Twig for Developers ¶

Compilation Cache ¶

All template loaders can cache the compiled templates on the filesystem for future reuse. It speeds up Twig a lot as templates are only compiled once.

Built-in Loaders ¶

Here is a list of the built-in loaders:

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$loader = new \Twig\Loader\FilesystemLoader($templateDir);

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$loader = new \Twig\Loader\FilesystemLoader([$templateDir1, $templateDir2]);

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$loader->addPath($templateDir3);
$loader->prependPath($templateDir4);

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$loader->addPath($templateDir, 'admin');

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$twig->render('@admin/index.html', []);

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$loader = new \Twig\Loader\FilesystemLoader('templates', getcwd().'/..');

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$loader = new \Twig\Loader\ArrayLoader([
    'index.html' => 'Hello {{ name }}!',
]);
$twig = new \Twig\Environment($loader);

echo $twig->render('index.html', ['name' => 'Fabien']);

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$loader1 = new \Twig\Loader\ArrayLoader([
    'base.html' => '{% block content %}{% endblock %}',
]);
$loader2 = new \Twig\Loader\ArrayLoader([
    'index.html' => '{% extends "base.html" %}{% block content %}Hello {{ name }}{% endblock %}',
    'base.html'  => 'Will never be loaded',
]);

$loader = new \Twig\Loader\ChainLoader([$loader1, $loader2]);

$twig = new \Twig\Environment($loader);

Create your own Loader ¶

All loaders implement the \Twig\Loader\LoaderInterface:

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interface \Twig\Loader\LoaderInterface
{
    /**
     * Returns the source context for a given template logical name.
     *
     * @param string $name The template logical name
     *
     * @return \Twig\Source
     *
     * @throws \Twig\Error\LoaderError When $name is not found
     */
    public function getSourceContext($name);

    /**
     * Gets the cache key to use for the cache for a given template name.
     *
     * @param string $name The name of the template to load
     *
     * @return string The cache key
     *
     * @throws \Twig\Error\LoaderError When $name is not found
     */
    public function getCacheKey($name);

    /**
     * Returns true if the template is still fresh.
     *
     * @param string    $name The template name
     * @param timestamp $time The last modification time of the cached template
     *
     * @return bool    true if the template is fresh, false otherwise
     *
     * @throws \Twig\Error\LoaderError When $name is not found
     */
    public function isFresh($name, $time);

    /**
     * Check if we have the source code of a template, given its name.
     *
     * @param string $name The name of the template to check if we can load
     *
     * @return bool    If the template source code is handled by this loader or not
     */
    public function exists($name);
}

The isFresh() method must return true if the current cached template is still fresh, given the last modification time, or false otherwise.

The getSourceContext() method must return an instance of \Twig\Source.

Core Extension ¶

The core extension defines all the core features of Twig:

• Tags;
  タグ;
• Filters;
  フィルター;
• Functions;
  機能;
• Tests.
  テスト。

Escaper Extension ¶

The escaper extension adds automatic output escaping to Twig. It defines a tag, autoescape, and a filter, raw.

When creating the escaper extension, you can switch on or off the global output escaping strategy:

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$escaper = new \Twig\Extension\EscaperExtension('html');
$twig->addExtension($escaper);

If set to html, all variables in templates are escaped (using the html escaping strategy), except those using the raw filter:

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{{ article.to_html|raw }}

You can also change the escaping mode locally by using the autoescape tag:

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{% autoescape 'html' %}
    {{ var }}
    {{ var|raw }}      {# var won't be escaped #}
    {{ var|escape }}   {# var won't be double-escaped #}
{% endautoescape %}

The escaping rules are implemented as follows:

• Literals (integers, booleans, arrays, ...) used in the template directly as variables or filter arguments are never automatically escaped:

  テンプレートで変数またはフィルター引数として直接使用されるリテラル (整数、ブール値、配列など) は、自動的にエスケープされることはありません。

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  {{ "Twig<br/>" }} {# won't be escaped #} {% set text = "Twig<br/>" %} {{ text }} {# will be escaped #}

• Expressions which the result is a literal or a variable marked safe are never automatically escaped:

  結果がリテラルまたは safe とマークされた変数である式は、自動的にエスケープされることはありません。

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  {{ foo ? "Twig<br/>" : "<br/>Twig" }} {# won't be escaped #} {% set text = "Twig<br/>" %} {{ true ? text : "<br/>Twig" }} {# will be escaped #} {{ false ? text : "<br/>Twig" }} {# won't be escaped #} {% set text = "Twig<br/>" %} {{ foo ? text|raw : "<br/>Twig" }} {# won't be escaped #}

• Objects with a __toString method are converted to strings and escaped. You can mark some classes and/or interfaces as being safe for some strategies via EscaperExtension::addSafeClass():

  __toString メソッドを持つオブジェクトは文字列に変換され、エスケープされます。 EscaperExtension::addSafeClass() を使用して、いくつかのクラスやインターフェースをいくつかの戦略に対して安全であるとマークすることができます。

