Motivation for creating this action was to copy labels from linked issues to the issue / PR which triggered workflow.

This workflow will copy labels from the linked issue for the opened PR.

Github issues can link other issues and this linking is done automatically whenever PR mentions one of the keywords for automated workflows. See documentation

on: 
  pull_request:
    types: [opened]

jobs:
  copy-labels:
    runs-on: ubuntu-latest
    name: Copy labels from linked issues
    steps:
      - name: copy-labels
        uses: michalvankodev/copy-issue-labels@v1
        with:
          repo-token: ${{ secrets.GITHUB_TOKEN }}

There is also support for different workflows to trigger sync of the labels with issue-number parameter

    steps:
      - name: copy-labels
        uses: michalvankodev/[email protected]
        with:
          repo-token: ${{ secrets.GITHUB_TOKEN }}
          issue-number: ${{ github.event.inputs.issue }}

Because GitHub API doesn't provide information about linked issues this workflow will parse the information from the body of the issue.

You can provide custom keywords which will be picked up by the parser.

These keywords will not override github specified keywords.

steps:
  - name: copy-labels
    uses: michalvankodev/copy-issue-labels@v1
    with:
      repo-token: ${{ secrets.GITHUB_TOKEN }}
      custom-keywords: |
        solves
        references