Drupal 8 - Find or Create Taxonomy Trait

FindOrCreateTaxonomyTrait.php

<?php

namespace Drupal\MY_MODULE_NAME;

use Drupal\Core\Entity\EntityStorageException;
use Drupal\taxonomy\Entity\Term;

trait FindOrCreateTaxonomyTrait {

  /**
   * Find or create a new taxonomy
   *
   * @param null $name
   * @param null $vid
   *
   * @return int
   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
   */
  public function findOrCreateTaxonomy($name = NULL, $vid = NULL) {
    // Truncate to 255 characters, this is taxonomy term name limit
    $name = substr($name, 0, 255);

    // look up the term
    $find = self::getTidByName($name, $vid);
    // can find a term return the tid
    if ($find > 0) {
      return $find;
    }
    // otherwise create a new term
    return self::createTerm($name, $vid);
  }

  /**
   * Utility: find term by name and vid.
   *
   * @param null $name - Term name
   * @param null $vid - Term vid
   *
   * @return int - Term id or 0 if none.
   * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
   * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
   */
  public function getTidByName($name = NULL, $vid = NULL) {
    $properties = [];
    if (!empty($name)) {
      $properties['name'] = $name;
    }
    if (!empty($vid)) {
      $properties['vid'] = $vid;
    }
    $terms = \Drupal::entityManager()
      ->getStorage('taxonomy_term')
      ->loadByProperties($properties);
    $term = reset($terms);

    return !empty($term) ? $term->id() : 0;
  }


  /**
   * @param null $name
   * @param null $vid
   *
   * @return int
   */
  public function createTerm($name = NULL, $vid = NULL) {
    try {
      $term = Term::create([
        'name' => $name,
        'vid' => $vid,
      ])->save();
      return $term;
    } catch (EntityStorageException $e) {
      die($e->getMessage());
    }
  }

}