Extending eZ Studio with new blocks

blocks.yml

blocks:
    custom:
        views:
            custom:
                template: MyBlockBundle::custom.html.twig
                name: My Custom Block view

custom.html.twig

<h3>My Custom block</h3>
{{ block }}

CustomBlock.php

<?php

namespace My\BlockBundle\Block;

use EzSystems\LandingPageFieldTypeBundle\Exception\InvalidBlockAttributeException;
use EzSystems\LandingPageFieldTypeBundle\FieldType\LandingPage\Definition\BlockDefinition;
use EzSystems\LandingPageFieldTypeBundle\FieldType\LandingPage\Definition\BlockAttributeDefinition;
use EzSystems\LandingPageFieldTypeBundle\FieldType\LandingPage\Model\AbstractBlockType;
use EzSystems\LandingPageFieldTypeBundle\FieldType\LandingPage\Model\BlockValue;

class CustomBlock extends AbstractBlockType
{
    /*
     * With this method you can return values that will be used in the template as variables.
     */
    public function getTemplateParameters(BlockValue $blockValue)
    {        
        return [
            'block' => json_encode($blockValue->getAttributes())
        ];
    }
    
    /*
     * Creates block definition with fields
     */
    public function createBlockDefinition()
    {
        return new BlockDefinition(
            'custom', // Block type (unique)
            'Custom Block', // Name of block
            'default', // Block category (currently unsupported)
            'bundles/ezsystemslandingpagefieldtype/images/thumbnails/tag.svg', // block thumbnail; will be used in the eZ Studio blocks sidebar
            [], // extra views - the hardcoded template
            [
                new BlockAttributeDefinition(
                    'content', // Attribute's ID (unique)
                    'Content', // Attribute' name
                    'text', // Attribute's type
                    '/[^\\s]/', // regex for frontend validation
                    'The content value should be a text', // regex validation fail message
                    true, // is field required?
                    false, // should this attribute input be displayed inline to the previous?
                    [], // default value
                    [] // available options (only for select and multiple field types)
                ),
                
                new BlockAttributeDefinition(
                    'contentStyle',
                    'Content Style',
                    'select',
                    '',
                    'Please, select a style',
                    false,
                    false,
                    ['default'],
                    [
                        'default'   => 'Default style',
                        'flat'      => 'Flat style',
                        'rounded'   => 'Rounded style'
                    ]
                ),
            ]
        );
    }
    
    /*
     * Validates user input from the block configuration form
     */
    public function checkAttributesStructure(array $attributes)
    {
        if (!isset($attributes['content'])) {
            throw new InvalidBlockAttributeException(
                $this->getBlockDefinition()->getName(),
                'content',
                'Content must be set.'
            );
        }
    }
}

CustomBlockExtension.php

<?php

namespace My\BlockBundle\DependencyInjection;

use Symfony\Component\Config\Resource\FileResource;
use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\Config\FileLocator;
use Symfony\Component\DependencyInjection\Extension\PrependExtensionInterface;
use Symfony\Component\HttpKernel\DependencyInjection\Extension;
use Symfony\Component\DependencyInjection\Loader;
use Symfony\Component\Yaml\Yaml;

class CustomBlockExtension extends Extension implements PrependExtensionInterface
{
    public function load(array $configs, ContainerBuilder $container)
    {
        $configuration = new Configuration();
        $config = $this->processConfiguration($configuration, $configs);

        $loader = new Loader\YamlFileLoader($container, new FileLocator(__DIR__.'/../Resources/config'));
        $loader->load('services.yml');
    }

    public function prepend(ContainerBuilder $container)
    {
        $configFile = __DIR__ . '/../Resources/config/blocks.yml';
        $config = Yaml::parse(file_get_contents($configFile));
        $container->prependExtensionConfig('ez_systems_landing_page_field_type', $config);
        $container->addResource(new FileResource($configFile));
    }
}

services.yml

services:
    my.block.custom:
        class: My\BlockBundle\Block\CustomBlock
        tags:
            - { name: landing_page_field_type.block_type, alias: custom }