at python.org>
Status: Active
Type: Informational
Created: 22-Aug-2001
Post-History: 

Abstract

    Making a Python release is a thrilling and crazy process.  You've heard
    the expression "herding cats"?  Imagine trying to also saddle those
    purring little creatures up, and ride them into town, with some of their
    buddies firmly attached to your bare back, anchored by newly sharpened
    claws.  At least they're cute, you remind yourself.

    Actually, no that's a slight exaggeration <wink>.  The Python release
    process has steadily improved over the years and now, with the help of our
    amazing community, is really not too difficult.  This PEP attempts to
    collect, in one place, all the steps needed to make a Python release.  It
    is organized as a recipe and you can actually print this out and check
    items off as you complete them.


How to Make A Release

    Here are the steps taken to make a Python release.  Some steps are
    more fuzzy than others because there's little that can be
    automated (e.g. writing the NEWS entries).  Where a step is
    usually performed by An Expert, the role of that expert is given.
    Otherwise, assume the step is done by the Release Manager (RM),
    the designated person performing the release.  The roles and their
    current experts are:

    * RM = Release Manager: Barry Warsaw <barry@python.org> (US/Eastern)
    * WE = Windows: Martin von Loewis <martin@v.loewis.de> (Central Europe)
    * ME = Mac: Ronald Oussoren <ronaldoussoren@mac.com> (Central Europe)
    * IE = Idle Expert: ??

    NOTE: It is highly recommended that the RM contact the Experts the day
          before the release.  Because the world is round and everyone lives
          in different timezones, the RM must ensure that the release tag is
          created in enough time for the Experts to cut binary releases.

          IT IS HIGHLY RECOMMENDED THAT YOU AT LEAST TAG THE TREE 24 HOURS
          BEFORE A FINAL RELEASE.  This will give the Experts enough time to
          do their bits before the announcement goes out.

    XXX: We should include a dependency graph to illustrate the steps
    that can be taken in parallel, or those that depend on other
    steps.

    As much as possible, the release steps are automated and guided by the
    release script, which is available in the Python sandbox.  The release
    script is currently being maintained here:

        http://svn.python.org/view/sandbox/trunk/release/

    We use the following conventions in the examples below.  Where a release
    number is given, it is of the form X.YaZ, e.g. 2.6a3 for Python 2.6 alpha
    3, where "a" == alpha, "b" == beta, "c" == release candidate.

    Final releases are named "releaseXY".  The branch tag is "releaseXY-maint"
    because this will point to the long lived maintenance branch.  The fork
    tag on the trunk is "releaseXY-fork".  If a micro release number is used,
    then we'll say X.Y.MaZ.

    This helps by performing several automatic editing steps, and guides you
    to perform some manual editing steps.

  ___ Log into irc.freenode.net and join the #python-dev channel.

      You probably need to coordinate with other people around the world.
      This IRC channel is where we've arranged to meet.

  ___ Impose a check-in freeze by sending email to python-committers@python.org

      At this point, nobody except the RM or his duly assigned agents should
      make any commits to the branches.  The assigned agents are either from
      the list above or by coordination as necessary.  If a checkin needs to
      be made, make sure to state in the checkin comment that the change was
      approved.  If the RM screwed up and some desperate last minute change to
      the branch is necessary, it can mean extra work for others.  So try to
      avoid this!

      The RM has full authority to revert any unapproved commits.

  ___ Check to see if there are any showstopper bugs.

      Go to http://bugs.python.org and look for any open bugs that can block
      this release.  You're looking at the Priority of the open bugs for the
      release you're making; here are the relevant definitions:

      release blocker - Stops the release dead in its tracks.  You may not
                        make any release with any open release blocker bugs.

      deferred blocker - Doesn't block this release, but it will block a
                         future release.  You many not make a final or
                         candidate release with any open deferred blocker
                         bugs.

      critical - Important bugs that should be fixed, but which does not block
                 a release.

      Review the release blockers and either resolve them, bump them down to
      deferred, or stop the release and ask for community assistance.  If
      you're making a final or candidate release, do the same with any open
      deferred.

