Content processors

Content processor are the main entry point for custom behaviours in Stenope.

What are processors

A processor acts on the raw content loaded from your sources as an array, before denormalization into its model.

Writing a custom processor allow you to apply virtually any modification to the decoded content before denormalization.

Internally, Stenope registers default processors for:

• Syntax highlighting for code blocks.
• Adding id html attribute to titles and images.
• Providing a lastModified property to contents based on their source last modification.
• ...

Writing a custom processor

To write your own processor, just implements the Stenope\Bundle\Behaviour\ProcessorInterface interface:

<?php

namespace App\Stenope\Processor;

use App\Model\User;
use Stenope\Bundle\Behaviour\ProcessorInterface;
use Stenope\Bundle\Content;

/**
 * Load avatar from Gravatar for users
 */
class GravatarProcessor implements ProcessorInterface
{
    /**
     * Apply modifications to decoded data before denormalization
     *
     * @param array   $data    The decoded data
     * @param string  $type    The model being processed (FQN)
     * @param Content $content The source content
     */
    public function __invoke(array &$data, Content $content): void
    {
        // Only apply this processor on Users
        if (!is_a($content->getType(), User::class, true)) {
            return;
        }

        // Ingore if url is already explicitly specified
        if (\array_key_exists('avatar', $data)) {
            return;
        }

        // Generate Gravatar url from email address
        $data['avatar'] = 'https://www.gravatar.com/avatar/' . md5(strtolower(trim($data['email'])));
    }
}

That's it!

Note: See Stenope's own processors for more examples.

Ordering processor

Processor are applied one after another, and a Processor A can modify the $data that will then be used by a processor B.

To control processor execution order, use the priority tag property:

App\Stenope\Processor\TableOfContentProcessor:
        tags: [{ name: stenope.processor, priority: -10 }]

Note: High priority are executed first, lower priority (typically negative ones) are executed last.