Release preparation

Feature freeze

Two months before the release (example: DIRAC21), a release branch (example: release-21) is created from master. This is a feature freeze and from this moment on the release branch ideally only receives cosmetics and bugfixes, no major new features, no merges from master or other branches (except cherry-picks; more about it later). You as developer are responsible to commit or merge the to-be-released code to master, before the release branch is created.

Can I commit bleeding edge code to master after the feature freeze?

Yes you can! This is one of the reasons we have the release branch and exactly for this reason we will never merge from master to the release branch, only from the release branch to master.

How to check out the release branch (example release-21 for DIRAC21)

Check out the release branch:

$ git checkout release-21

Now you have it next to master (verify this):

$ git branch

You can switch back to master:

$ git checkout master

And then switch back to the release branch:

$ git checkout release-21

How to commit changes and bugfixes that are relevant for the released code

Commit all such changes to the release branch, not to master. This way no commit or bugfix will get lost. Please do not transfer commits from the release branch to master manually. This is not only unnecessary work but it is harmful (conflicts)! Again, do not commit to master, commit to the release branch:

$ git checkout release-21
$ git pull                      # update the local release-21 branch
$ git commit                    # commit your modifications
$ git push                      # push your changes to release-21 branch
$ git checkout master           # switch to the master branch
$ git merge --no-ff release-21  # merge changes to master, fix conflicts if any
$ git push                      # push your changes to master

Note that by merging your changes to master you might get conflicts. Git points them out clearly. In such cases open conflicting file(s) and fix discrepancies inside manually. They are marked with “<<<<<<” and “>>>>>>” strings.

What if you accidentally committed something to master which belongs to the release? In this case do not merge master to the release branch, but rather cherry-pick the individual commit(s) to the release branch:

$ git checkout release-21
$ git cherry-pick [hash]        # with [hash] that corresponds
                                # to the commit

How to exclude code from being released

Code that is part of master is meant to be part of the next release. There is no mechanism anymore to remove code from master with preprocessing or other scripts. This mechanism got removed when we changed the license to LGPL.

Do not send merge requests towards master for code that you do not with to be released.
As a reviewer, please raise a question if a merge request towards master looks like something that should not be released quite yet.
We will not release any of your private development branches on https://gitlab.com/dirac/dirac-private. Place your code there if you do not wish to release it quite yet.
By sending a merge request towards master you signal that this code is meant to be released.
Do not send merge requests towards master of code written by others without asking them.

Check copyright headers and version

Verify copyright headers.
Verify logo (list of authors).
Bump the version (the version number is kept in file VERSION; but also git grep -i for “orphaned” version numbers in the source code).

Copyright statements and markers

In the development source code you can find the following copyright statement markers:

!dirac_copyright_start
!dirac_copyright_end
!dalton_copyright_start
!dalton_copyright_end
\* dirac_copyright_start \*
\* dirac_copyright_end \*
\* dalton_copyright_start \*
\* dalton_copyright_end \*

They are there so that we do not have to update copyrights manually. You can update them with the maintenance/update_copyright.py script. This script will overwrite whatever is between these markers so it is a bad idea to modify text between the markers manually.

Create the final tarball

In principle we could just let people download the tarball directly from GitLab. However, since we include external code through Git submodules, this has the following disadvantages:

Users would require Git
Tarball is not self-contained and not fully reproducible since we have little control over the external repositories and whether they won’t disappear in few years

For this reason we create a self-contained tarball using the maintenance/create-release-tarball.sh script and this is then the tarball that we upload to Zenodo.

We then direct users to download the tarball from Zenodo and not from GitLab for two reasons:

More self-contained and reproducible
We get download metrics from Zenodo which we would not get from GitLab