Re: GitHub Pull Request based Code Review Process

Michael D Kinney


I have added the following repository to TianoCore to
support the evaluation of the GitHub pull request based
code review process and the email archive webbook. This
is a copy of tianocore/edk2 repo as of May 10, 2020.

I have updated Maintainers.txt in this repo to add
GitHub IDs for the maintainers and reviewers. Please
review these updates to make sure they are correct.

There are a few maintainers and reviewers that I need
GitHub IDs. Please send me your GitHub IDs and I will
complete the update of Maintainers.txt.

M: Chao Zhang <chao.b.zhang@...>
R: Julien Grall <julien@...>
R: Marc-André Lureau <marcandre.lureau@...>
R: Stefan Berger <stefanb@...>
R: Liran Alon <liran.alon@...>
R: Nikita Leshenko <nikita.leshchenko@...>



-----Original Message-----
From: Kinney, Michael D <michael.d.kinney@...>
Sent: Friday, May 8, 2020 8:00 PM
To:;; Kinney,
Michael D <michael.d.kinney@...>
Subject: [edk2-rfc] GitHub Pull Request based Code
Review Process


This is a proposal to change from the current email-
based code review process to
a GitHub pull request-based code review process for all
repositories maintained
in TianoCore. The current email-based code review
process and commit message
requirements are documented in or Readme.rst
at the root of
repositories along with a few Wiki pages:


The goal is to post changes by opening a GitHub pull
request and perform all
code review activity using the GitHub web interface.
This proposal does not
change any licenses or commit message requirements. It
does require all
developers, maintainers, and reviewers to have GitHub

One requirement that was collected from previous
discussions on this topic is
the need for an email archive of all patches and code
review activities. The
existing GitHub features to produce an email archive
were deemed insufficient.
A proof of concept of a GitHub webhook has been
implemented to provide the email
archive service. This email archive is read-only. You
will not be able to send
emails to this archive or reply to emails in the

The sections below provide more details on the proposed
GitHub pull request
based code review process, details on the email archive
service, and a set of
remaining tasks make the email archive service
production quality. It does not
make sense to support both the existing email-based
code review and the GitHub
pull request-based code review at the same time.
Instead, this proposal is to
switch to the GitHub pull request-based code review and
retire the email based
code review process on the same date.

The edk2 repository is using GitHub pull requests today
to run automated
CI checks on the code changes and allows a maintainer
to set the `push` label to
request the changes to be merged if all CI checks pass.
With this proposal,
once the code review is complete and the commit
messages have been updated, the
same pull request can be used to perform a final set of
CI checks and merge the
changes into the master branch.

I would like to collect feedback on this proposal and
the email archive service
over the next two weeks with close of comments on
Friday May 22, 2020. If all
issues and concerns can be addressed, then I would like
to see the community
agree to make this change as soon as all remaining
tasks are completed.

# TianoCore Repositories to enable

* [edk2](
* [edk2-platforms](
* [edk2-non-osi](
* [edk2-test](
* [edk2-libc](
* [edk2-staging](

# GitHub Pull Request Code Review Process

**NOTE**: All steps below use
[edk2]( as an
example. Several repositories are supported.

## Author/Developer Steps
* Create a personal fork of

* Create a new branch from edk2/master in personal
fork of edk2 repository.

* Add set of commits for new feature or bug fix to
new branch. Make sure to
follow the commit message format requirements. The
only change with this
RFC is that the Cc: lines to maintainers/reviewers
should **not** be added.
The Cc: lines are still supported, but they should
only be used to add
reviewers that do not have GitHub IDs or are not
members of TianoCore.

* Push branch with new commits to personal fork
* Create a pull request against TianoCore edk2/master

* If pull request has more than 1 commit, then fill
in the pull request title
and decryption information for Patch #0. Do not
leave defaults.

