PEP: 101 Title: Doing Python Releases 101 Version: $Revision$ Last-Modified: $Date$ Author: barry@zope.com (Barry A. Warsaw), guido@python.org (Guido van Rossum) Status: Active Type: Informational Created: 22-Aug-2001 Post-History: Abstract Making a Python release is an arduous processes that takes a minimum of half a day's work even for an experienced releaser. Until recently, most -- if not all -- of that burden was borne by Guido himself. But several recent releases have been performed by other folks, so 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 name of that expert is given. Otherwise, assume the step is done by the Release Manager (RM), the designated person performing the release. Almost every place the RM is mentioned below, this step can also be done by the BDFL of course! XXX: We should include a dependency graph to illustrate the steps that can be taken in parallel, or those that depend on other steps. We use the following conventions in the examples below. Where a release number is given, it is of the form X.YaZ, e.g. 2.1a3 for Python 2.1 alpha 3, where "a" == alpha, "b" == beta, "rc" == release candidate. Final releases are named "releaseXY" so the branch tag is "releaseXY-branch" and the fork tag on the trunk is "releaseXY-fork". If a micro release number is used, then we'll say X.Y.MaZ. ___ At noon the day before the release, create a branch for X.YaZ. All Python development happens on the trunk. Making releases from a branch allows development by the community to continue without impacting what ends up in the release. There's a natural tension here though: branching too soon causes headaches when the branch has to be merged back into the trunk, while branching too late can cause dependency problems with documentation and Windows release steps. The compromise is to create the branch at noon, local time, the day before the release. This should give enough time to Fred to make the documentation, then for Tim to create the Windows installer, both of which need to happen before the release can be announced. It's also short enough that hopefully not too many trunk changes will need to be merged into the branch, or vice versa. Once the branch is made, only the RM or his appointed bots are allowed to make commits to the branch. You can assume that Fred is a bot for the Doc/ tree, Tim is a bot for the Windows stuff, and Jack is a bot for Mac stuff. Anyone can continue to make checkins on the trunk, but if such a change should be merged into the branch, the committer must indicate this in the checkin message. It is the responsibility of the RM to decide on a case-by-case basis which trunk modifications should be merged into the branch. To create a branch the following steps are taken: ___ Do a CVS update with the -A, -d, and -P flags, e.g. % cvs -q update -d -P -A ___ CVS tag the trunk with the symbolic name "rXYaZ-fork", e.g. % cvs tag r22a3-fork ___ Make the branch with the symbolic name "rXYaZ-branch", e.g. % cvs tag -b r22a3-branch ___ Check out a clean version of the branch 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. % cvs -d -q co -d python-22a3 -r r22a3-branch python/dist/src ___ Send an email to python-dev@python.org indicating the fork and branch tags you've just created. ___ Put a freeze on check ins into the branch. At this point, nobody except the RM should make any commits to the branch (or his duly assigned agents, i.e. Guido the BDFL, Fred Drake for documentation, or Tim Peters for Windows). If the RM screwed up and some desperate last minute change to the branch is necessary, it can mean extra work for Fred and Tim. So try to avoid this! ___ In the branch, change Include/patchlevel.h in two places, to reflect the new version number you've just created. You'll want to change the PY_VERSION macro, and one or several of the version subpart macros just above PY_VERSION, as appropriate. ___ For the next few hours, selectively merge stuff from trunk into branch. For each change you see on the trunk (i.e. via the python-checkins mailing list), you need to decide whether the change should also be applied to the branch. There is a tension here. Announcing the branch often jogs people's natural tendency to procrastinate so some very useful patches end up getting checked in at the last moment. But the Windows and Docs releases tend to be built many hours before the source release, and changes to the branch can force a lot of wasted effort to rebuild them. The best advice is to be judicious and to consult Fred and Tim before adding anything big. You really want to avoid skew between the various platform releases. Note that committers of changes to the trunk SHOULD include in the checkin message, a note indicating the suitability of their patch for the branch. If so, it's fairly easy to apply the change by diff'ing the file and patching it manually. You can also sometimes get away with just copying the file from the trunk directory to the branch directory, but be careful so you don't lose changes that only exist in the branch! ___ After creating the branch, the