Tasks::initializeDatabase

Tasks::initializeDatabase()

function initializeDatabase() {
  // We create some functions using global names instead of prefixing them
  // like we do with table names. This is so that we don't double up if more
  // than one instance of Drupal is running on a single database. We therefore
  // avoid trying to create them again in that case.
  // At the same time checking for the existence of the function fixes
  // concurrency issues, when both try to update at the same time.
  try {
    $connection = Database::getConnection();
    // When testing, two installs might try to run the CREATE FUNCTION queries
    // at the same time. Do not let that happen.
    $connection->query('SELECT pg_advisory_lock(1)');
    // Don't use {} around pg_proc table.
    if (!$connection->query("SELECT COUNT(*) FROM pg_proc WHERE proname = 'rand'")->fetchField()) {
      $connection->query('CREATE OR REPLACE FUNCTION "rand"() RETURNS float AS
          \'SELECT random();\'
          LANGUAGE \'sql\'', 
      [], 
      ['allow_delimiter_in_query' => TRUE]
      );
    }

    if (!$connection->query("SELECT COUNT(*) FROM pg_proc WHERE proname = 'substring_index'")->fetchField()) {
      $connection->query('CREATE OR REPLACE FUNCTION "substring_index"(text, text, integer) RETURNS text AS
          \'SELECT array_to_string((string_to_array($1, $2)) [1:$3], $2);\'
          LANGUAGE \'sql\'', 
      [], 
      ['allow_delimiter_in_query' => TRUE]
      );
    }
    $connection->query('SELECT pg_advisory_unlock(1)');

    $this->pass(t('PostgreSQL has initialized itself.'));
  }
  catch (\Exception $e) {
    $this->fail(t('Drupal could not be correctly setup with the existing database due to the following error: @error.', ['@error' => $e->getMessage()]));
  }
}