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  // mark object of class Foo as safe for the HTML strategy $escaper->addSafeClass('Foo', ['html']); // mark object of interface Foo as safe for the HTML strategy $escaper->addSafeClass('FooInterface', ['html']); // mark object of class Foo as safe for the HTML and JS strategies $escaper->addSafeClass('Foo', ['html', 'js']); // mark object of class Foo as safe for all strategies $escaper->addSafeClass('Foo', ['all']);

• Escaping is applied before printing, after any other filter is applied:

  他のフィルタが適用された後、印刷前にエスケープが適用されます。

  1	{{ var|upper }} {# is equivalent to {{ var|upper|escape }} #}

• The `raw` filter should only be used at the end of the filter chain:

  `raw` フィルターは、フィルター チェーンの最後でのみ使用する必要があります。

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  {{ var|raw|upper }} {# will be escaped #} {{ var|upper|raw }} {# won't be escaped #}

• Automatic escaping is not applied if the last filter in the chain is marked safe for the current context (e.g. html or js). escape and escape('html') are marked safe for HTML, escape('js') is marked safe for JavaScript, raw is marked safe for everything.

  チェーンの最後のフィルターが現在のコンテキスト (html や js など) に対して安全であるとマークされている場合、自動エスケープは適用されません。 escape および escape('html') は HTML に対して安全であるとマークされ、escape('js') は JavaScript に対して安全であるとマークされ、raw はすべてに対して安全であるとマークされています。

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  {% autoescape 'js' %} {{ var|escape('html') }} {# will be escaped for HTML and JavaScript #} {{ var }} {# will be escaped for JavaScript #} {{ var|escape('js') }} {# won't be double-escaped #} {% endautoescape %}

Sandbox Extension ¶

The sandbox extension can be used to evaluate untrusted code. Access to unsafe attributes and methods is prohibited. The sandbox security is managed by a policy instance. By default, Twig comes with one policy class: \Twig\Sandbox\SecurityPolicy. This class allows you to white-list some tags, filters, properties, and methods:

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$tags = ['if'];
$filters = ['upper'];
$methods = [
    'Article' => ['getTitle', 'getBody'],
];
$properties = [
    'Article' => ['title', 'body'],
];
$functions = ['range'];
$policy = new \Twig\Sandbox\SecurityPolicy($tags, $filters, $methods, $properties, $functions);

With the previous configuration, the security policy will only allow usage of the if tag, and the upper filter. Moreover, the templates will only be able to call the getTitle() and getBody() methods on Article objects, and the title and body public properties. Everything else won't be allowed and will generate a \Twig\Sandbox\SecurityError exception.

The policy object is the first argument of the sandbox constructor:

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$sandbox = new \Twig\Extension\SandboxExtension($policy);
$twig->addExtension($sandbox);

By default, the sandbox mode is disabled and should be enabled when including untrusted template code by using the sandbox tag:

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{% sandbox %}
    {% include 'user.html' %}
{% endsandbox %}

You can sandbox all templates by passing true as the second argument of the extension constructor:

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$sandbox = new \Twig\Extension\SandboxExtension($policy, true);

Profiler Extension ¶

The profiler extension enables a profiler for Twig templates; it should only be used on your development machines as it adds some overhead:

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$profile = new \Twig\Profiler\Profile();
$twig->addExtension(new \Twig\Extension\ProfilerExtension($profile));

$dumper = new \Twig\Profiler\Dumper\TextDumper();
echo $dumper->dump($profile);

A profile contains information about time and memory consumption for template, block, and macro executions.

You can also dump the data in a Blackfire.io compatible format:

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$dumper = new \Twig\Profiler\Dumper\BlackfireDumper();
file_put_contents('/path/to/profile.prof', $dumper->dump($profile));

Upload the profile to visualize it (create a free account first):

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blackfire --slot=7 upload /path/to/profile.prof

Optimizer Extension ¶

The optimizer extension optimizes the node tree before compilation:

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$twig->addExtension(new \Twig\Extension\OptimizerExtension());

By default, all optimizations are turned on. You can select the ones you want to enable by passing them to the constructor:

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$optimizer = new \Twig\Extension\OptimizerExtension(\Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_FOR);

$twig->addExtension($optimizer);

Twig supports the following optimizations:

• \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_ALL, enables all optimizations (this is the default value).
  \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_ALL、すべての最適化を有効にします (これはデフォルト値です)。
• \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_NONE, disables all optimizations. This reduces the compilation time, but it can increase the execution time and the consumed memory.
  \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_NONE は、すべての最適化を無効にします。これにより、コンパイル時間が短縮されますが、実行時間と消費メモリが増加する可能性があります。
• \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_FOR, optimizes the for tag by removing the loop variable creation whenever possible.
  \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_FOR は、可能な限りループ変数の作成を削除して for タグを最適化します。
• \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_RAW_FILTER, removes the raw filter whenever possible.
  \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_RAW_FILTER は、可能な限り rawfilter を削除します。
• \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_VAR_ACCESS, simplifies the creation and access of variables in the compiled templates whenever possible.
  \Twig\NodeVisitor\OptimizerNodeVisitor::OPTIMIZE_VAR_ACCESS は、コンパイルされたテンプレートでの変数の作成とアクセスを可能な限り簡素化します。