azjezz / automatic-releases

Automated release process for `laminas/` projects, usable as github action

Release Automation

This project is a Github Action that allows maintainers of open-source projects that follow SemVer to automate the automation of releases.

Installation

To use this automation in your own repository, copy the examples/.github workflows into your own project:

cd /tmp
git clone https://github.com/laminas/automatic-releases.git
cd /path/to/your/project
mkdir -p .github/workflows
# Copy selected flow that fits for your project
cp /tmp/automatic-releases/examples/.github/release-on-milestone-closed.yml .github/workflows
# ... or:
cp /tmp/automatic-releases/examples/.github/release-on-milestone-closed-triggering-release-event.yml .github/workflows
git add .github/workflows
git commit -m "Added release automation"

To get started you need to create a branch for the next release. e.g. if your next milestone will be 3.2.0 a 3.2.x branch is required.

Then add following secrets to your project or organization:

Secret	Description
GIT_AUTHOR_NAME	full name of the author of your releases: can be the name of a bot account.
GIT_AUTHOR_EMAIL	email address of the author of your releases: can be an email address of a bot account.
SIGNING_SECRET_KEY	a password-less private GPG key in ASCII format, to be used for signing your releases: please use a dedicated GPG subkey for this purpose. Unsigned releases are not supported, and won't be supported. See Setting up GPG keys below for help.
ORGANIZATION_ADMIN_TOKEN	You have to provide an ORGANIZATION_ADMIN_TOKEN (with a full repo scope), which is a github token with administrative rights over your organization (or regular user project, for non-organization projects), issued by a user that has administrative rights over your project (that's you, if it is your own non-organization repository). This is required for the laminas:automatic-releases:switch-default-branch-to-next-minor command, because changing default branch of a repository currently requires administrative token rights. You can generate a token from your personal access tokens page.

The GITHUB_TOKEN secret you see in the examples is automatically created for you when you enable GitHub Actions. To learn more about how it works, read "Authenticating with the GITHUB_TOKEN" in the GitHub Docs.

Setting up GPG keys

Using a subkey from an existing GPG key

First open your master key for editing (use --list-keys to find it):

gpg --edit-key "<YOUR MASTER KEY ID>"

Type addkey and select a type that is for signing, you might be asked about bit size depending on your choice. When deciding over key expire, avoid setting to never expire, as recommendation of key bits will change over time. Type save to persist the new subkey to your master key. Make a note of the Key ID as you will need it in the next step.

Next export the new sub key:

gpg --output private.key --armor --export-secret-subkeys "<SubKey ID>!"

This will be exported to the file private.key. The ! at the end is important as it limits the export to just the sub key

Delete the file once you are done and don't share it with anyone else

If your master key is password protected, you will need to remove the password from the subkey before you can add it into github settings. You can skip this if your master key is not password protected.

To remove the password from the subkey, create an ephemeral gpg home directory:

install -d -m 700 gpg-tmp

Ensure that it works with gpg:

gpg --homedir gpg-tmp --list-keys

Import your subkey:

gpg --homedir gpg-tmp --import private.key

Enter edit mode:

gpg --homedir gpg-tmp --edit-key <SubKey ID>

Type passwd, entering your current password and then set the password to "" to remove it.

The command may give error error changing passphrase: No secret key when setting empty password. You should ignore it as the password was really removed.

Type save to exit edit mode and re-export your subkey:

gpg --homedir gpg-tmp --output private.key --armor --export-secret-subkeys "<SubKey ID>!"

Finally, remove the ephemeral directory:

rm --rf gpg-tmp

You will now need to export your master public key with the new subkey public key to the file public.key:

gpg --output public.key --armor --export <YOUR MASTER KEY ID>

Then republish it to anywhere that you currently publish your public keys.

Using a new key

To generate a new GPG key use the following command:

gpg2 --full-generate-key

Pick option 4, then type 4096 for key size, select your desired expiry. Fill out the user information and leave the password blank.

Once generated it will output something like gpg: key <Key ID> marked as ultimately trusted. Take a note of this Key Id to use in the next step.

