Auto Request Review

A GitHub Action automatically requests review of a pull request based on files changes and/or groups the author belongs to 🤖

Motivation

It varies depending on the team who should review which pull requests. In some teams, review requests are randomly assigned while others prefer to have them reviewed by every one of the team members. With the default features, code review assignments and code owners, you can cover only a couple of use cases - in other words, there are other cases they don't cover.

This GitHub Action best suits any of the following needs:

• You'd like to request review based on files changed
• You'd like to specify reviewers per author
• You'd like to get all of the other team members to review
• You'd like to keep code owners real code owners, not just reviewers
• You'd like to randomly pick reviewers based on the conditions mentioned above

Overall, if you'd like to request review to a certain set of members based on groups and/or files changed, this GitHub Action works best.

Code owners vs reviewers

Code owners own or are responsible for the code in their spaces while reviewers just review it. Some teams distinguish them clearly. For instance, in some teams, you need to get in total two approvals to merge your pull request; one is from one of the code owners and the other is from any of your team members. Another use case is that you'd like certain members to have a look if time permits as an optional and additional review while the code owners have to review it.

Notable Features

This GitHub Action enables you to:

• Auto-assign reviewers based on files changed
• Auto-assign reviewers based on the author
• Auto-assign reviewers based on groups that the author belongs to
• Auto-assign the default reviewers if no reviewers are matched to your rules
• Randomly pick reviewers from matching reviewers
• Request review only in certain conditions

Auto-assign reviewers based on files changed

You can define reviewers based on files using glob expressions.

files:
  '**/*.js':
    - js-lovers

Auto-assign reviewers based on the author

You can specify reviewers per author.

reviewers:
  groups:
    engineers:
      - engineer_a
      - engineer_b

  per_author:
    engineers:
      - engineers
    designer_a:
      - lead_designer
    designer_b:
      - lead_desinger
      - desinger_a

Auto-assign reviewers based on groups that the author belongs to

If you enable the group assignment feature, you can request code review to all of the other members of the groups you belong to.

reviewers:
  groups:
    js-lovers:
      - js-man
      - js-woman

options:
  enable_group_assignment: true

Auto-assign the default reviewers if no reviewers are matched to your rules

You can define the default reviewers who will be assigned when no reviewers are matched to your rules.

reviewers:
  defaults:
    - repository-owners

Randomly pick reviewers from matching reviewers

You can randomly assign reviewers out of those who meet the conditions you set (e.g. file changes, groups, etc.).

options:
  number_of_reviewers: 3

Request review only in certain conditions

If you don't like to have the pull requests considered not yet ready reviewed, you can set ignore_draft and ignored_keywords options.

If your pull request is a draft and ignore_draft is true, review requests won't be made. The same applies if your pull request title contains any of ignored_keywords.

options:
  ignore_draft: true
  ignored_keywords:
    - DO NOT REVIEW

Configuration

You need to prepare two YAML files for:

• Reviewers configuration
• Workflow configuration

Reviewers configuration

Create a configuration file where you can define code reviewers in glob expressions. Internally, minimatch is used as a glob implementation.

The format of a configuration file is as follows:

reviewers:
  # The default reviewers
  defaults:
    - repository-owners # group
    - octocat # username
    - team:default-reviewers # GitHub team

  # Reviewer groups each of which has a list of GitHub usernames
  groups:
    repository-owners:
      - me # username
      - you # username
      - team:owners # GitHub team
    core-contributors:
      - good-boy # username
      - good-girl # username
    js-lovers:
      - js-man # username
      - js-woman # username

  # Reviewers per author.
  # Keys are reviewees, each of which has an array of reviewers.
  per_author:
    engineers:
      - engineers # group
      - team:engineering-managers # GitHub team
    lead_designer:
      - js-lovers # group
      - desinger_a # username
    designer_a:
      - lead_designer # username
    designer_b:
      - lead_desinger # username
      - desinger_a # username

files:
  # Keys are glob expressions.
  # You can assign groups defined above as well as GitHub usernames.
  '**':
    - repository-owners # group
    - team:external-reviewers # GitHub team
  '**/*.js':
    - core-contributors # group
    - js-lovers # group
  '**/*.yml':
    - core-contributors # group
    - yamler # username
  '.github/**':
    - octopus # username
    - cat # username

options:
  ignore_draft: true
  ignored_keywords:
    - DO NOT REVIEW
  enable_group_assignment: false

