Custom Fields

Timber tries to make it as easy as possible for you to retrieve custom meta data for Post, Term, User and Comment objects. And it works with a range of plugins that make it easier for you to create custom fields, like Advanced Custom Fields. While most of this guide applies to everything you do with custom fields, we have a detailed guide for ACF.

Accessing custom values #

When you have a custom field that’s named my_custom_field, you can access it in 3 different ways:

1. Access it through the meta() method.
2. Access it through the raw_meta() method.
3. Define your own method.
4. Directly access it through the field’s name.

Each of these methods behaves a little differently. Let’s look at each one in more detail.

The meta() method #

This method is the recommended way to access meta values. You’ll get values that are filtered by third-party plugins (e.g. Advanced Custom Fields).

Twig

{{ post.meta('my_custom_field') }}

PHP

$my_custom_field = $post->meta('my_custom_field');

The raw_meta() method #

With this method, values are raw (directly from the wp_meta table in the database) and are not filtered by third-party plugins (e.g. Advanced Custom Fields).

Twig

{{ post.raw_meta('my_custom_field') }}

PHP

$my_custom_field = $post->raw_meta( 'my_custom_field' );

Define your own method #

Sometimes you need to modify a meta value before it is returned. You can do that by extending a Timber object and defining your own method. In the following example, we set a custom price() method to format the price that’s saved in a custom field named price.

PHP

class CustomPost extends Timber\Post
{
    /**
     * Gets formatted price.
     */
    public function price()
    {
        $price = $this->meta('price');

        // Remove decimal digits.
        return number_format($price, 0, '', '');
    }
}

In Twig, you would access it like this:

Twig

{{ post.price }}

You’ll know from looking at the code that you call a defined property or method. Be aware that through this method, you might overwrite a method that already exists on for a Timber\Post object (like date), which is totally fine if you know what you’re doing.

Direct access through custom field name #

If a directly accessed property or method doesn’t exist, Timber will fall back to the equivalent {{ post.meta('post') }} call. This means that you can always write {{ post.price }}, even if you don’t have a method defined.

We don’t recommend to use this method, because you might run into conflicts with existing properties or methods on an object.

For example, when you use a custom field that you name date and try to get its value through {{ post.date }}, it won’t work. That’s because date is a method of the Timber\Post object that returns the date a post was published.

In PHP, you’d access the property through $post->date and call the date method through $post->date(). But in Twig, you can call methods without using parentheses. And methods take precedence over properties. Timber uses a PHP technique called Overloading to get meta values using PHP’s __get magic method on Timber\Post, Timber\Term, Timber\User and Timber\Comment objects. This means that when you use {{ post.date }}, it will ...

• Check if method date exists. If it does, it will return what the method produces.
• Otherwise, it will check if a property date exists. If it does, it will return its value.
• Otherwise, it will hit the __get() method, which handles undefined or inaccessible properties. Timber’s __get() method will look for existing meta and return these.

Now, if you ever run into this problem, you should either use the meta() or raw_meta() method.

Accessing all meta values #

In earlier versions of Timber, you could use the custom property on an object to check which meta values were set on a post, term, user or comment object.

Now, to get the values for all meta values that are set on an object, you can use meta() or raw_meta() without passing a field name.

{{ dump(post.meta()) }}
{{ dump(post.raw_meta()) }}

This is only recommended for development purposes, because it might affect your performance if you always request all values.

Performance #

You might be tempted to set variables for repeated calls to meta() or raw_meta() in Twig to save performance. This is not really necessary. Timber uses get_post_meta() internally, which fetches all meta values for an object from the database when the first value is requested and caches the meta values for later meta requests. The only thing you will be bypassing are a couple of filters, which is unlikely to result in a performance savings.

For example, in most cases it’s totally fine to use meta() in an if statement before using it again to display the value:

{% if book.meta('author') %}
    <h3>Author</h3>
    <span>{{ book.meta('author') }}</span>
{% endif %}

However, you should be careful when you use custom field plugins like Advanced Custom Fields, where a lot of processing can happen in filters (like with repeaters or flexible content fields). Here, you might want to cache the result of the meta function either in PHP or in Twig:

{% set gear_items = post.meta('gear_items') %}

{% if gear_items %}
    <h2>Gear Items</h2>

    {% for gear in gear_items %}
        <h3>{{ gear.brand_name }}</h3>

        {% for gear_feature in gear.features %}
            <li>{{ gear_feature }}</li>
        {% endfor %}
    {% endfor %}
{% endif %}

You might also think that you could load all meta values by not passing a field name and access all required values from there. You shouldn’t do this either, because then a lot of filters might run that you won’t need.

DON’T DO THIS

{% set meta = book.meta() %}

{% if meta.author %}
    <h3>Author</h3>
    <span>{{ meta.author }}</span>
{% endif %}

Site options #

You can get site options through a similar method. Instead of meta(), it’s called option(). Here’s an example to retrieve the admin email address:

{{ site.option('admin_email') }}

For site options, it’s also possible to access it directly through its name:

{{ site.admin_email }}

Please be aware that using this might conflict with existing Timber methods on the Timber\Site object. That’s why the option() method is the preferred way to retrieve site options.

Query by custom field value #

This example that uses a WP_Query array shows the arguments to find all posts where a custom field called color has a value of red.

$args = [
    'posts_per_page' => -1,
    'post_type' => 'post',
    'meta_key' => 'color',
    'meta_value' => 'red',
];

$context['posts'] = Timber::get_posts($args);