public function parse($configFile = '')
    {
        // Load default configuration
        $defaultConfigFile = $this->getConfigFile($configFile, 'default');
        $defaultConfigArray = parent::parse($defaultConfigFile) ?: [];

        // Load environment configuration
        $envConfigFile = $this->getConfigFile($configFile, $this->app->getEnvironment());
        $envConfigArray = parent::parse($envConfigFile) ?: [];

        // Merge environment config to default and set to application
        return ArrayHelper::merge($defaultConfigArray, $envConfigArray, $deep = true);
    }