README

A ProcessWire module adding Twig to the TemplateEngineFactory.

Requirements

• ProcessWire 3.0 or newer
• TemplateEngineFactory 2.0 or newer
• PHP >= 7.0 for version 2.x, PHP >= 7.2.5 for version 3.x
• Composer

The 1.x version of this module is available on the 1.x branch. Use this version if you still use TemplateEngineFactory 1.x.

Installation

Execute the following command in the root directory of your ProcessWire installation:

composer require wanze/template-engine-twig:^3.0

This will install the TemplateEngineTwig and TemplateEngineFactory modules in one step. Afterwards, don't forget to enable Twig as engine in the TemplateEngineFactory module's configuration.

ℹ️ This module includes test dependencies. If you are installing on production with composer install, make sure to pass the --no-dev flag to omit autoloading any unnecessary test dependencies!.

Configuration

The module offers the following configuration:

• Template files suffix The suffix of the Twig template files, defaults to twig.html.
• Provide ProcessWire API variables in Twig templates API variables ($pages, $input, $config...) are accessible in Twig, e.g. {{ config }} for the config API variable.
• Debug If enabled, Twig outputs debug information. The module also registers the Debug Extension, offering the {{ dump() }} function to inspect variables.
• Auto reload templates (recompile) If enabled, templates are recompiled whenever the source code changes.
• Strict variables If set to false, Twig will silently ignore invalid variables (variables and or attributes/methods that do not exist) and replace them with a null value. When set to true, Twig throws an exception instead
• Auto escape variables If enabled, templates will auto-escape variables. If you are using ProcessWire textformatters to escape field values, do not enable this feature.

Extending Twig

It is possible to extend Twig after it has been initialized by the module. Hook the method TemplateEngineTwig::initTwig to register custom functions, extensions, global variables, filters etc.

Here is an example how you can use the provided hook to attach a custom function.

wire()->addHookAfter('TemplateEngineTwig::initTwig', function (HookEvent $event) {
    /** @var \Twig\Environment $twig */
    $twig = $event->arguments('twig');

    $twig->addFunction(new \Twig\TwigFunction('processwire', function () {
        return 'ProcessWire rocks!';
    }));
});

// ... and then use it anywhere in a Twig template:

{{ processwire() }}

The above hook can be put in your site/init.php file. If you prefer to use modules, put it into the module's init() method and make sure that the module is auto loaded.

Use Twig Extensions

The Twig Extensions is a library that provides several useful extensions for Twig.

These extensions are not included in the module by default, but you can add them to Twig using the same hook explained above.

Fist, install the library with Composer in the ProcessWire root directory: composer require twig/extensions. Next, use the same hook as above to register the desired extensions.

wire()->addHookAfter('TemplateEngineTwig::initTwig', function (HookEvent $event) {
    /** @var \Twig\Environment $twig */
    $twig = $event->arguments('twig');
    
    // Register the extensions.
    $twig->addExtension(new Twig_Extensions_Extension_Text());
    $twig->addExtension(new Twig_Extensions_Extension_I18n());
    $twig->addExtension(new Twig_Extensions_Extension_Intl());
});