EmptySource.php

<?php

namespace Drupal\migrate\Plugin\migrate\source;


/**
 * Source returning a row based on the constants provided.
 *
 * Example:
 *
 * @code
 * source:
 *   plugin: empty
 *   constants:
 *     entity_type: user
 *     field_name: image
 * @endcode
 *
 * This will return a single row containing 'constants/entity_type' and
 * 'constants/field_name' elements, with values of 'user' and 'image',
 * respectively.
 *
 * For additional configuration keys, refer to the parent class:
 * @see \Drupal\migrate\Plugin\migrate\source\SourcePluginBase
 *
 * @MigrateSource(
 *   id = "empty",
 *   source_module = "migrate"
 * )
 */
class EmptySource extends SourcePluginBase {
    
    /**
     * {@inheritdoc}
     */
    public function fields() {
        return [
            'id' => $this->t('ID'),
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function initializeIterator() {
        return new \ArrayIterator([
            [
                'id' => '',
            ],
        ]);
    }
    
    /**
     * Allows class to decide how it will react when it is treated like a string.
     */
    public function __toString() {
        return '';
    }
    
    /**
     * {@inheritdoc}
     */
    public function getIds() {
        $ids['id']['type'] = 'string';
        return $ids;
    }
    
    /**
     * {@inheritdoc}
     */
    protected function doCount() {
        return 1;
    }

}