Now output the key to the file private.key in the correct format to put into the environment variable required for setup:

gpg --output private.key --armor --export-secret-key <Key ID>

Delete the file once you are done and don't share it with anyone else

Optionally, you can export the corresponding public key to the file public.key:

gpg --output public.key --armor --export <Key ID>

You can publish this key on your project webpage to allow users to verify your signed releases. You could sign this new key with your personal key and the keys of other project maintainers to establish its provenance.

Usage

Assuming your project has Github Actions enabled, each time you close a milestone, this action will perform all following steps (or stop with an error):

1. determine if all issues and pull requests associated with this milestone are closed
2. determine if the milestone is named with the SemVer x.y.z format
3. create a changelog by looking at the milestone description and associated issues and pull requests
4. select branch x.y.z for the release (e.g. 1.1.x for a 1.1.0 release)
5. create a tag named x.y.z on the selected branch, with the generated changelog
6. publish a release named x.y.z, with the generated tag and changelog
7. create (if applicable), a pull request from the selected branch to the next release branch
8. create (if necessary) a "next minor" release branch x.y+1.z
9. switch default repository branch to newest release branch

Please read the feature/ specification for more detailed scenarios on how the tool is supposed to operate.

Branching model

In this model we operate with release branches (e.g. 1.0.x, 1.1.x, 1.2.x). This provides a lot of flexibility whilst keeping a single workflow.

Working on new features

The current default release branch should be used. The default branch is always automatically changed after a new release is created.

An example is Mezzio that has 3.2.x as the current default release branch for simple features and deprecation notices and 4.0.x for the next major release.

Working on bug fixes

Bug fixes should be applied on the version which introduced the issue and then synchronized all way to the current default release branch via merge-ups.

Releasing

When releasing a new version x.y.z, a new branch will be created x.y+1.z and will be set as the next default release branch. If a hotfix x.y.z+1 is released, a merge-up branch is automatically created.

Synchronizing branches

To keep branches synchronized merge-ups are used.

That consists in getting the changes of a specific released branch merged all the way up to the current default branch. This ensures that all release branches are up-to-date and will never present a bug which has already been fixed. Merge-up branches are automatically created but needs to be merged manually into the targeted branch.

Example

Let's say we've released the versions 1.0.0 and 1.1.0. New features are being developed on 1.2.x. After a couple weeks, a bug was found on version 1.0.0.

The fix for that bug should be done based on the branch 1.0.x and, once merged, the branches should be updated in this way:

1. Create a PR for the automatically created branch 1.0.x-merge-up-into-1.1.x_*, using 1.1.x as destination.
2. Merge the new PR into 1.1.x.
3. Create a PR for the automatically created branch 1.1.x-merge-up-into-1.2.x_*, using 1.2.x as destination.
4. Merge the new PR into 1.2.x.

⚠️ when the merge-up can't be merged due to conflicts, it needs to be synced with the destination branch. That's done by merging the destination into the merge-up branch and resolving the conflicts locally:

1. Update your local repository (git fetch origin)
2. Checkout to merge-up branch (git checkout 1.1.x-merge-up-into-1.2.x_*)
3. Sync merge-up branch (git merge --no-ff origin/1.2.x)
4. Solve conflicts (using git mergetool or through an IDE)
5. Resume merge (git merge --continue)
6. Push (git push)

If needed you can create a merge-up branch manually: git checkout 1.0.x && git checkout -b 1.0.x-merge-up-into-1.1.x

Triggering release workflow events

Because the tokens generated by GitHub Actions are considered OAuth tokens, they are incapable of triggering further workflow events (see this document for an explanation).

As such, if you want to trigger a release event when automatic-releases runs, you will need to modify your .github/workflows/release-on-milestone-closed.yml file to assign the ORGANIZATION_ADMIN_TOKEN as the value of the GITHUB_TOKEN environment variable for the Release step:

    - name: "Release"
      uses: "./"
      with:
        command-name: "laminas:automatic-releases:release"
      env:
        "GITHUB_TOKEN": ${{ secrets.ORGANIZATION_ADMIN_TOKEN }}