  # Randomly pick reviewers up to this number.
  # Do not set this option if you'd like to assign all matching reviewers.
  number_of_reviewers: 3

  # If it's true, the last matching files-change pattern takes the most precedence (CODEOWNERS-compatible)
  # See https://github.com/necojackarc/auto-request-review/pull/80 for more details.
  last_files_match_only: false

The default configuration file location is .github/auto_request_review.yml but you can override it in your workflow configuration file.

Workflow configuration

Create a workflow file in .github/workflows (e.g. .github/workflows/auto_request_review.yml):

name: Auto Request Review

on:
  pull_request:
    types: [opened, ready_for_review, reopened]

jobs:
  auto-request-review:
    name: Auto Request Review
    runs-on: ubuntu-latest
    steps:
      - name: Request review based on files changes and/or groups the author belongs to
        uses: necojackarc/[email protected]
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          config: .github/reviewers.yml # Config file location override
          # Look for config locally during run instead of in repo.
          # For instance, if you'd like to use a config file stored in external storage,
          # you can fetch it before you run this action, then let this action pick it up with `use_local: true`.
          # This defaults to false if not specified.
          # See https://github.com/necojackarc/auto-request-review/issues/76 for more details.
          use_local: true
          # Validates that all reviewers inside the config file (e.g. .github/reviewers.yml specified
          # above) have access to be added as reviewers to the repository running this yaml. This
          # can be used similar to native CODEOWNER errors reported by github: 
          # https://docs.github.com/en/rest/repos/repos?apiVersion=2022-11-28#list-codeowners-errors
          #
          # This defaults to false if not specified.
          validate_all: true

(Optional) GitHub Personal Access Token

When the default GITHUB_TOKEN doesn't have the necessary permissions, you need to create a new GitHub personal access token (PAT).

For instance, if you'd like to use GitHub teams to specify reviewers, you need to make a new PAT because the default GITHUB_TOKEN doesn't have the permission to request a review from a team.

The PAT needs to have the repo scope and the account the PAT belongs to needs to have the write permission to the repository. Once you create a new PAT, set it as a secret in your repository.

Let's say you have a @your-awesome-org/happy-team team and make a new secret PAT_FOR_AUTO_REQUEST_REVIEW with your PAT, the configurations files will look like:

files:
  '**':
    - team:happy-team # GitHub team

        with:
          token: ${{ secrets.PAT_FOR_AUTO_REQUEST_REVIEW }}

Working with Forks

By default, forks do not have write access or permissions with workflows. However, for workflows that need write access to do menial tasks like make comments or add reviewers, the pull_request_target trigger can be used. This trigger gives forks write access for the workflows. You can read more about the pull_request_target trigger here.

The pull_request_target trigger works for both native branches as well as forks.

name: Auto Request Review

on:
  pull_request_target:

Dependabot compatibility

Note that with the recent change to GitHub Actions that are created by Dependabot, the pull_request event will no longer give access to your secrets to this action. Instead you will need to use the pull_request_target event. If you do this make sure to read Keeping your GitHub Actions and workflows secure: Preventing pwn requests to understand the risks involved.

Reviewer Access and Private Repos

The reviewer aliases defined in the configurations must have been given access to the repo in order to be added as a code reviewer to the pull request.

If the action attempts to assign a reviewer that does not have access to the repo, a comment will be automatically addded to the pull request to notify the author that not everyone was assigned.

The following reviewers did not have access to be added as reviewers, please review their access:

Individual Alias
    - jamoor-test-twice

Team Alias
    - fake-team-super-stale

Comment added by Auto Reviewer Robot 🤖: <Base64 Unique ID>

If the action is re-run post an administrator giving access to the aliases, or the aliases are removed from the config yaml file, the action will update the comment to notify that all issues have been resolved.

All reviewer issues have been resolved!
Comment added by Auto Reviewer Robot 🤖: <Base64 Unique ID>