Magento2 itself uses PHP as the template engine (as what PHP has been developed for in ~1996 ;-) ).

The Twig template engine cannot execute directly PHP code which seems more secure.

This module is meant to be used additionally to the .phtml files and does not provide any .twig template file.

The biggest advantage of using Twig templates instead of .phtml PHP native files is that you cannot really add a lot of business logic and not even add database queries into the template.

Twig forces you to move you business logic into a model.

A use case for this Magento2 module would be if you write your first Magento2 module you can require this package and write all your template files in Twig.

Latest commit and statistics from GitHub:

Tweets

Magento2 modularity: @SchumacherFM replaced the templating engine with only a few config files and 150 lines of code https://t.co/Xz5VfYSXXa

— Fooman (@foomanNZ) January 18, 2015

@SchumacherFM @akent99 perfect example of when Magento should not build and let an extension/module be built from the community

— Paul Boisvert (@ProductPaul) January 18, 2015

Events & Configuration

The Twig template engine class dispatches two events so that you can modify Twig.

Event twig_loader with event object loader. You can set loader any other class which implements Twig_LoaderInterface. http://twig.sensiolabs.org/doc/api.html#loaders

Event twig_init with event object twig. You can add here more functions, filters, tags, etc. http://twig.sensiolabs.org/doc/advanced.html

Configuration options can be found Stores -> Settings -> Configuration -> Advanced -> Developer -> Twig.

Frontend Integration

Your template files must have the file extension .twig to get automatically recognized.

In your layout xml files or blocks please specify the new template

<referenceBlock name="top.links">
    <block class="Magento\Theme\Block\Html\Header" template="html/header.twig" name="header" as="header" before="-">
        <arguments>
            <argument name="show_part" xsi:type="string">welcome</argument>
        </arguments>
    </block>
</referenceBlock>

Example header.phtml converted to header.twig

<?php switch ($this->getShowPart()):
    case 'welcome': ?>
        <li class="greet welcome"><?php echo $this->getWelcome() ?></li>
    <?php break; ?>
    <?php case 'other': ?>
        <?php echo $this->getChildHtml(); ?>
    <?php break; ?>
<?php endswitch; ?>

{% if getShowPart() == 'welcome' %}
    <li class="greet welcome">{{ getWelcome() }}</li>
{% endif %}

{% if getShowPart() == 'other' %}
    {{ getChildHtml() }}
{% endif %}

Example breadcrumbs.phtml converted to breadcrumbs.twig

<?php if ($crumbs && is_array($crumbs)) : ?>
<div class="breadcrumbs">
    <ul class="items">
        <?php foreach ($crumbs as $crumbName => $crumbInfo) : ?>
            <li class="item <?php echo $crumbName ?>">
            <?php if ($crumbInfo['link']) : ?>
                <a href="<?php echo $crumbInfo['link'] ?>" title="<?php echo $this->escapeHtml($crumbInfo['title']) ?>">
                    <?php echo $this->escapeHtml($crumbInfo['label']) ?>
                </a>
            <?php elseif ($crumbInfo['last']) : ?>
                <strong><?php echo $this->escapeHtml($crumbInfo['label']) ?></strong>
            <?php else: ?>
                <?php echo $this->escapeHtml($crumbInfo['label']) ?>
            <?php endif; ?>
            </li>
        <?php endforeach; ?>
    </ul>
</div>
<?php endif; ?>

{% if crumbs %}
<div class="breadcrumbs">
    <ul class="items">
    {% for crumbName,crumbInfo in crumbs %}
        <li class="item {{ crumbName }}">
            {% if crumbInfo.link %}
                <a href="{{ crumbInfo.link }}" title="{{ crumbInfo.title }}">
                    {{ crumbInfo.label }}
                </a>
            {% elseif crumbInfo.last %}
                <strong>{{ crumbInfo.label }}</strong>
            {% else %}
                {{ crumbInfo.label }}
            {% endif %}
        </li>
    {% endfor %}
    </ul>
</div>
{% endif %}

Access helper methods

Write in your .twig file:

{{ helper("Magento\\Core\\Helper\\Url").getHomeUrl() }}

Installation via Composer

Add the following to the require section of your Magento 2 composer.json file

"schumacherfm/mage2-twig": "dev-master"

additionally add the following in the repository section

    "repositories": [
    {
        "type": "vcs",
        "url": "https://github.com/SchumacherFM/Magento2-Twig.git"
    }
]

run composer update

add the following to app/etc/config.php

'SchumacherFM_Twig'=>1