How to: Deploy GitHub Pages on a Schedule to Publish Future Posts

I have a Jekyll-based blog that is deployed via GitHub Pages. Because Jekyll is a static site generator, you can't release future posts unless you trigger a build (normally by making a commit).

However, today we're going to fix that. With any luck, this is the first post that I scheduled and published in advance!

Solution

We're going to use GitHub Actions and a little bit of curl to accomplish what we need.

Step 1: Create an Access Token

• Head to https://github.com/settings/tokens.
• Click the button to create a new token
• Give it a name, such as "GitHub Pages Automated Build" or something similar.
• Copy the access token somewhere temporarily, since you'll lose it after you navigate away.

Step 2: Create a Secret for Your Access Token

• Open the repository that holds your GitHub pages site
• Navigate to Settings --> Secrets
• Create a new secret, named PAGES_ACCESS_TOKEN and paste in your personal access token that you created.

Step 3: Update Your Jekyll Configuration

You'll need to disable the publishing of future posts.

In your _config.yml file, add:

future: false

Step 4: Create a GitHub action

In your repository, create a file at /github/workflows/scheduled-posts.yml.

Drop the following lines into it:

name: Build every hour

on:
  schedule:
   - cron: '0 * * * *'
jobs:
  curl:
    runs-on: ubuntu-latest
    steps:
    - name: curl
      uses: wei/curl@master
      with:
        args: "-X POST -H 'Authorization: token ${{ secrets.PAGES_ACCESS_TOKEN }}' -H 'Accept: application/vnd.github.ant-man-preview+json' https://api.github.com/repos/YourUserName/YourRepository/pages/builds"

Let's break this down line by line:

• First, we give the workflow a name
• Then, we specify that it will run on a cron schedule of every hour, on the hour.
• We then specify what jobs the action will run.
• In this case, we specify a job called curl.
• We create one step underneath this job, which we also call curl.
• We specify that we're using a container, in this case wei/curl, which is a container that installs curl on top of Alpine Linux.

We then specify the curl arguments. I'll break these down.

• -X POST: this will be an HTTP POST request
• -H 'Authorization: token ${{ secrets.PAGES_ACCESS_TOKEN }}': Uses the secret that contains our access token, in order to authenticate.
• -H 'Accept: application/vnd.github.ant-man-preview+json': This is apparently required by the GitHub API in order to allow access
• https://api.github.com/repos/YourUserName/YourRepository/pages/builds: This is the API endpoint of GitHub pages if you want to trigger a pages build. (substituting your username and repository name)

The Result?

You can see the current workflow here in my master branch

I'm excited that GitHub has enabled this kind of functionality; it has a ton of potential to make life easier for those of us using the platform.

Happy publishing!