most important thing to do next is to update the Misc/NEWS file. Tim will need this in order to do the Windows release and he likes to stay up late. This step can be pretty tedious, so it's best to get to it immediately after making the branch, or even before you've made the branch. The sooner the better (but again, watch for new checkins up until the release is made!) Add high level items new to this release. E.g. if we're releasing 2.2a3, there must be a section at the top of the file explaining "What's new in Python 2.2a3". It will be followed by a section entitled "What's new in Python 2.2a2". Note that you /hope/ that as developers add new features to the trunk, they've updated the NEWS file accordingly. You can't be positive, so double check. If you're a Unix weenie, it helps to verify with Tim Peters about changes on Windows, and Jack Jansen about changes on the Mac. This command should help you: % cvs log -rr22a1: | python Tools/scripts/logmerge.py > /tmp/news.txt IOW, you're printing out all the cvs log entries from the previous release until now. You can then troll through the news.txt file looking for interesting things to add to NEWS. ___ Check your NEWS changes into the branch and into the trunk. ___ Once the branch is frozen, Fred Drake needs to create the HTML from the documentation. He does this and uploads the file to www.python.org. Then he tells Tim Peters where this file is. This may generate some last minute changes on the branch. Once Fred is done, there can be no further checkins on the branch in the Doc/ directory -- not even by the RM. For final releases, Fred also sends email to Milan Zamazal for conversion to the GNU Info format, and to Hernan M. Foffani for conversion to HTML Help. Note that Fred is responsible both for merging doc changes from the trunk to the branch AND for merging any branch changes from the branch to the trunk during the cleaning up phase. Basically, if it's in Doc/, Fred will take care of it. ___ Tim Peters grabs the HTML and uses this to build the Windows installer. Tim then creates a new "release" named X.YaZ on the SourceForge file release manager. (Although, if you get there first, you should create the new release.) (Diversion: SF's file manager has "packages" and "releases". We use packages to name major upcoming releases, e.g. python-2.2 or python-2.1.1. Inside each package are a number of "releases" for each new actual release -- i.e. the thing you're building. An example of a release name is 2.2a3. Once created, packages and releases are never deleted, but old ones are hidden to reduce confusion. More on this below.) If this is the first release for this major Python version, Tim will create a new package containing the major Python version number. ___ Tim performs his Windows magic, generating an installer executable. He uploads this file to SourceForge under the release he just created. He then sends the RM a notice which includes the MD5 checksum of the Windows executable. Note that Tim's creation of the Windows executable may generate a few more commits on the branch. Tim will be responsible for merging Windows-specific changes from trunk to branch, and from branch to trunk. ___ It's Noon! Now, you're ready to build the source tarball. First cd to your working directory for the branch. E.g. % cd .../python-22a3 ___ Do a "cvs update" in this directory. Do NOT include the -A flag! You should not see any "M" files, but you may see several "P" files. I.e. you better not have any uncommitted changes in your working directory, but you may pick up some of Fred's or Tim's last minute changes. ___ Now tag the branch using a symbolic name like "rXYaZ", e.g. r22a3 % cvs tag r22a3 ___ Change to a neutral directory, i.e. one in which you can do a fresh, virgin, cvs export of the branch. You will be creating a new directory at this location, to be named "Python-X.YaZ". Do a CVS export of the tagged branch. % cd ~ % cvs -d export -rr22a3 -d Python-2.2a3 python/dist/src ___ Generate the tarball. Note that we're not using the `z' option on the tar command because 1) that's only supported by GNU tar as far as we know, and 2) we're going to max out the compression level, which isn't a supported option. % tar cf - Python-2.2a2 | gzip -9 > Python-2.2a2.tgz ___ Calculate the MD5 checksum of the tgz file you just created % md5sum Python-2.2a2.tgz Note that if you don't have the md5sum program, there is a Python replacement in the Tools/scripts/md5sum.py file. ___ 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-2.2a3.tgz % cd Python-2.2a3 % ls (Do things look reasonable?) % ./configure (Loads of configure output) % make test (Do all the expected tests pass?) 