[llvm-dev] RFC: New Automated Release Workflow (using Issues and Pull Requests)

[Tom Stellard via llvm-dev]

On 12/17/21 13:15, Tom Stellard wrote:
> Hi,
> 
> Here is a proposal for a new automated workflow for managing parts of the release
> process.  I've been experimenting with this over the past few releases and
> now that we have migrated to GitHub issues, it would be possible for us to
> implement this in the main repo.
> 
> The workflow is pretty straight forward, but it does use pull requests.  My
> idea is to enable pull requests for only this automated workflow and not
> for general development (i.e. We would still use Phabricator for code review).
> Let me know what you think about this:
> 

Hi,

Thanks for the feedback on this.  I've posted a patch to implement this proposal:
https://reviews.llvm.org/D117386.  The only change is that the pull requests will
not be in the llvm/llvm-project repo, but will instead be in llvmbot/llvm-project.
This will reduce the number of notifications and avoid confusion about whether or
not we are using pull requests for this project.

-Tom

> 
> # Workflow
> 
> * On an existing issue or a newly created issue, a user who wants to backport
> one or more commits to the release branch adds a comment:
> 
> /cherry-pick <commit_sha> <..>
> 
> * This starts a GitHub Action job that attempts to cherry-pick the commit(s)
> to the current release branch.
> 
> * If the commit(s) can be cherry-picked cleanly, then the GitHub Action:
>      * Pushes the result of the cherry-pick to a branch in the
>        llvmbot/llvm-project repo called issue<n>, where n is the number of the
>        GitHub Issue that launched the Action.
> 
>      * Adds this comment on the issue: /branch llvmbot/llvm-project/issue<n>
> 
>      * Creates a pull request from llvmbot/llvm-project/issue<n> to
>        llvm/llvm-project/release/XX.x
> 
>      * Adds a comment on the issue: /pull-request #<n>
>        where n is the number of the pull request.
> 
> * If the commit(s) can't be cherry-picked cleanly, then the GitHub Action job adds
> the release:cherry-pick-failed label to the issue and adds a comment:
> "Failed to cherry-pick <commit_sha> <..>" along with a link to the failing
> Action.
> 
> * If a user has manually cherry-picked the fixes, resolved the conflicts, and
> pushed the result to a branch on github, they can automatically create a pull
> request by adding this comment to an issue: /branch <user>/<repo>/<branch>
> 
> * Once a pull request has been created, this launches more GitHub Actions
> to run pre-commit tests.
> 
> * Once the tests complete successfully and the changes have been approved
> by the release manager, the pull request can me merged into the release branch.
> 
> * After the pull request is merged, a GitHub Action automatically closes the
> associated issue.
> 
> Some Examples:
> 
> Cherry-pick success: https://github.com/tstellar/llvm-project/issues/729
> Cherry-pick failure: https://github.com/tstellar/llvm-project/issues/730
> Manual Branch comment: https://github.com/tstellar/llvm-project/issues/710
> 
> 
> # Motivation
> 
> Why do this?  The goal is to make the release process more efficient and transparent.
> With this new workflow, users can get automatic and immediate feedback when a commit
> they want backported doesn't apply cleanly or introduces some test failures.  With
> the current process, these kinds of issues are communicated by the release manager,
> and it can be days or even weeks before a problem is discovered and communicated back
> to the users.
> 
> Another advantage of this workflow is it introduces pre-commit CI to the release branch,
> which is important for the stability of the branch and the releases, but also gives
> the project an opportunity to experiment with new CI workflows in a way that
> does not disrupt development on the main branch.
> 
> # Implementation
> 
> If this proposal is accepted, I would plan to implement this for the LLVM 14 release cycle based
> on the following proof of concept that I have been testing for the last few releases:
> 
> https://github.com/tstellar/llvm-project/blob/release-automation/.github/workflows/release-workflow.yml
> https://github.com/tstellar/llvm-project/blob/release-automation/.github/workflows/release-workflow-create-pr.yml
> https://github.com/tstellar/llvm-project/blob/release-automation/.github/workflows/release-merge-pr.yml
> 
> Thanks,
> Tom