github-action-file-sync

Github Action to sync files across repos

Use Cases

Great for keeping your files in sync across multiple repositories. A good use case for me was the .github/dependabot.yml files.

I have a main repo where these are synced from, and then they are kept in sync with the main repository.

If I need to make a change, rather than go make a change x many times across all my repositories, I make the change once, and on push to the main repository, all my child repositories are updated.

Another example is if you're creating new Github Actions for a repository, you can make them once, check them into main repository, and then deploy them all across all your repositories all at once.

This also isn't limited to Github Action yaml files - another use case could be keeping the .editorconfig, LICENSE, tsconfig.json, eslintrc.yml, .gitignore, azure-pieplines.yml, etc. in sync across all your repositories.

If I have a file that gets out of sync for whatever reason, the cron side of the on will take care of putting it back in sync with the main repository.

See my main sync repo for examples on how I use it across all my repositories.

Setup

Create a new file called /.github/workflows/file-sync.yml that looks like so:

name: File Sync

on:
  push:
    branches:
      - main
  schedule:
    - cron: 0 0 * * *

jobs:
  file_sync:
    runs-on: ubuntu-latest
    steps:
      - name: Fetching Local Repository
        uses: actions/checkout@main
      - name: File Sync
        uses: kbrashears5/[email protected]
        with:
          REPOSITORIES: |
            username/repo@main
          FILES: |
            sync/dependabot.yml=.github/dependabot.yml
          TOKEN: ${{ secrets.ACTIONS }}

Parameters

Parameter	Required	Description
REPOSITORIES	true	List of repositories to sync the files to. Optionally provide branch name
FILES	true	List of files to sync across repositories. See below for details
PULL_REQUEST_BRANCH_NAME	false	Branch name of branch to do pull request into. Default is no pull request opened
GIT_EMAIL	false	Git email to use
GIT_USERNAME	false	Git username to use
TOKEN	true	Personal Access Token with repo scope, and workflow scope if managing Actions-related files

Examples

REPOSITORIES parameter

Push to the main branch

REPOSITORIES: |
    username/repo

Push to the dev branch

REPOSITORIES: |
    username/repo@dev

FILES parameter

File sync

Root file with root destination

FILES: |
    dependabot.yml

Root file with new destination

FILES: |
    dependabot.yml=.github/dependabot.yml

Nested file with same nested file structure destination

FILES: |
    .github/dependabot.yml

Nested file with new destination

FILES: |
    sync/dependabot.yml=.github/dependabot.yml

Folder Sync

Root folder to root directory

FILES: |
    sync

Root folder with new directory

FILES: |
    sync/=newFolderName/

PULL_REQUEST_BRANCH_NAME parameter

Specify branch name to create pull request against

PULL_REQUEST_BRANCH_NAME: main

TOKEN parameter

Use the repository secret named ACTIONS

TOKEN: ${{ secrets.ACTIONS }}

Troubleshooting

Spacing

Spacing around the equal sign is important. For example, this will not work:

FILES: |
  folder/file-sync.yml = folder/test.txt

It passes to the shell file 3 distinct objects

• folder/file-sync.ymll
• =
• folder/test.txt

instead of 1 object

• folder/file-sync.yml = folder/test.txt

and there is nothing I can do in code to make up for that

Slashes

You do not need (nor want) leading / for the file path on either side of the equal sign

The only time you need / trailing is for folder copies. While a file copy will technically still work with a leading /, a folder copy will not