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. ___ Start your upload to SF. You need to get Python-2.2a3.tgz into SourceForge. This can take a while both because of the time it takes to upload such a huge file, /and/ because SF has a 30 minute delay built into the file release process. The next few steps can be taken in parallel, so it's best to start the upload now and keep an eye on its progress. I've found that the `ncftpput' program is a great tool to use if you have it available. You can execute the following command to do the upload: % ncftpput upload.sf.net incoming Python-2.2a3.tgz If you don't have ncftpput around, you can use whatever ftp client you're comfortable with. Just be sure that you're uploading this to the "incoming" directory on upload.sf.net. ___ You also need to upload the tgz file to creosote.python.org. Usually Tim will have already uploaded the exe file to creosote, but if not, you'll need to do that too. These steps can take a long time depending on your network bandwidth. You have two choices: 1) Upload them to SF first, then wget them from creosote. Pros: easy to do; much friendlier to your own personal bandwidth. Cons: can take even longer because you're subject to the 30 minute SF file upload delay, and the upload rate from SF->creosote never seems to get above 20 KB/sec. 2) scp both files from your own machine to creosote. Pros: you avoid the 30 minute SF delay. Cons: you don't get much else done if you're on a small pipe. I usually opt for #2. ___ While you're waiting, you can start twiddling the web pages to include the announcement. ___ In the python.org web site CVS tree, cd to the X.Y subdirectory, and copy index.ht to new-index.ht. Be sure to do a "cvs update" first! % cd .../pydotorg % cvs -q up -P -d % cd 2.2 % cp index.ht new-index.ht ___ Edit the file for content: usually you can globally replace X.Ya(Z-1) with X.YaZ. However, you'll need to think about the "What's New?" section. You also need to watch out about two specific links in the file, one which references "the full scoop" on changes -- a shownotes link, and one which references the downloads on SF -- a showfiles link. You won't be able to update either link until you've completed the steps below. For now just note what needs to change. ___ Also, update the MD5 checksums. ___ Preview the web page by doing a "make" -- NOT a "make install". View the page via a file: url. ___ Similarly, edit the ../index.ht file, i.e. the python.org home page. In the Big Blue Announcement Block, move the paragraph for the new version up to the top and boldify the phrase "Python X.YaZ is out". Edit for content, and preview as above. Do NOT do a "make install" yet! ___ Now we're waiting for the ncftpput command, and the scp to creosote to finish. Da de da, da de dum, hmm, hmm, dum de dum. ___ Do the SourceForge file release dance. ___ Go to the Python project and click on "Admin" ___ Click on "Edit/Release Files" ___ Since Tim has usually by now created the package and release we're going to use, scroll down and click on "Edit Releases" for the package we're releasing into. ___ Find the release named X.YaZ and click on "Edit This Release" You should now perform Step 1 of the file release dance... ___ The "Status" field should be "Active" not "Hidden" ___ In the text box that says "Paste The Notes In", paste in all the "What's New" entries from the Misc/NEWS file that describe this major version of Python, /not/ just the ones for this particular release. E.g. If we're releasing Python 2.2a3, we'd include the "What's New" sections for Python 2.2a3, 2.2a2, and 2.2a1. ___ Leave the "Paste The Change Log In" section blank, but click on "Preserve my pre-formatted text". ___ Hit the Submit/Refresh button for Step 1. This will bring you back to the file release page. DO NOT do the following step until your ftp upload is complete! Once it is, you can perform Step 2 of the file release dance... ___ Click on the checkbox next to the file Python-X.YaZ.tgz. Be sure no other box is checked! Then click on the "Add Files and/or Refresh View" button for Step 2. And now, Step 3... ___ There should be exactly two files listed here, one is the tgz file you just added, and the other is the exe file that Tim added earlier. ___ For the tgz file, be sure that the "Processor" field says "Any" and the "File Type" field says "Source .gz". ___ Click on "Update/Refresh" for the .tgz file. ___ For the exe file, make sure that the "Processor" field says "i386" and the "File Type" field says "Other". Tim usually gets this right , but if not, make any necessary changes and click on "Update/Refresh" for the exe file. Step 4... DO NOT DO STEP 4 NOW. Wait until after you send out the email announcement to send the SF email notice. ___ Still on SF, click on the "Files" button at the top of the page. Find the release you've just made and click on it -- not on the tgz or exe file, but on the release link under the package name. E.g. package named python-2.2, click on the "2.2a3" link. This should be a page that says "Release Name: X.YaZ" and it should contain the "What's New" sections you pasted in earlier. Note the url of this page. Copy and paste it into the pydotorg/X.Y/new-index.ht file you created above. This is the "shownotes" link mentioned earlier. ___ Now click on the "Summary" link at the top of the page and scroll down to the "Latest File Releases" section. Find the package you just made a release for (the Version should be X.YaZ, and the Date should be today's date). Click on the "Download" link. Your new release should be highlighted in pink. Note the url for this page. Copy and paste it into the pydotorg/X.Y/new-index.ht file from above. This is the "showfiles" link mentioned earlier. ___ Now you need to go to creosote.