  ___ Check the stable buildbots.

      Go to http://www.python.org/dev/buildbot/stable/

      (the trailing slash is required).  Look at the buildbots for the release
      you're making.  Ignore any that are offline (or inform the community so
      they can be restarted).  If what remains are (mostly) green buildbots,
      you're good to go.  If you have non-offline red buildbots, you may want
      to hold up the release until they are fixed.  Review the problems and
      use your judgement, taking into account whether you are making an alpha,
      beta, or final release.

  ___ Regenerate Lib/pydoc-topics.py

      cd to the Doc directory and type ``make pydoc-topics``.  Then copy
      ``build/pydoc-topics/pydoc-topics.py`` to ``Lib/pydoc-topics.py``.

  ___ Bump version numbers via the release script.

      .../sandbox/release/release.py --bump X.YaZ

      This automates updating various release numbers, but you will have to
      modify a few files manually.  If your $EDITOR environment variable is
      set up correctly, release.py will pop up editor windows with the files
      you need to edit.

      It is important to update the Misc/NEWS file, however in recent years,
      this has become easier as the community is responsible for most of the
      content of this file.  You should only need to review the text for
      sanity, and update the release date with today's date.

      If the minor (middle) digit of the version number changes, you will be
      prompted to update some additional files:

      ___ The LICENSE file.  Add the pending version to the list of releases,
          and be sure to check the release dates. 

      ___ There's a copy of the license in Doc/license.rst

      ___ Doc/tutorial/interpreter.rst (2 references to '[Pp]ython26', one
          to 'Python 2.6').

      ___ Doc/tutorial/stdlib.rst and Doc/tutorial/stdlib2.rst, which have
          each one reference to '[Pp]ython26'.

  ___ Check the years on the copyright notice.  If the last release
      was some time last year, add the current year to the copyright
      notice in several places:

      ___ README
      ___ LICENSE (make sure to change on trunk and the branch)
      ___ Python/getcopyright.c
      ___ Doc/README.txt (at the end)
      ___ Doc/copyright.rst
      ___ Doc/license.rst
      ___ PC/python_nt.rc sets up the DLL version resource for Windows
          (displayed when you right-click on the DLL and select
          Properties).
      ___ The license.ht file for the distribution on the website
          contains what purports to be an HTML-ized copy of the LICENSE
          file from the distribution.  BROKEN

  ___ For major releases (e.g. 2.6 final), move any historical "what's
      new" entries from Misc/NEWS to Misc/HISTORY.

  ___ Check with the IDLE maintainer to be sure that
      Lib/idlelib/NEWS.txt has been similarly updated.

  ___ For a final release, edit the first paragraph of
      Doc/whatsnew/X.Y.rst to include the actual release date; e.g. "Python
      2.5 was released on August 1, 2003."  There's no need to edit this for
      alpha or beta releases.  Note that Andrew Kuchling often takes care of
      this.

  ___ Tag the release for X.YaZ

      .../sandbox/release/release.py --tag X.YaZ

  ___ Send an email to the Experts so that they can build the binaries.

      For a final release, the RM may block at this point waiting for
      confirmation from the Experts.

  ___ If this is a final major release, branch the tree for X.YaZ

      When making a major release (e.g., for 2.6), you must create the
      long-lived maintenance branch.  To create a _branch_ (e.g.,
      release26-maint), do the following:

      .../sandbox/release/release.py --branch X.Y

      ___ If you just made the release branch, check out a clean version
          into a new directory.  You'll be doing a lot of work in this
          directory and you want to keep it straight from your trunk working
          directory.  E.g.

          % svn co \
            svn+ssh://pythondev@svn.python.org/python/branches/release26-maint

      ___ cd release26-maint  # cd into the branch directory.

  ___ XXX The WE builds the Windows helpfile, using (in Doc/) either

        $ make htmlhelp   (on Unix)

      or

        > make.bat htmlhelp   (on Windows)

      to create suitable input for HTML Help Workshop in
      build/htmlhelp. HTML Help Workshop is then fired up on the
      created python26.hhp file, finally resulting in an
      python26.chm file.  He then copies the file into the Doc
      directories of the build trees (once for each target architecture).

      XXX The CHM file should also be scp'd to the docs download location.

