action.yml

name: 'Comment Pull Request for workflow'
description: 'A GitHub Action for commenting on pull requests from workflows.'
author: 'YUMEMI Inc.'
branding:
  icon: 'message-circle'
  color: 'blue'
inputs:
  comment:
    description: 'Comment text.'
    required: true
  comment-if-failure:
    description: 'Comment text to be used with priority when job status is failure. If not specified, normal comment will be used.'
    required: false
  grouping-key:
    description: 'Key to group comments. Comments from the same group are deleted, hidden, or edited.'
    required: false
    default: '${{ github.workflow }}-${{ github.job }}'
  previous-comment:
    description: 'One of delete, hide, edit, or keep. See README for details.'
    required: false
    default: 'delete'
  pull-request-number:
    description: 'Target pull request number.'
    required: false
    default: ${{ github.event.pull_request.number }}
  sha:
    description: 'Commit SHA used to search for pull request number.'
    required: false
    default: ${{ github.sha }}
runs:
  using: 'composite'
  steps:
    - name: Comment
      shell: bash
      env:
        COMMENT: ${{ job.status == 'failure' && inputs.comment-if-failure || inputs.comment }}
        TAG: '<comment-pull-request:${{ inputs.grouping-key }}>'
        PREVIOUS_COMMENT: ${{ inputs.previous-comment }}
        PR_NUMBER: ${{ inputs.pull-request-number }}
        SHA: ${{ inputs.sha }}        
        GH_REPO: ${{ github.repository }} # for GitHub CLI
        GH_TOKEN: ${{ github.token }} # for GitHub CLI
        IS_VALID_PREVIOUS_COMMENT: ${{ inputs.previous-comment != null && contains(fromJSON('["delete","hide","edit","keep"]'), inputs.previous-comment) }}
      run: |
        echo "::debug::gh version: $(gh --version | tr '\n' ' ')"
        echo "::debug::jq version: $(jq --version)"
        source "$GITHUB_ACTION_PATH/raise_error.sh"

        if [ -z "$COMMENT" ]; then raise_error "Specify 'comment' or 'failure-comment' input."; fi

        if [ "$IS_VALID_PREVIOUS_COMMENT" != 'true' ]; then raise_error "'previous-comment' input must be one of delete, hide, edit, or keep."; fi

        # have pemisson?
        gh api repos/{owner}/{repo}/pulls --silent > /dev/null 2>&1 || raise_permission_error

        # get pull request number
        if [ -n "$PR_NUMBER" ]; then
          # valid pull request number?
          gh api "repos/{owner}/{repo}/pulls/$PR_NUMBER" --silent > /dev/null 2>&1 || raise_error "'pull-request-number' input is not valid."
          pr_number="$PR_NUMBER"
        else
          if [ -n "$SHA" ]; then
            number="$(gh api "repos/{owner}/{repo}/commits/$SHA/pulls" | jq '.[0].number')" > /dev/null 2>&1 || raise_error "'sha' input is not valid."
            if [[ -n "$number" && "$number" != 'null' ]]; then
              pr_number="$number"
            else
              raise_error "Specify 'pull-request-number' input or specify 'sha' input related to pull request."
            fi
          else
            raise_error "Specify 'pull-request-number' input or 'sha' input."
          fi
        fi

        # on windows, jq's return contains CR
        comments="$(gh api "repos/{owner}/{repo}/issues/$pr_number/comments" --paginate | jq --arg tag "$TAG" 'reverse|.[]|select(.body|contains($tag))' | tr -d '\r')"
        ids="$(echo "$comments" | jq '.id' | tr -d '\r')"
        node_ids="$(echo "$comments" | jq -r '.node_id' | tr -d '\r')"

        if [[ "$PREVIOUS_COMMENT" == 'delete' && -n "$ids" ]]; then
          IFS=$'\n'
          for id in $ids ; do
            gh api --method DELETE "repos/{owner}/{repo}/issues/comments/$id" --silent > /dev/null 2>&1 || raise_permission_error
          done
        fi

        if [[ "$PREVIOUS_COMMENT" == 'hide' && -n "$node_ids" ]]; then
          IFS=$'\n'
          for node_id in $node_ids ; do
            gh api graphql -f subjectId="$node_id" -f query='
              mutation($subjectId:ID!) {
                minimizeComment(input: { subjectId: $subjectId, classifier: OUTDATED }) {
                  minimizedComment { isMinimized }
                }
              }
            ' --silent > /dev/null 2>&1 || raise_permission_error
          done
        fi

        comment="$(echo -e "<!-- $TAG -->\n\n$COMMENT")"

        if [[ "$PREVIOUS_COMMENT" == 'edit' && -n "$ids" ]]; then
          last_id="$(echo "$ids" | head -1)"
          gh api --method PATCH "repos/{owner}/{repo}/issues/comments/$last_id" -f "body=$comment" --silent > /dev/null 2>&1 || raise_permission_error
        else
          gh api --method POST "repos/{owner}/{repo}/issues/$pr_number/comments" -f "body=$comment" --silent > /dev/null 2>&1 || raise_permission_error
        fi