Eleventy + Twig.js

This package adds a .twig template engine to Eleventy that lets you use the pure JavaScript implementation of the Twig PHP templating language called Twig.js.

Features

• Built-in Shortcodes: Uses twig.extendFunction() to extend Twig
• Twig Namespaces: Uses Twig built-in loaders to provide namespaces
• Responsive Images: Uses @11ty/eleventy-img plugin to autogenerate responsive images
• Hashed Assets: If you have generated a manifest (e.g. with @factorial/eleventy-plugin-fstack) you could let Eleventy replace unhashed assets like css/js automatically with their hashed versions

Getting Started

Install the latest @factorial/eleventy-plugin-twig release as well as twig and optionally @11ty/eleventy-img as node modules with yarn:

yarn add --dev @factorial/eleventy-plugin-twig @11ty/eleventy-img twig

or npm:

npm install --save-dev @factorial/eleventy-plugin-twig @11ty/eleventy-img twig

Usage

For Eleventy to recognize this you have to register this as a plugin. To do so modify the .eleventy.js config file:

const eleventyPluginTwig = require("@factorial/eleventy-plugin-twig");

module.exports = function(eleventyConfig) {
  ...
  eleventyConfig.addPlugin(eleventyPluginTwig, USER_OPTIONS);
  ...
}

As mentioned in the eleventyConfig.addPlugin(eleventy-plugin-twig, USER_OPTIONS) some options can be defined optionally. Currently @factorial/eleventy-plugin-twig provides the following configuration object:

/**
 * @typedef {object} ELEVENTY_DIRECTORIES
 * @property {string} input - Eleventy template path
 * @property {string} output - Eleventy build path
 * @property {string} [includes] - Eleventy includes path relativ to input
 * @property {string} [layouts] - Eleventy separate layouts path relative to input
 * @property {string} [watch] - add more watchTargets to Eleventy
 */

/**
 * @typedef {object} ASSETS
 * @property {string} root - path to the root folder from projects root (e.g. src)
 * @property {string} base - base path for assets relative to the root folder (e.g. assets)
 * @property {string} css - path to the css folder relative to the base (e.g. css)
 * @property {string} js - path to the js folder relative to the base (e.g. js)
 * @property {string} images - path to the image folder relative to the base (e.g. images)
 */

/**
 * @typedef {object} IMAGES
 * @property {Array<number>} widths - those image sizes will be autogenereated / aspect-ratio will be respected
 * @property {Array<import("@11ty/eleventy-img").ImageFormatWithAliases>} formats - jpeg/avif/webp/png/gif
 * @property {string} additionalAttributes - those attributes will be added to the image element
 */

/**
 * @typedef {object} SHORTCODE
 * @property {string} symbol - method name for twig to register
 * @property {function(import("@11ty/eleventy").UserConfig, USER_OPTIONS, ...* ):any} callback - callback which is called by twig
 */

/**
 * @typedef {object} TWIG_OPTIONS
 * @property {SHORTCODE[]} [shortcodes] - array of shortcodes
 * @property {boolean} [cache] - you could enable the twig cache for whatever reasons here
 * @property {Object<string, string>} [namespaces] - define namespaces to include/extend templates more easily by "@name"
 */

/**
 * @typedef {object} USER_OPTIONS
 * @property {string} [mixManifest] - path to the mixManifest file relative to the build folder
 * @property {ASSETS} [assets] - where to find all the assets relative to the build folder
 * @property {IMAGES} [images] - options for Eleventys image processing
 * @property {ELEVENTY_DIRECTORIES} dir - Eleventy folder decisions
 * @property {TWIG_OPTIONS} [twig] - twig options
 */

You could use this as a starting point and customize to your individual needs:

/**
 * @type {USER_OPTIONS} USER_OPTIONS
 */
const USER_OPTIONS = {
  twig: {
    namespaces: {
      elements: "src/include/elements",
      patterns: "src/include/patterns",
      "template-components": "src/include/template-components",
      templates: "src/include/templates",
    },
  },
  mixManifest: "mix-manifest.json",
  assets: {
    root: "src",
    base: "assets",
    css: "css",
    js: "js",
    images: "images",
  },
  images: {
    widths: [300, 600, 900],
    formats: ["webp", "avif", "jpeg"],
    additionalAttributes: "",
  },
  dir: {
    output: "build",
    src: "src",
    input: "src/include/templates",
    layouts: "src/layouts",
    watch: "src/**/*.{css,js,twig}",
  },
};

Shortcodes

mix

If you've generated a mixManifest and add the path to it to the USER_OPTIONS then it's possible to add the non hashed files to a template e.g.:

{{ mix("/path/to/unhashed/asset.css") }} --> will result in /path/to/hashed/asset.hash-1234.css

Please provide a path relative so that userOptions.assets.root + userOptions.base + providedPath reaches the asset from your projects root.

asset_path

This is a simple helper shortcode to make your defined asset path userOptions.assets.base available in a template:

{{ asset_path() }} --> will result in /userOptions.assets.base like "/assets"

image

This uses @11ty/eleventy-img to generate responsive images in defined formats (userOptions.images.formats) and sizes (userOptions.images.widths). You could also provide certain additionalAttributes via config for lazyloading etc.

{{ image("src", "alt", "classes") }} --> will result in a proper <picture> element with different <source> elements for each format and defined widths

• src: this has to be relative to the userOptions.assets.images folder
• alt: mandatory! ("" is possible)
• optional classes: Array<string>

To be done

• Proper caching
• Make features optional
• ...

Acknowledgements

This Eleventy + Twig.js plugin uses open source software and would not have been possible without the excellent work of the Eslint, Eleventy, Prettier, debug and Twig.js teams! Thanks a lot!

Sponsored by