Use of Drupal TempStore API

TempStore API: A key-value storage to keep temporary data (private or shared) across page requests.

• Set the value using the Drupal service private_tempstore:

  $tempstore = \Drupal::service('user.private_tempstore')->get('module_name');
  $tempstore->set('foo', 'bar');

• Get value using the Drupal service private_tempstore:

  $tempstore = \Drupal::service('user.private_tempstore')->get('module_name');
  $myKey = $tempstore->get('foo');

• By default, it keeps the value stored for a week, while you can also delete the value using the delete function.

  $tempstore = \Drupal::service('user.private_tempstore')->get('module_name');
  $store->delete('foo');