kingkool68 / sprig

Bare bones Twig templating support for WordPress

Sprig

Bare bones Twig templating support for WordPress

Sprig brings the Twig templating engine to WordPress. Install the plugin and get started separating your HTML from PHP.

Other Twig plugins like Timber try to bring lots of WordPress functionality into Twig. Sprig believes in separating PHP from HTML as much as possible. PHP is for gathering and massaging data and Sprig/Twig templates are for rendering HTML using the data passed to it. Keep things simple and only pass data to a template that the template needs to render.

Installation

1. Clone this repo or download a zip
2. Add this to the plugin directory of your WordPress site in /wp-content/plugins/
3. Run composer install to download the Twig template engine dependency

How to Use

Create a directroy in your theme called views or twig to hold your Twig template files. Render your templates using the following methods passing an array of data to be used by the template.

• Sprig::render() will render a Twig template using an array of data and return it as a string
• Sprig::out() will echo a rendered template
• Sprig::do_action() will capture the output of a WordPress action and return a string

Example

example.php

<?php
$context = array(
  'title' => 'Sprig is awesome!',
  'url'   => 'https://github.com/kingkool68/sprig/',
);

// Render the template and return a string
$thing = Sprig::render( 'example.twig', $context );

// Echo out the rendered template
Sprig::out( 'example.twig', $context );

example.twig

<p>
	<a href="{{ url|esc_url }}">{{ title }}</a>
</p>

Output

<p>
	<a href="https://github.com/kingkool68/sprig/">Sprig is awesome!</a>
</p>

Demo Theme

I've put together a simple demo theme to show how Sprig can be used within a WordPress theme.

Twig Filters

Twig filters allow a string to be manipulated in a Twig template. Most of the default filters in Sprig are WordPress' escaping functions for securing output as late as possible.

• esc_attr
• esc_html
• esc_url
• esc_js
• esc_textarea
• tag_escape
• sanitize_email
• sanitize_html_class
• antispambot
• wptexturize
• absint

Additional Twig filters can be added via the WordPress filter sprig/twig/filters and adding a callable function with a key to the array. This filter should be called before the init action so Twig filters can be set up properly in time.

Example for adding the sanitize_title() function as a Twig filter:

function filter_sprig_twig_filters( $filters = array() ) {
	$filters['sanitize_title'] = 'sanitize_title';
	return $filters;
}
add_filter( 'sprig/twig/filters', 'filter_sprig_twig_filters' );

Twig Functions

Twig functions let you call PHP functions from within Twig templates. Sprig enables a handful of WordPress functions used in the base Twig template and WordPress' checked/selected/disabled form helpers.

• checked()
• selected()
• disabled()
• wp_head()
• wp_footer()
• body_class()
• get_header()
• get_footer()
• wp_title()

Additional Twig functions can be added via the WordPress filter sprig/twig/functions and adding a callable function with a key to the array. This filter should be called before the init action so Twig functions can be set up properly in time.

Example for adding the wp_nonce_field() function as a Twig function:

function filter_sprig_twig_functions( $functions = array() ) {
	$functions['wp_nonce_field'] = 'wp_nonce_field';
	return $functions;
}
add_filter( 'sprig/twig/functions', 'filter_sprig_twig_functions' );

Extending Sprig

Sprig offers various WordPress filters to customize its behavior.

• sprig/twig for modifying Twig itself
• sprig/twig/filters for adding or removing available Twig filters
• sprig/twig/functions for adding or removing available Twig functions
• sprig/roots for modifying which directories Twig should look for twig templates in
• sprig/theme_dirs for modifying the name of directories to look for Twig templates in (Example: if you want to change the directory from views or twig to templates)
• sprig/twig_loader for modifying the Twig loader environment (see https://twig.symfony.com/doc/2.x/api.html)

PHP Compatibility

PHP compatibility is dependent on Twig's PHP prerequisites. Use the appropriate branch of Sprig to meet your minimum PHP requirements.

• Twig 3.x needs at least PHP 7.2.0 to run, use the Sprig master branch.
• Twig 2.x needs at least PHP 7.0.0 to run, use the Sprig 2.x branch.
• Twig 1.x needs at least PHP 5.5.0 to run , use the Sprig 1.x branch.