protected function processConfig(array $config)
    {
        return [
            'model'      => $config['model'],
            'table'      => $this->getModelTable($config['model']),
            'field'      => snake_case($config['field']),
            'key'        => snake_case($this->key($config['key'])),
            'foreignKey' => snake_case($this->key($config['foreignKey'])),
        ];
    }