drupal_module__reinstall/src/Plugin/migrate/source/SimpleSourceTrait.php

<?php
/**
 * Created by PhpStorm.
 * User: fgm
 * Date: 11/04/2017
 * Time: 08:35
 */

namespace Drupal\reinstall\Plugin\migrate\source;


trait SimpleSourceTrait {

  protected $sstEntityTypeBundleInfo;

  protected $sstEntityFieldManager;

  protected $sstEntityType;

  protected function getEntityTypeBundleInfo() {
    if (!isset($this->sstEntityTypeBundleInfo)) {
      $this->sstEntityTypeBundleInfo = \Drupal::service('entity_type.bundle.info');
    }

    return $this->sstEntityTypeBundleInfo;
  }

  protected function getEntityFieldManager() {
    if (!isset($this->sstEntityFieldManager)) {
      $this->sstEntityFieldManager = \Drupal::service('entity_field.manager');
    }

    return $this->sstEntityFieldManager;
  }

  protected function getEntityType() {
    assert(isset($this->sstEntityType));
    return $this->sstEntityType;
  }

  /**
   * {@inheritdoc}
   */
  public function fields() {
    $bundles = $this->getEntityTypeBundleInfo()
      ->getBundleInfo($typeName = $this->getEntityType());
    $rows = [];

    foreach ($bundles as $bundleName => $bundle) {
      $fieldDefinitions = $this->getEntityFieldManager()
        ->getFieldDefinitions($typeName, $bundleName);
      foreach ($fieldDefinitions as $fieldName => $fieldDefinition) {
        $rows[$fieldName][$bundleName] = $fieldDefinition->getLabel();
      }
    }

    $fields = [];
    $singleBundle = count($bundles) === 1;
    foreach ($rows as $fieldName => $labels) {
      if ($singleBundle) {
        $fields[$fieldName] = reset($labels);
        continue;
      }

      if (count(array_unique($labels)) === 1) {
        $fields[$fieldName] = reset($labels);
        continue;
      }

      $ret = [];
      ksort($labels);
      foreach ($labels as $ct => $label) {
        $ret[] = $this->t('@ct: @label', ['@ct' => $ct, '@label' => $label]);
      }
      $fields[$fieldName] = implode(', ', $ret);
    }

    ksort($fields);
    return $fields;
  }

}