GitHub Action to synchronise forks

Table of Contents

• Example Workflow file
• Inputs
• GitHub Token
  • Pull from public repository and push to current repository
  • Pull from private repository and/or push to other repository
• Example: Update multiple branches
• License
• No affiliation with GitHub Inc.

Example Workflow file

jobs:
  update_external_airflow_fork:
    runs-on: ubuntu-latest
    steps:
      - uses: TobKed/github-forks-sync-action@master
        with:
          github_token: ${{ secrets.GH_PERSONAL_ACCESS_TOKEN }}
          upstream_repository: apache/airflow
          target_repository: TobKed/airflow
          upstream_branch: master
          target_branch: master
          force: true
          tags: true

Inputs

name	value	default	description
github_token	string		Token for the repo. Can be passed in using ${{ secrets.GITHUB_TOKEN }}.
upstream_repository	string		Repository name. If you want to pull from private repository, you should make a personal access token and use it as the github_token input.
target_repository	string		Repository name. Default or empty repository name represents current github repository. If you want to push to other repository, you should make a personal access token and use it as the github_token input.
upstream_branch	string	'master'	Source branch from which changes will be pushed.
target_branch	string	'master'	Destination branch to push changes.
force	boolean	false	Determines if force push is used.
tags	boolean	false	Determines if --follow-tags --tags is used.

GitHub Token

GitHub Token is required to authenticate operations on the repository/repositories. It should be stored as a secret. To learn more about creating and using secrets check the official docs.

Pull from public repository and push to current repository

GitHub automatically creates a GITHUB_TOKEN secret to use in your workflow. You can use the GITHUB_TOKEN to authenticate in a workflow run. github_token input can be passed in as ${{ secrets.GITHUB_TOKEN }}. To learn more about this secret check the official docs.

Pull from private repository and/or push to other repository

Create Personal Access Token (PAT) with repo permissions and store it as a secret. Then it can be passed as in the example below:

github_token: ${{ secrets.GH_PERSONAL_ACCESS_TOKEN }}

To learn more about this creating PAT check the official docs.

Example: Update multiple branches

To update multiple branches you can use matrix to parametrize it (Create a build matrix and define variations for each job - GitHub Docs).

name: Sync all branches
on:
  workflow_dispatch:

jobs:

  generate-matrix:
    name: Generate matrix of branches
    runs-on: ubuntu-latest
    outputs:
      matrix: ${{ steps.set-matrix.outputs.matrix }}
    steps:
      - name: Set matrix of branches
        id: set-matrix
        run: |
          upstream_repo="https://${GITHUB_ACTOR}:${INPUT_GITHUB_TOKEN}@github.com/${INPUT_UPSTREAM_REPOSITORY}.git"

          # these jq scripts will produce the same matrix jobs by default
          # choose the one that works for any additional values that you may need to build your matrix with
          jq_script='{ "branch": [inputs | split("\n") | .[] | gsub(".*refs/heads/"; "")] }'   # {"branch":["$branch_name_1","$branch_name_2"]}
          # jq_script='[inputs | split("\n") | .[] | gsub(".*refs/heads/"; "") | { "branch": . }]' # [{"branch":"$branch_name_1"},{"branch":"$branch_name_2"}]

          JSON="$(git ls-remote --heads "$upstream_repo" | jq -McnR "$jq_script")"

          # debug matrix pretty json formatted output
          jq --monochrome-output . -- <<< "$JSON"

          # set output variable named 'matrix' for use in subsequent jobs that 'needs' this job.
          # https://docs.github.com/en/actions/using-jobs/defining-outputs-for-jobs
          echo "::set-output name=matrix::$JSON"

        env:
          INPUT_GITHUB_TOKEN: ${{ secrets.GH_PERSONAL_ACCESS_TOKEN }}
          INPUT_UPSTREAM_REPOSITORY: apache/airflow

  update_external_airflow_fork:
    runs-on: ubuntu-latest
    needs: generate-matrix
    strategy:
      matrix: ${{fromJson(needs.generate-matrix.outputs.matrix)}}
      fail-fast: false
    steps:
      - uses: TobKed/github-forks-sync-action@master
        with:
          github_token: ${{ secrets.GH_PERSONAL_ACCESS_TOKEN }}
          upstream_repository: apache/airflow
          target_repository: TobKed/airflow
          upstream_branch: ${{ matrix.branch }}
          target_branch: ${{ matrix.branch }}
          force: true
          tags: true

License

The Dockerfile and associated scripts and documentation in this project are released under the MIT License.

No affiliation with GitHub Inc.

GitHub are registered trademarks of GitHub, Inc. GitHub name used in this project are for identification purposes only. The project is not associated in any way with GitHub Inc. and is not an official solution of GitHub Inc. It was made available in order to facilitate the use of the site GitHub.