function getLinkPreview($url){
    if($url == null || $url == ''){
        return [];
    }
    try {

        $doc = new DOMDocument();
        $data = file_get_contents($url);
        @$doc->loadHTML($data);
        $rv = array(
            'title' => '',
            'url' => $url,
            'description' => '',
            'image' => '',
        );

        // meta name="title"
        // meta name="og:title"
        // title
        $_title = $doc->getElementsByTagName('title');
        foreach($_title as $_ttl){
            $rv['title'] = $_ttl->textContent;
        }

        // meta name="description"
        // meta name="og:description"
        // meta name="image"
        // meta name="og:image"
        $_meta = $doc->getElementsByTagName('meta');
        if($rv['description'] == ''){
            foreach($_meta as $_des){
                $_mName = $_des->getAttribute('name');
                if($_mName == 'description'){
                    $rv['description'] = $_des->getAttribute('content');
                }
            }
            if($rv['description'] == ''){
                foreach($_meta as $_des){
                    $_mName = $_des->getAttribute('property');
                    if($_mName == 'description'){
                        $rv['description'] = $_des->getAttribute('content');
                    }
                }
            }
            if($rv['description'] == ''){
                foreach($_meta as $_des){
                    $_mName = $_des->getAttribute('name');
                    if($_mName == 'og:description'){
                        $rv['description'] = $_des->getAttribute('content');
                    }
                }
            }
            if($rv['description'] == ''){
                foreach($_meta as $_des){
                    $_mName = $_des->getAttribute('property');
                    if($_mName == 'og:description'){
                        $rv['description'] = $_des->getAttribute('content');
                    }
                }
            }
        }
        if($rv['image'] == ''){
            foreach($_meta as $_des){
                $_mName = $_des->getAttribute('name');
                if($_mName == 'image'){
                    $rv['image'] = $_des->getAttribute('content');
                }
            }
            if($rv['image'] == ''){
                foreach($_meta as $_des){
                    $_mName = $_des->getAttribute('property');
                    if($_mName == 'image'){
                        $rv['image'] = $_des->getAttribute('content');
                    }
                }
            }
            if($rv['image'] == ''){
                foreach($_meta as $_des){
                    $_mName = $_des->getAttribute('name');
                    if($_mName == 'og:image'){
                        $rv['image'] = $_des->getAttribute('content');
                    }
                }
            }
            if($rv['image'] == ''){
                foreach($_meta as $_des){
                    $_mName = $_des->getAttribute('property');
                    if($_mName == 'og:image'){
                        $rv['image'] = $_des->getAttribute('content');
                    }
                }
            }
        }
        if($rv['image'] == ''){
            $_imgs = $doc->getElementsByTagName('img');
            if(count($_imgs) > 0){
                $rv['image'] = $_imgs[0]->getAttribute('src');
            }
        }
        $rv['title'] = str_replace("'","’",$rv['title']);
        $rv['description'] = str_replace("'","’",$rv['description']);
        return $rv;

    } catch (Exception $e){
        $rv = array(
            'title' => '',
            'url' => $url,
            'description' => '',
            'image' => '',
        );
        return $rv;
    }
}