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 "2.2" which contains Python-2.2a2.exe and Python-2.2a2.tgz, along with a "prev" subdirectory containing Python-2.2a1.exe and Python-2.2a1.tgz. So... ___ On creosote, cd to ~ftp/pub/python/X.Y 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. ___ Move the .tgz file and the .exe file to this directory. 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. ___ Update the X.Y/bugs.ht file if necessary. It is best to get BDFL input for this step. ___ Now preview the new-index.ht file once more. IMPORTANT: follow every link on the page to make sure it goes where you expect it to go, and that what you expect to be there is there. ___ If everything looks good, move new-index.ht to index.ht and do a "make install" in this directory. Go up to the parent directory (i.e. the root of the web page hierarchy) and do a "make install" there too. You're release is now 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 one of Guido's earlier announcements as a template, but please 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 ___ Go back to the file releases page on SF and complete Step 4, sending out the email notification. ___ Send a SourceForge News Item about the release. From the project's "menu bar", select the "News" link; once in News, select the "Submit" link. Type a suitable subject (e.g. "Python 2.2c1 released" :-) in the Subject box, add some text to the Details box (at the very least including the release URL at www.python.org and the fact that you're happy with the release) and click the SUBMIT button. Feel free to remove any old news items. Now it's time to do some cleanup. These steps are very important! ___ Go back to SF, Admin->Edit/Release Files. Click on "Edit Releases" for the package you just added to. For each old release, click on "Edit This Release" and under Step 1, change the "Status" to "Hidden". Click on the Step 1 Submit/Refresh button. ___ Merge the branch back 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. ___ 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: % cvs -d co -d python-clean python/dist/src ___ 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-22a2 | grep ^diff | grep -v CVS \ > /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 "cvs commit". Use as your log message something like "Merging the rXYaZ-branch tag back into the trunk". ___ Edit the file Include/patchlevel.h so that the PY_VERSION string says something like "X.YaZ+". Note the trailing `+' indicating that the trunk is going to be moving forward with development. E.g. the line should look like: #define PY_VERSION "2.2a2+" Make sure that the other PY_ version macros contain the correct values. Commit this change. ___ For the extra paranoid, do a completely clean test of the release. This includes downloading the tarball from either SourceForge or 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! Step 5 ... Verify! This can be interleaved with Step 4. Pretend you're a user: download the files from python.org *and* SourceForge, and make Pythons from them. 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. What Next? 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! Actually, there is one more step. You should turn over ownership of the branch to Jack Jansen. All this means is that now he will be responsible for making commits to the branch. He's going to use this to build the MacOS versions. He may send you information about the Mac release that should be merged into the informational pages on SourceForge or www.python.org. When he's done, he'll tag the branch something like "rX.YaZ-mac". He'll also be responsible for merging any Mac-related changes back into the trunk. Final Release Notes The Final release of any major release, e.g. Python 2.2 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. The Windows and source releases benefit from the close proximity of the respective release-bots. But the Mac-bot, Jack Jansen, is 6 hours away. So we add this extra step to the release process for a final release: ___ Hold up the final release until Jack approves, or until we lose patience . Windows Notes Windows has a GUI 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, Tim 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. 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 (Tim uses "random" ) 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 all of the above on at least one flavor of Win9x, and one of NT/2000. On NT/2000, try both an Admin and a plain User (not Power User) account. WRT Step 5 above (verify the release media), since by the time release files are ready to download Tim 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. Local Variables: mode: indented-text indent-tabs-mode: nil End: