Snippets - Code for Drupal

public function getCacheMaxAge() {
  // Disable block cache.
  return 0;
}

~/composer clear-cache

$bid = 20 // Get the block id through config, SQL or some other means.
$block = \Drupal\block_content\Entity\BlockContent::load($bid); // Load block entity.
$render = \Drupal::entityTypeManager()->
  getViewBuilder('block_content')->view($block);
return $render;

/**
 * Implements hook_post_update_NAME().
 */
function MODULE_post_update_api_data_value(&$sandbox) {

  if (!isset($sandbox['total'])) {
  // Get API Data content type nid's.
    $nids = Drupal::entityQuery('node')
      ->condition('type', 'apidata')
      ->execute();
    $sandbox['total'] = count($nids);
    $sandbox['current'] = 0;
  }

  $nodes_per_batch = 50;
  $nids = Drupal::entityQuery('node')
    ->condition('type', 'apidata')
    ->range($sandbox['current'], $nodes_per_batch)
    ->execute();

  foreach ($nids as $nid) {
    $node = Drupal::entityTypeManager()
      ->getStorage('node')
      ->load($nid);

	// Check if the field is empty.
    if (empty($node->field_api_target->value)) {
      // If is empty, set default value (0).
      $node->field_api_target->value = 0;
    }

    $node->save();
    $sandbox['current']++;
  }

  if ($sandbox['total'] === 0) {
    // Until it is finished, the batch does not stop.
    $sandbox['#finished'] = 1;
  }
  else {
    // Indicates the percentage of the completed.
    $sandbox['#finished'] = ($sandbox['current'] / $sandbox['total']);
  }
}

drush eval "print_r(array_keys(entity_get_info()));"