Simple workflow file for Github Actions to deploy your WordPress theme

main.yml

# This is a basic workflow to help you get started with Actions
# The name of the script you are intending to run.

name: Deployment

# Controls when the workflow will run
on:
  # Triggers the workflow on push or pull request events but only for the main branch. 
  # I left my branch name as main, but you could change this to whatever your branches are called.
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

  # Allows you to run this workflow manually from the Actions tab
  workflow_dispatch:

# A workflow run is made up of one or more jobs that can run sequentially or in parallel
jobs:
  # This workflow contains a single job called "build"
  build:
    # The type of runner that the job will run on
    # I think this is related to the server you are "borrowing" from Github to run the actions on.
    runs-on: ubuntu-latest

    # Steps represent a sequence of tasks that will be executed as part of the job
    steps:
      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
      # I'm not sure why you need this other than to suggest that you are using a GH server to run these scripts,
      # so you likely need to run a little checkout of the repo so you have files locally before sending them
      # to your server.
      - uses: actions/checkout@v2

      # Runs a set of commands using the runners shell
      - name: Sync
        env:
          dest: 'ssh-user@server-ip-or-domain:/file/location/to/wp-content/themes/your-theme-name/'          
          # The run below is what you would run if you were using rsync between your local computer and server.
          # The fist 2 lines are necessary to pull the deploy key out of the secret so you can connect to the server.
          # I chose to exclude the deploy_key, .git and .github folders as they are not necessary for the theme to run on the 
          # server. If you wanted to include those you could.
        run: |
          echo "${{secrets.DEPLOY_KEY}}" > deploy_key
          chmod 600 ./deploy_key
          rsync -chav --delete \
            -e 'ssh -i ./deploy_key -o StrictHostKeyChecking=no' \
            --exclude /deploy_key \
            --exclude /.git/ \
            --exclude /.github/ \
            ./ ${{env.dest}}