docs: add GitHub Actions to pages documentation

fixes #165 

Co-Authored-By: dieghernan@users.noreply.github.com

Author: Haroenv

docs-src/src/github-pages.md

@@ -5,20 +5,56 @@ layout: content-with-menu.pug
 
 # Deploying on GitHub Pages
 
-GitHub offers free hosting for static websites through its [GitHub Pages][1] feature.
-It also has builtin support for Jekyll website. Once [properly configured][2],
-every time you push your Jekyll website to GitHub, it will be deployed on
-a `username.github.io/reponame` url.
+GitHub offers free hosting for static websites through its [GitHub Pages][1] feature. It also has builtin support for Jekyll website. Once [properly configured][2], every time you push your Jekyll website to GitHub, it will be deployed on a `username.github.io/reponame` url.
 
-But GitHub will only build your website (`jekyll build`), it will not run other
-commands (like `jekyll algolia`), so if you want to update your search results on
-each push, you'll have to find another way.
+But GitHub will only build your website (`jekyll build`), it will not run other commands (like `jekyll algolia`), so if you want to update your search results on each push, you'll have to find another way. This can be done using GitHub Actions, or via a Continuous Integration provider like Travis CI.
 
-We recommend using [Netlify][3], but if you want to stay hosted on GitHub pages,
-this page will explain how to keep your search records in sync with your
-deployed website.
+We recommend using [Netlify][3] to host the whole pipeline, but if you want to stay hosted on GitHub pages, this page will explain how to keep your search records in sync with your deployed website.
 
-## Enabling Travis
+## Using GitHub Actions
+
+First enable [GitHub Actions][6] on your account, and then create this new action under for example `.github/workflows/algolia-search.yml`.
+
+```yaml
+on:
+  push:
+    branches:
+      - master
+      - main
+
+name: algolia-search
+
+jobs:
+  algolia-search:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-ruby@v1
+        with:
+          ruby-version: '2.6'
+      - uses: actions/cache@v2
+        with:
+          path: vendor/bundle
+          key: ${{ runner.os }}-gems-${{ hashFiles('**/Gemfile.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-gems-
+
+      - name: Bundle install
+        run: |
+          bundle config path vendor/bundle
+          bundle install --jobs 4 --retry 3
+
+      - name: Exec jekyll algolia
+        run: bundle exec jekyll algolia
+        env:
+          ALGOLIA_API_KEY: ${{ secrets.ALGOLIA_API_KEY }}
+```
+
+Then create `ALGOLIA_API_KEY` secret in the repository settings > secrets with the Admin API Key.
+
+## Using Travis CI
+
+### Enabling Travis
 
 [Travis CI][4] is an hosted continuous integration service, and it's free for
 open-source projects. It can listen to any changes in your GitHub repository and
@@ -38,7 +74,7 @@ This will avoid re-indexing your data every time you receive a pull request._
 
 ![Travis configuration](./assets/images/travis-config.png)
 
-## Configuring Travis
+### Configuring Travis
 
 Now that Travis is enabled, we have to configure it to tell it what to do on
 every new push to your repo. This can be done through the Travis UI, but we
@@ -59,18 +95,17 @@ branches:
     # Change this to gh-pages if you're deploying using the gh-pages branch
     - master
 rvm:
- - 2.4
+  - 2.4
 ```
 
 This file will be read by Travis and instruct it to fetch all the dependencies
-defined in the `Gemfile` through Bundler. It will then run `bundle exec jekyll
-algolia` which will actually index your data.
+defined in the `Gemfile` through Bundler. It will then run `bundle exec jekyll algolia` which will actually index your data.
 
 You might have to edit the `branches.only` value to either `master` or
 `gh-pages`, depending on which branch is configured to be deployed in your
 GitHub Pages configuration.
 
-### Ignoring vendors
+#### Ignoring vendors
 
 Travis bundles all gems in the `vendor` directory on its servers, which Jekyll
 will mistakenly read. This will likely make the process fail. To avoid this,
@@ -80,7 +115,7 @@ add `vendor` to the `exclude` list in your `_config.yml` file.
 exclude: [vendor]
 ```
 
-## Adding the API Key
+### Adding the API Key
 
 The plugin will need your Admin API key to push data. Because you don't want to
 expose this key in your repository, you'll have to add `ALGOLIA_API_KEY` as an
@@ -89,7 +124,7 @@ Settings page.
 
 ![Travis environment variables](./assets/images/travis-env.png)
 
-## Done
+### Done
 
 Commit all the changes you made, and then push your repository. Travis will
 catch the event and trigger your indexing for you. You can follow the Travis job
@@ -100,3 +135,4 @@ execution directly on your Travis dashboard, with a full log.
 [3]: ./netlify.html
 [4]: https://travis-ci.org/
 [5]: https://travis-ci.org/
+[6]: https://github.com/features/actions