modules/custom/d_update/src/ConfigManager.php
public function generateHashFromDatabase($configName) {
    $config = \Drupal::config($configName)->getRawData();
    if (empty($config)) {
      return FALSE;
    }

    unset($config['uuid']);
    unset($config['lang']);
    unset($config['langcode']);
    $configString = serialize($config);

    return md5($configString);
  }
public function generateHashFromDatabase($configName) {
    $config = \Drupal::config($configName)->getRawData();
    if (empty($config)) {
      return FALSE;
    }

    unset($config['uuid']);
    unset($config['lang']);
    unset($config['langcode']);
    $configString = serialize($config);

    return md5($configString);
  }
Generates hash for the specified config.

@param string $configName
Full name of the config, eg node.type.content_page.

@return bool|string
Returns hash or false if there is no config with provided name.