code: private function _socialImage ($image, array $transform)
  	{
  		if (!$image) return '';
  
  		$transformUrl = $image->getUrl($transform);
  
  		if ($transformUrl === null)
  			return '';
  
  		if ($transformUrl && strpos($transformUrl, 'http') === false)
  			$transformUrl = UrlHelper::urlWithScheme($transformUrl, (\Craft::$app->getRequest()->getIsSecureConnection()? 'https': 'http'));
  
  		return Template::raw($transformUrl);
  	}
docs: @param Asset|null $image
  @param array      $transform
  
  @return \Twig_Markup|string
  @throws \yii\base\Exception