• Table of contents
• Make a new release
  • When to make a new release
  • Versioning considerations for libraries
  • osmocom-release.mk
    • Dependencies
    • TODO-RELEASE file format and maintenance
  • How to make a new release
    • Extra steps for Libraries
    • Release steps
  • Which new release to make
  • Deprecation policy
  • How to (re)tag a new release
  • GPG: Have a matching user id
  • GPG: failed to sign
• Creating a patch release
• Dependency graph

Make a new release¶

The efforts to automate the release process are tracked in https://projects.osmocom.org/issues/1861

When to make a new release¶

Various Osmocom projects depend on others.

Proposed policy:

• master branch is expected to depend on latest master branches of depended-upon projects
• make release of depended-upon projects if necessary before making non-library project release
• make sure that we have correct version dependencies before making non-library project release

Alternatively/additionally we can make timely releases of non-library projects (and corresponding depended-upon libraries):

• once per XX months?
• before every OsmoDevCon?
• once YY items accumulated in TODO-RELEASE file(see TODO-RELEASE file format)
• when configuration/db format changes?

This would help to avoid batching too many changes together and to adhere to RERO better - see 2015-Why-and-HowShould-OpenSource-ProjectsAdopt-Time-Based-Releases.pdf

Versioning considerations for libraries¶

Every osmocom library is built using libtool's version-info system. This system format and algorithm to update the versions is documented in here.

However, debian packaging system follows a different versioning convention, but conveniently the debian versioning system can be deduced from libtool's version-info. More information can be found in here.
Specially interesting is the warning section:

A common mistake is to assume that the three values passed to -version-info map directly into the three numbers at the end of the library name. This is not the case, and indeed, current, revision and age are applied differently depending on the operating system that one is using.
For Linux, for instance, while the last two values map directly from the command-line, the first is calculated by subtracting age from current. On the other hand, on modern FreeBSD, only one component is used in the library version, which corresponds to current.

More related information on the version translation procedure can be found here: [1] [2]

Summary: For libtool's system current:revision:age, it gets translated into version number major.age.revision, where major=current-age, reflecting the fact that ABIs can be backwards compatible. Debian uses major to generate the package name.

The following command, when run on a shared library, will output the name to be used for the Debian package containing that shared library:

objdump -p library.so \
    | sed -n -e's/^[[:space:]]*SONAME[[:space:]]*//p' \
    | LC_ALL=C sed -r -e's/([0-9])\.so\./\1-/; s/\.so(\.|$)//; y/_/-/; s/(.*)/\L&/'

osmocom-release.mk¶

The osmo-release.mk helper (installed by libosmocore-dev) available via make release takes care of

• version bump
• debian/changelog update
• commit
• sign
• tag

Feel free to send patches implementing further automation as you see fit.

You can alternatively run osmo-release.mk directly from your git repo in /foo/bar/libosmocore by using:

PATH="$PATH:/foo/bar/libosmocore" make REL=minor release --include-dir="/foo/bar/libosmocore" 

Dependencies¶

The osmo-release.mk requires several extra dependencies. Make sure you have them installed in your system:

• bumpversion
• git-buildpackage
• devscripts

TODO-RELEASE file format and maintenance¶

• all the strings which contain # considered comment and will be ignored
• actual entries consists of 3 tab-separated fields:
1. library - name of the library affected (should correspond to lib*.pc.in file in project's root directory)
2. what - API or ABI change (used as a guidance to properly bump *_LIBVERSION)
3. description - textual description (will end up in changelog)

When change affecting library's API/ABI is made then new entry should be added to TODO-RELEASE according to the format above. The file will be claned-up automatically by make release command.

How to make a new release¶

First we outline specific steps for different project types, then common part.

• Grep for PKG_CHECK_MODULES in configure.ac, and build with dependencies listed there (check versions after >=). If cannot compile, adjust the versions there so compilation works. eg: osmo-ci.git/scripts/osmo-depcheck.py -w /tmp/depcheck -b -j 8 -u /home/$USER/where-my-local-git-repos-are/ osmo-ggsn
• Adjust dependency versions in debian/control (under Build-Depends) to match those of configure.ac
• Adjust dependency version in contrib/*.spec.in to match those of configure.ac
• Make sure patches under debian/patches still apply correctly.

Extra steps for Libraries¶

Some extra previous steps are required if the project installs a public shared library.

• modify *_LIBVERSION in src/Makefile.am as necessary according to TODO-RELEASE file. Usually the easiest is using git diff $OLD_RELEASE -- include/foobar/ to check API/ABI changes, and implementation changes similarly with git diff $OLD_RELEASE -- src/foobar/
• if necessary ("major = current - age" component of *LIBVERSION was bumped, package name changing as a result) then:
  • Rename debian/lib*.install to match the name change. See Versioning considerations for libraries.
  • Adjust package names in contrib/*.spec.in accordingly.
  • Adjust package names in debian/control accordingly. Specifically look for "Package" and "Depends" attributes.
  • Some projects containing both binaries and libraries (osmo-ggsn, libosmo-sccp) also state the library version in dh_strip lines in debian/rules. That one needs to be updated too to match the new library version.

Upon major libversion change ("old_major" -> "new_major"), the change pattern in general follow this structure:

• "s/${libname}${old_major}/${libname}${new_major}/g"
• "s/${libname}.so.${old_major}/${libname}.so.${new_major}/g"

The release helper is trying to be smart about it and prevent making new library release with non-empty TODO-RELEASE file if *_LIBVERSION is not adjusted beforehand.

Release steps¶

By default make release prepares 'patch' release but you can manually specify any of 'major/minor/patch' as necessary - see http://semver.org/ for details.