  ___ XXX The WE then generates Windows installer files for each Windows
      target architecture (for Python 2.6, this means x86
      and AMD64). He has one checkout tree per target architecture,
      and builds the pcbuild.sln project for the appropriate
      architecture. He then edits Tools/msi/config.py to update
      full_current_version, sets snapshot to False and runs msi.py with 
      ActivePython 2.5 or Python 2.5 with pywin32.
      For that to work, the following prerequisites must be met:

      - PC\icons.mak must have been run with nmake.

      - The cmd.exe window in which this is run must have Cygwin/bin
        in its path (atleast for x86).

      - The cmd.exe window must have MS compiler tools for the target
        architecture in its path (VS 2003 for x86, the platform
        SDK for AMD64).

      - The cmd.exe window must also have cabarc.exe from the CAB SDK
        in its path.

      The WE checksums the files (*.msi and *.chm), uploads them to
      some place in the net, and emails you the location and md5sums.

  ___ Time to build the source tarball.  If you created a branch, be
      sure to cd to your working directory for the branch.  E.g.

      % cd .../python26

  ___ Do a "svn update ; svn status" in this directory.

      You should not see any files.  I.e. you better not have any uncommitted
      changes in your working directory, but you may pick up some of the
      expert's last minute changes.

  ___ If you've seen updates to existing files, update the branches.

      ___ Delete the old tag branch and re-tag the tree
      ___ Delete the maintenance branch and re-branch the trunk.

      This should be rare and indicates a breakdown in the process.

  ___ Use the release script to create the gzip and bz2 tarballs, md5
      checksums, and gpg signature files.

      .../sandbox/release/release.py --export X.YaZ

      This will leave all the relevant files in a subdirectory called 'dist'.

  ___ scp the files to your home directory on dinsdale.python.org.

      While you're waiting for the files to finish uploading, you can continue
      on with the remaining tasks.  You can also ask folks on #python-dev to
      download the files as they finish uploading so that they can test them
      on their platforms as well.

  ___ Now you want to perform the very important step of checking the
      tarball you just created, to make sure a completely clean,
      virgin build passes the regression test.  Here are the best
      steps to take:

      % cd /tmp
      % tar zxvf ~/Python-2.6c2.tgz  # tar xjvf ~/Python-2.6c2.tar.bz2
      % cd Python-2.6c2
      % ls
      (Do things look reasonable?)
      % ls Lib
      (Are there stray .pyc files?)
      % ls Doc/tools
      (Make sure it doesn't contain "docutils", "sphinx", "jinja" or
      "pygments" directories.)
      % ./configure
      (Loads of configure output)
      % make test
      (Do all the expected tests pass?)

      If you're feeling lucky and have some time to kill, or if you are making
      a release candidate or final release, run the full test suite:

      % make TESTOPTS='-u all' test

      If the tests pass, then you can feel good that the tarball is
      fine.  If some of the tests fail, or anything else about the
      freshly unpacked directory looks weird, you better stop now and
      figure out what the problem is.

  ___ For the extra paranoid, do a completely clean test of the
      release.  This includes downloading the tarball from
      www.python.org.

  ___ Make sure the md5 checksums match.  Then unpack the tarball,
      and do a clean make test.

      % make distclean
      % ./configure
      % make test

      To ensure that the regression test suite passes.  If not, you
      screwed up somewhere!

  ___ Now you need to go to dinsdale.python.org and move all the files
      in place over there.  Our policy is that every Python version gets its
      own directory, but each directory may contain several releases.  We keep
      all old releases, moving them into a "prev" subdirectory when we have a
      new release.

      So, there's a directory called "2.6" which contains Python-2.6a2.exe and
      Python-2.6a2.tgz, along with a "prev" subdirectory containing
      Python-2.6a1.msi, Python-2.6a1.tgz, Python-2.6a1.tar.bz2, etc.

      ___ On dinsdale, cd /data/ftp.python.org/pub/python/X.Y[.Z]
          creating it if necessary.

      ___ Move the previous release files to a directory called 'prev'
          creating the directory if necessary (make sure the directory has
          g+ws bits on).  If this is the first alpha release of a new Python
          version, skip this step.

          For pre-releases (alpha, beta, rc), don't move things into a 'prev'
          directory, You'll move everything in there when the final release
          comes out.

      ___ Move the release .tgz, tar.bz2, and .msi files into place

          Make sure they are world readable.  They should also be group
          writable, and group-owned by webmaster.

      ___ md5sum the files and make sure they got uploaded intact.

      ___ If this is a final release: Move the built docs to
          /data/ftp.python.org/pub/python/doc/X.Y[.Z], and adapt the
          "current" symlink in that directory.

  Now it's time to twiddle the web site.

  To do these steps, you must have the permission to edit the website.  If you
  don't have that, ask someone on pydotorg@python.org for the proper
  permissions.  It's insane for you not to have it.

  I'm not going to go into the details of building the site or pushing it
  live.  Plenty of people on pydotorg can help you, and there's a good README
  once you get the branch.  All the directories below are named relative to
  the data subdirectory unless otherwise noted.

  This page will probably come in handy:

  http://docutils.sourceforge.net/docs/user/rst/quickref.html

  None of the web site updates are automated by release.py.

  ___ Build the basic site.

      In the top directory, do an `svn update` to get the latest code.  In the
      build subdirectory, do `make` to build the site.  Do `make serve` to
      start service the pages on localhost:8005.  Hit that url to see the site
      as it is right now.  At any time you can re-run `make` to update the
      local site.  You don't have to restart the server.

      Don't `svn commit` until you're all done!

  ___ If this is the first release for this version (even a new patch
      version), you'll need to create a subdirectory inside download/releases
      to hold the new version files.  It's probably a good idea to copy an
      existing recent directory and twiddle the files in there for the new
      version number.

  ___ Add a news section item to the front page by editing newsindex.yml.  The
      format should be pretty self evident.

  ___ If this is a final release...

      ___ update the 'Quick Links' section on the front page.  Edit the
          top-level `content.ht` file.

      ___ update the download page, editing `download/content.ht`

      ___ edit the previous release's last release content.ht page to point to
          the new release.

      ___ Mention the release as the most recent stable one in
          `doc/faq/general.ht` (section "How stable is Python?")

      ___ update `doc/content.ht` to indicate the new current documentation
          version, and remove the current version from any 'in development'
          section. Update the version in the "What's New" link.

      ___ Add the new version to `doc/version/content.ht`.

  ___ Edit download/releases/content.ht to update the version numbers for
      this release.  There are a bunch of places you need to touch:

      ___ The subdirectory name as the first element in the Nav rows.
      ___ Possibly the Releases section, and possibly in the experimental
          releases section if this is an alpha, beta or release candidate.

  ___ Update the version specific pages.

      ___ cd to download/releases/X.Y.Z
      ___ Edit the version numbers in content.ht
      ___ Copy the new .asc files into place
      ___ Update the md5 checksums

      ___ Copy Misc/NEWS to download/releases/X.Y.Z/NEWS.txt
      ___ Copy Lib/idlelib/NEWS.txt to download/releases/X.Y.Z/IDLENEWS.txt

      Note, you don't have to copy the actual .tgz or tar.bz2 tarballs into
      this directory because they only live on dinsdale in the ftp directory.

  ___ When everything looks good, `svn commit` in the data directory.  This
      will trigger the live site to update itself, and at that point the
      release is live.

  Now it's time to write the announcement for the mailing lists.  This is the
  fuzzy bit because not much can be automated.  You can use an earlier
  announcement as a template, but edit it for content!

  ___ Once the announcement is ready, send it to the following
      addresses:

      python-list@python.org
      python-announce@python.org
      python-dev@python.org

  Now it's time to do some cleaning up.  These steps are very important!

  ___ If you made a non-maintenance branch, be sure to merge it into
      the trunk!  Now that we've released this branch, we don't need it any
      more.  We've already tagged it so we can always reproduce it.  Note that
      merging branches is a bit of a black art, but here's what's worked for
      us.

      NOTE: If this was an X.Y major release, we will be using this as
      the maintenance branch for a long time to come.

      ___ Check out a completely clean, virgin working directory of the
          trunk, by doing this in the directory that is the parent of
          your branch working directory python-XYaZ:
          % svn co \
              svn+ssh://pythondev@svn.python.org/python/trunk python-clean

      ___ Run a diff against your branch by doing this in the common
          parent directory containing both python-clean and python-XYaZ:
          % diff -r python-clean python-26a2 | grep ^diff | grep -v /.svn/ \
              > /tmp/diffcmd.sh

      ___ Edit diffcmd.sh to get rid of files that you know don't have
          important changes.  You're looking for files that have updates
          in the branch that haven't made it to the trunk.

