The GitHub Actions workflow definition for my Gatsby site.

main.yml

# The name of the workflow as it will appear in the Actions tab of the GitHub repository.
name: "Publish my Gatsby site to GitHub Pages."


# Specifies the "event" that automatically triggers the workflow file.
# Here, a push to the dev branch will trigger the jobs below to run.
on:
  push:
    branches:
      - dev

# This workflow is made up of one job.
jobs:
  # The job is called "build"
  build:
    # Configures the runner. This job will run on an Ubuntu Linux virtual machine.
    runs-on: ubuntu-latest
    # Define the steps to perform the "build" job
    # 1. Check out this repository to the runner, now it is possible to run actions against the code
    # 2. Build and deploy the website using the community action
    # Configure the access token to allow pushing the build to the repository
    # Configure the branch that GitHub accepts as source of the static files. 
    steps:
      - uses: actions/checkout@v1
      - uses: enriikke/gatsby-gh-pages-action@v2
        with:
          access-token: ${{ secrets.WEBSITE }}
          deploy-branch: gh-pages