GitHub Action to assign a reviewer by comment command.

• This works as GitHub Actions.
• This assigns a reviewer and change a label by special comment command.
• This behaves like highfive or popuko

Motivation

• We don't manage any bot instance for this purpose.
• We'd like to use managed service to host this kind of a bot.
• Try GitHub Actions :)
  • Investigate its latency & its throughput for chat bot purpose.

Special Command List

• You can use these command as a comment for issue or pull request or pull request review.
• Your comment change some status of the issue you commented.
• This actions treats S- prefixed labels exclusively.
  • e.g. If your pull request is labeled with S-a and S-b, then this action replaces them with S-c.
• If your comment has multiple line, this action interprets only the first line of it.
• To support the command style which bors-ng uses, you can write botname <this action command>.
  • e.g. bors r+ is ok.

r? @username1 @username2

• This assigns @username1 and @username2 to assignees filed.
• This adds the label S-awaiting-review.

r+ or r=username1, username2

• This assigns the user who opens the issue to assignees filed.
• This adds the label S-awaiting-merge.

r-

• This assigns the user who opens the issue to assignees filed.
• This adds the label S-need-code-change.

Setup

Add this example to your GitHub Actions workflow configuration.

YAML syntax

name: assign_review_by_comment by issue_comment
on: [issue_comment, pull_request_review]

jobs:
  assign_review_by_comment:
    runs-on: ubuntu-latest
    steps:
    - name: assign_review_by_comment
      # We recommend to use an arbitary latest version
      # if you don't have any troubles.
      # You can also specify `master`, but it sometimes might be broken.
      uses: cats-oss/github-action-auto-assign@v2
      env:
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

Limitations

• By the Limitation of the current GitHub Actions, this might not works your repository well.
  • Because GitHub Actions is still in beta.
  • We confirms this works with a private repository. But we have not confirmed yet to work with a public one.

Known Problems

This action could not interact with my comment in a few seconds.

• We know that this action takes ~30sec to react user comment.
• We think this is the current or fundamental limitation of GitHub Actions. See #6.