          Generally you can ignore any changes to the Doc or Mac
          subdirectories, or any changes to Windows related files.  The
          sub-RMs for those parts will take care of any necessary merges
          from the branch to the trunk.

          If you've been diligent about merging changes from the trunk
          into the branch, there shouldn't be many of these files.

      ___ Edit /tmp/diffcmd.sh, changing all the -r's into -u's.  Run
          the /tmp/diffcmd.sh command like so:
          % sh /tmp/diffcmd.sh > /tmp/pydiff.txt

      ___ Attempt to patch your python-clean working directory.  Do this
          first, noting that --dry-run does not actually apply any
          patches, it just makes sure that the patch command runs
          successfully to completion:
          % patch -p1 --dry-run < /tmp/pydiff.txt

      ___ If this goes well, run it again, taking out the --dry-run
          option.  If this fails, or if it prompts you for a file to
          patch, try using -p0 instead of -p1.  Otherwise, your diff
          command was messed up, so try again.

      ___ cd to python-clean and do a "svn commit".  Use as your log
          message something like "Merging the rXYaZ-maint tag back into
          the trunk".

  ___ Do the guided post-release steps with the release script.

      .../sandbox/release/release.py --done X.YaZ

      Review and commit these changes.

  ___ Send email to python-committers informing them that the branch has been
      unfrozen.

  ___ Update the release PEP (e.g. 361) with the release dates.

  ___ In the tracker at http://bugs.python.org, flip all the deferred blocker
      issues back to release blocker for the next release.


What Next?

  __ Verify!  Pretend you're a user: download the files from python.org, and
     make Python from it. This step is too easy to overlook, and on several
     occasions we've had useless release files.  Once a general server problem
     caused mysterious corruption of all files; once the source tarball got
     built incorrectly; more than once the file upload process on SF truncated
     files; and so on.

  __ Rejoice.  Drink.  Be Merry.  Write a PEP like this one.  Or be
     like unto Guido and take A Vacation.

  You've just made a Python release!


Final Release Notes

    The Final release of any major release, e.g. Python 2.5 final, has
    special requirements, specifically because it will be one of the
    longest lived releases (i.e. betas don't last more than a couple
    of weeks, but final releases can last for years!).

    For this reason we want to have a higher coordination between the
    three major releases: Windows, Mac, and source.  So we add this
    extra step to the release process for a final release:

    ___ Hold up the final release until the Experts approve, or until we
        lose patience <wink>.


Windows Notes

    Windows has a MSI installer, various flavors of Windows have
    "special limitations", and the Windows installer also packs
    precompiled "foreign" binaries (Tcl/Tk, expat, etc).  So Windows
    testing is tiresome but very necessary.

    Concurrent with uploading the installer, the WE installs Python
    from it twice: once into the default directory suggested by the
    installer, and later into a directory with embedded spaces in its
    name.  For each installation, he runs the full regression suite
    from a DOS box, and both with and without -0. For maintenance
    release, he also tests whether upgrade installations succeed.

    He also tries *every* shortcut created under Start -> Menu -> the
    Python group.  When trying IDLE this way, you need to verify that
    Help -> Python Documentation works.  When trying pydoc this way
    (the "Module Docs" Start menu entry), make sure the "Start
    Browser" button works, and make sure you can search for a random
    module (like "random" <wink>) and then that the "go to selected"
    button works.

    It's amazing how much can go wrong here -- and even more amazing
    how often last-second checkins break one of these things.  If
    you're "the Windows geek", keep in mind that you're likely the
    only person routinely testing on Windows, and that Windows is
    simply a mess.

    Repeat the testing for each target architecture.  On XP/2003, try
    both an Admin and a plain User (not Power User) account. If you
    can, also test the installer on Windows 9x.

    WRT Step 5 above (verify the release media), since by the time
    release files are ready to download the WE has generally run many
    Windows tests on the installer he uploaded, he usually doesn't do
    anything for Step 5 except a full byte-comparison ("fc /b" if
    using a Windows shell) of the downloaded file against the file he
    uploaded.


Copyright

    This document has been placed in the public domain.