A GitHub action that lets code-owners merge PRs via a comment.

This action uses the standardized structure of a CODEOWNERS file to handle the access controls.

A simple example

So, with this file at: .github/CODEOWNERS:

README.md @orta

If a PR contained only a change to the README.md - this action would say that "@orta has the ability to merge by commenting 'LGTM'".

Then, when/if this happens the GitHub Action will merge for you.

A real-world example

.github/CODEOWNERS:

# Collaborators for Japanese Translation of the Website
packages/playground-examples/copy/ja/**/*.md @sasurau4 @Quramy @Naturalclar @Takepepe @orta
packages/tsconfig-reference/copy/ja/**/*.md @sasurau4 @Quramy @Naturalclar @Takepepe @orta
packages/typescriptlang-org/src/copy/ja/**/*.md @sasurau4 @Quramy @Naturalclar @Takepepe @orta
packages/documentation/copy/ja/**/*.ts @sasurau4 @Quramy @Naturalclar @Takepepe @orta

This allows any of @sasurau4, @Quramy, @Naturalclar, @Takepepe or @orta to merge PRs which affect their areas of the translation process in the TypeScript Website repo. Code owners can use a review, or a comment to merge.

Setting It Up

You want a unique workflow file, e.g. .github/workflows/codeowners-merge.yml

name: Codeowners merging
on:
  pull_request_target: { types: [opened] }
  issue_comment: { types: [created] }
  pull_request_review: { types: [submitted] }

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v4
      - name: Run Codeowners merge check
        uses: javalin/codeowner-selfmerge-action@master
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Then you should be good to go. No version releases are made, so you can use @master to get the latest version or use a specific commit hash.

Security

We force the use of pull_request_target as a workflow event to ensure that someone cannot change the CODEOWNER files at the same time as having that change be used to validate if they can merge.

Issue / PR manipulation

Merging a PR has strict security requirements, but closing a PR or Issue can have a weaker one. Anyone with a GitHub login in the CODEOWNER has the ability to close any PR / Issue via a comment/review which includes:

@github-actions close

A closed PR can be re-opened with:

@github-actions reopen

Extras

You can use this label to set labels for specific sections of the codebase, by having square brackets to indicate labels to make: [label]

# Collaborators for Spanish Translation of the Website
packages/playground-examples/copy/es/**/*.md @KingDarBoja [translate] [es]
packages/playground-examples/copy/es/**/*.ts @KingDarBoja [translate] [es]
packages/tsconfig-reference/copy/es/**/*.md @KingDarBoja [translate] [es]
packages/typescriptlang-org/src/copy/es/**/*.ts @KingDarBoja [translate] [es]
packages/documentation/copy/es/**/*.ts @KingDarBoja [translate] [es]

Config

There are five options available at the moment:

• cwd, which can be used to determine the root folder to look for CODEOWNER files in.
• merge_method, which can be merge , squash (default) or rebase, depending on what you want the action to do.
• quiet - does not output a message saying who can merge PRs

- name: Run Codeowners merge check
  uses: javalin/codeowner-selfmerge-action@master
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  with:
    cwd: './docs'
    merge_method: 'squash'

Then 2 for handling fallbacks on PRs which aren't able to be maintained by anyone in the CODEOWNERs:

• if_no_maintainers_add_label - A label to add which denotes it is a maintainers PR to handle
• if_no_maintainers_assign - A string of @ prefixed GitHub usernames, separated by spaces which denotes who should be assigned to PRs which don't get a CODEOWNER.

- name: Run Codeowners merge check
  uses: javalin/codeowner-selfmerge-action@master
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  with:
    merge_method: 'squash'
    if_no_maintainers_add_label: 'maintainers'
    if_no_maintainers_assign: '@orta @sandersn'

Dev

Use npx jest --watch to run tests.

Deploy

Use the GH UI to make a tag and release.