Bolt CMS HTML to AMP HTML Filter ⚡

This Bolt CMS extension converts blocks of regular HTML to AMP compliant HTML using a Twig filter.

Installation Steps 💽

This extension can be installed via the Bolt CMS "Extend" menu in the admin control panel. Search for jamesives/bolt-cms-amp-filter to install.

---

You need to install the Lullabot AMP PHP library in your Bolt CMS root in order for this extension to work correctly. This can be achieved by running the following Composer command inside the root of your Bolt project.

$ composer require lullabot/amp:"^1.0.0"

Getting Started ✈️

In your Twig templates all you need to do is add the amp filter to the HTML you'd like to convert, for example {{ record.body|amp }}. If the filter finds any form of rich media content such as a YouTube embed or image it will automatically convert it to the AMP equivalent.

<div>
  <img alt="This is an image" src="/files/1461.png">
</div>

Will become the following:

<div>
  <amp-img alt="This is an image" src="/files/1461.png" width="567" height="500" layout="responsive"></amp-img>
</div>

If you'd like to return the converted AMP HTML as plain text you can do so by using the ampraw filter, for example {{ record.body|ampraw }}. This is useful if you want to check if the content contains a certain type of AMP component so you can systematically place the JavaScript for it in the page header.

{% set body = record.body|ampraw %}
{% if 'amp-youtube' in body %}
  <script async custom-element="amp-youtube" src="https://cdn.ampproject.org/v0/amp-youtube-0.1.js"></script>   
{% endif %}

Issues with Images

The built in PHP server configuration that is packaged with Bolt CMS may prevent this extension from working properly when it encounters images due to how it handles requests. If you encounter these issues I'd suggest using the Bolt CMS Docker container instead, with this you can setup an extra_hosts field in the docker-compose.yml file and map the Docker container to the host machine, which will allow the PHP to access the images properly.

extra_hosts:
  - "example.com:127.0.0.1"

Special thanks to Christian for the help debugging this issue!

Configuration 📁

Inside the generated configuration file you'll find some options which can be used to customize this extension.

Option	Description	Type
show_action_log	Prints on the page what the AMP library converted and why.	boolean (Defaults to false)