* Do not assign reviewers. The webhook assigns
maintainers and reviewers to
the pull request and each commit in the pull

* If maintainers/reviewers provide feedback that
requires changes, then make
add commits to the current branch with the
requested changes. Once all
changes are accepted on the current branch,
reformulate the patch series and
commit comments as needed for perform a forced push
to the branch in the
personal fork of the edk2 repository. This step
may be repeated if multiple
versions of the patch series are required to
address all code review

**OPEN**: How should minimum review period be set?

## TianoCore GitHub Email Archive Webhook Service Steps
* Receive an event that a new pull request was opened
* Evaluate the files modified by the entire pull
request and each commit in
the pull request and cross references against
`Maintainters.txt` in the root
of the repository to assign maintainers/reviewers
to the pull request and
each commit in the pull request. Individual commit
assignments are performed
by adding a commit comment of the following form:

[CodeReview] Review-request @mdkinney

* Generate and sends git patch review emails to the
email archive. Emails
are also sent to any Cc: tags in the commit

* If the author/developer performs a forced push to
the branch in their
personal fork of the edk2 repository, then a new
set of patch review emails
with patch series Vx is sent to the email archive
and any Cc: tags in commit

* Receive events associated with all code review
activities and generate
and send emails to the email archive that shows all
review comments and
all responses closely matching the email contents
seen in the current email
based code review process.

* Generate and send email when pull request is merged
or closed.

## Maintainer/Reviewer Steps

* Make sure GitHub configuration is setup to 'Watch'
the repositories that
you have maintainer ship or review responsibilities
and that email
notifications from GitHub are enabled. This
enables email notifications
when a maintainer/reviewer is assigned to a pull
request and individual

* Subscribe to the email archive associated with the
TianoCore GitHub Email
Archive Webhook Service.

* Review pull requests and commits assigned by the
TianoCore GitHub Email
Archive Webhook Service and use the GitHub web UI
to provide all review

* Wait for Author/Developer to respond to all
feedback and add commits with
code changes as needed to resolve all feedback.
This step may be repeated
if the developer/author need to produce multiple
versions of the patch
series to address all feedback.

* Once all feedback is addressed, add Reviewed-by,
Acked-by, and Tested-by
responses on individual commits. Or add Series-
reviewed-by, Series-acked-by,
or Series-Tested-by responses to the entire pull

* Wait for Developer/Author to add tags to commit
messages in the pull request.

* Perform final review of patches and commit message
tags. If there are not
issues, set the `push` label to run final set of CI
checks and auto merge
the pull request into master.

# Maintainers.txt Format Changes

Add GitHub IDs of all maintainers and reviewers at the
end of M: and R: lines
in []. For example:

M: Michael D Kinney <michael.d.kinney@...>

# TianoCore GitHub Email Archive Webhook Service

Assign reviewers to commits in a GitHub pull request
based on assignments
documented in Maintainers.txt and generates an email
archive of all pull request
and code review activities.

# Email Archive Subscription Service

The emails are being delivered to the following RedHat
email subscription
service. Please subscribe to receive the emails and to
be able to view the
email archives.

The email archives are at this link:

The following sections show some example pull requests
and code reviews to
help review the generated emails, their contents, and

## Email Achieve Thread View

## Example patch series with 1 patch

## Example patch series with < 10 patches


## Example patch series with > 80 patches


# Tasks to Complete

* Create edk2-codereview repository for evaluation of
new code review process.
* Add GitHub IDs to Maintainers.txt in edk2-codereview
* Update BaseTools/Scripts/ to be
compatible with GitHub IDs at
the end of M: and R: statements
* Update webhook to use Rabbit MQ to manage requests
and emails
* Determine if webhook requests must be serialized?
Current POC is serialized.
* Make sure webhook has error handling for all
unexpected events/states.
* Add logging of all events and emails to webhook
* Add admin interface to webhook
* Deploy webhook on a production server with 24/7

# Ideas for Future Enhancements

* Run before assigning
* Add a simple check that fails if a single patch spans
more than one package.
* Monitor comments for Reviewed-by, Acked-by, Tested-
by, Series-Reviewed-by,
Series-Acked-by, Series-Tested-by made by assigned
Once all commits have required tags, auto update
commit messages in the
branch and wait for maintainer to set the `Push`
label to run CI and auto
merge if all CI checks pass.

Best regards,


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