dgi_image_discovery.install

<?php

/**
 * @file
 * Module installation hook implementations.
 */

use Drupal\field\Entity\FieldConfig;
use Drupal\field\Entity\FieldStorageConfig;

/**
 * Implements hook_update_N().
 */
function dgi_image_discovery_update_8001() {
  $field_name = 'field_default_image';
  $vocabulary_name = 'islandora_models';
  $entity_type = 'taxonomy_term';

  // Check if the field storage exists.
  if (!\Drupal::service('entity_type.manager')->getStorage('field_storage_config')->load("$entity_type.$field_name")) {
    // Create field storage.
    FieldStorageConfig::create([
      'field_name' => $field_name,
      'entity_type' => $entity_type,
      'type' => 'image',
      'settings' => [],
    ])->save();
  }

  // Check if the field exists.
  if (!\Drupal::service('entity_type.manager')->getStorage('field_config')->load("$entity_type.$vocabulary_name.$field_name")) {
    // Create field instance.
    FieldConfig::create([
      'field_storage' => \Drupal::service('entity_type.manager')->getStorage('field_storage_config')->load("$entity_type.$field_name"),
      'bundle' => $vocabulary_name,
      'label' => 'Default Image',
      'settings' => [],
    ])->save();
  }

  // Add the field to the default form display.
  $form_display = \Drupal::service('entity_type.manager')->getStorage('entity_form_display')->load("$entity_type.$vocabulary_name.default");
  if ($form_display) {
    $form_display->setComponent($field_name, [
      'type' => 'image_image',
      'weight' => 5,
    ])->save();
  }

  // Add the field to the default view display.
  $view_display = \Drupal::service('entity_type.manager')->getStorage('entity_view_display')->load("$entity_type.$vocabulary_name.default");
  if ($view_display) {
    $view_display->setComponent($field_name, [
      'label' => 'above',
      'type' => 'image',
      'weight' => 5,
      'settings' => [
        'image_style' => 'thumbnail',
        'image_link' => 'content',
      ],
    ])->save();
  }
}