<?php

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

$storages = [];
for ($i = 0; $i < 100; $i++) {
  $storages[$i] = FieldStorageConfig::create([
    'field_name' => 'field_map_storage_' . $i,
    'entity_type' => 'contact_message',
    'type' => 'text',
  ]);
  $storages[$i]->save();
}

$start = microtime(TRUE);

for ($i = 0; $i < 500; $i++) {
  $bundle_start = microtime(TRUE);
  $form = ContactForm::create([
    'id' => 'field_map_' . $i,
    'label' => 'Contact form ' . $i,
  ]);
  $form->save();

  $field_index = 0;
  foreach (array_rand($storages, 20) as $storage_key) {
    FieldConfig::create(array(
      'field_storage' => $storages[$storage_key],
      'label' => 'Field on ' . $form->label() . ' #' . $field_index++,
      'bundle' => $form->id(),
    ))->save();
  }

  print "$i: Created bundle with 20 fields in " . round(microtime(TRUE) - $bundle_start, 2) . "s\n";

}


print "$i: Created 100 bundle with 20 fields each in " . round(microtime(TRUE) - $start, 2) . "s\n";