• Run git fetch --tags to ensure your local copy of the repository has the latest tags.
• Create a new branch from where you would like to create a new release (master or a previous release) and name it YOURNAME/RELEASE
• Make sure all the manual changes you want in the release commit are staged (git add), (see previous sections about changes needed).
• Run make REL=minor release
• an editor will be opened in case you want to reword the release commit. Useful if you want to add any remarks on the actions taken.
• inspect the latest commit which was just created
• adjust it if necessary and re-sign (see Re-tag new release)
• push commit for review to gerrit and ask somebody to review and merge it quickly (to avoid other commits being merged in between).
  

  $ git push origin HEAD:refs/for/YOURNAME/RELEASE%topic=PROJECT-RELEASE
  

• Once merged, make sure the merged release commit did not change (due to in-between merges), then push the release tag with git push gerrit --tags
• consider preparing article for https://osmocom.org/news/ and sending announcement to appropriate ML for major release once release commit passed the review

In case you want to undo the release commit you did locally:

• git tag -d TAG_JUST_CREATED
• git reset --soft HEAD^
• git restore --staged debian/changelog && git restore debian/changelog
• Do your modifications
• Proceed again with the release steps listed above

In case there is no make release target (e.g. osmo_dia2gsup):

• run gbp dch
• adjust debian/changelog, at least change UNRELEASED to unstable
• commit as "Bump version: 0.1.1" (replace 0.1.1 with new version)
• run git tag -s 0.1.1, put as title "Release 0.1.1"

Which new release to make¶

Use following guidelines when choosing release type:

• major - ?? TBD
• minor - ?? TBD
• patch - ?? TBD

If unsure - ask in corresponding ML.

Deprecation policy¶

Functions/interfaces marked as deprecated for X releases of type Y can be removed in next Z release.

TBD: what's appropriate value for X? which Y and Z (from major/minor/patch) should we use?

How to (re)tag a new release¶

This might be necessary if previous release was made manually with some mistakes which have to be corrected and amended to the release commit.

git tag -s 0.4.0 -f -m "Release v0.4.0 on 2017-08-25." 

This will automatically (re)sign the latest commit. You can specify which commit to sign explicitly.

Say, for example, the git hash is 012342abcdefg and the next open version is 0.1.3:

git tag -s 0.1.3 012342abcdefg -m "release 0.1.3" 

(If gpg complains, see GPG: Have a matching user id.)

Verify that git picks up the new version tag:

$ git describe
0.1.3-3-g1f95179

N. B: For your local build, nothing will change until you delete the .version file and completely rebuild:

rm .version
autoreconf -fi
./configure
make
cat .version

This should show the same as git describe.

When you're convinced that all is in order, push the new tag:

git push origin 0.1.3

If anything went wrong, you can delete the tag (locally) by

git tag -d 0.1.3

and, if you've already pushed it, by

git push --delete origin 0.1.3

GPG: Have a matching user id¶

By default, git tag -s takes your author information to lookup the secret GPG key to sign a tag with.
If the author+email do not exactly match one of the key's @uid@s, you will get this error:

gpg: signing failed: secret key not available

Verify: say, your author+email info in your git config says "John Doe <john@doe.net>", try

gpg --list-secret-keys "John Doe <john@doe.net>" 

If this fails, GPG won't find the right key automatically.

Ways to resolve:

• Use git tag -u <key-id>
• Edit your secret key to add a uid that matches your author information
  

  gpg --edit-key john@doe.net
  gpg> adduid
  # enter details to match the git author
  gpg> save
  

GPG: failed to sign¶

If you are seeing this error:

$ git tag ...
error: gpg failed to sign the data
error: unable to sign the tag

you may need to set this in your terminal's environment:

export GPG_TTY=$(tty)

Furthermore, for headless operation (remote server) it may be necessary to direct the GPG key entry to the terminal.
On debian, make sure the curses key entry is installed:

apt-get install pinentry-curses

and possibly also uninstall other pinentry alternatives, or otherwise make sure it is not trying to launch a graphical pinentry.

Creating a patch release¶

Sometimes we want to create a patch release to apply an important fix to an older major/minor release. Assuming you're in libosmocore and want to create 1.3.1 off 1.3.0, this works as follows ("gerrit" is the remote name here, this might just be "origin" if pulling from gerrit):

1. warning : using the final tag name as the temp branch name is a bad idea because it causes annoying problems like
   

   ❯ git push -d origin 1.3.1      
   error: dst refspec 1.3.1 matches more than one

   
   You need to use git show-ref or git ls-remote to figure out the refspec like refs/heads/1.3.1 to distinguish tag and branch name. Or just use different names!
2. (Locally checkout 1.3.0 as a new branch called rel-1.3.1)
   

   git checkout -b rel-1.3.1 1.3.0
   

3. Create a rel-1.3.1 branch in gerrit
   

   git push gerrit rel-1.3.1:refs/heads/rel-1.3.1
   

4. Do whatever local modifications such as cherry-picking of fixes, ...
5. Perform the release process as outlined above, using 'REL=patch'
   

   make REL=patch release
   

6. Push the changes for review to the rel-1.3.1 branch
   

   git push gerrit HEAD:refs/for/rel-1.3.1
   

7. Perform gerrit review, merge patches in gerrit UI
8. Do git fetch gerrit and make sure your local branch with your tag points to the remote one (eg gitk --all or git show).
9. Push the tag to the repo, after the patches were merged to that branch
   

   git push gerrit 1.3.1
   

10. Remove the temporary branch
    

    git push gerrit :rel-1.3.1
    

Dependency graph¶

This section aims at providing a dependency graph of the osmocom cellular network infrastructure projects in case a cascade of releases is intended: