A Drupal 8 migrate processor plugin for debugging

Debug

<?php

namespace Drupal\uwec_migration\Plugin\migrate\process;

use Drupal\migrate\MigrateExecutableInterface;
use Drupal\migrate\ProcessPluginBase;
use Drupal\migrate\Row;

/**
 * This plugin allows your migration to spit the value to the command line.
 *
 * Usage, sends back an array of values:
 *
 * process:
 *   field_semesters:
 *     plugin: debug
 *     source: semesters
 * Where "semesters" is the name of your source field, and "field_semesters" is the name
 * of the Drupal select field.
 *
 * @MigrateProcessPlugin(
 *   id = "debug"
 * )
 */
class Debug extends ProcessPluginBase {

  /**
   * {@inheritdoc}
   */
  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {

    print_r($value);

    return $value;
  }

}