Posted at 2018-07-12

Gravでリンクカードを作る

More than 1 year has passed since last update.

リンクカードプラグインが無いっぽい感じがしたので作りました。

とはいえShortcode Coreプラグインを利用してカスタムショートコードを作っただけですが。

LinkcardShortcode.php

<?php

namespace Grav\Plugin\Shortcodes;

use Thunder\Shortcode\Shortcode\ShortcodeInterface;

use Thunder\Shortcode\Shortcode\ProcessedShortcode;

class LinkcardShortcode extends Shortcode {

    public function init() {

        $this->shortcode->getHandlers()->add('site', function(ProcessedShortcode $sc) {

            $url = $sc->getParameter('url');

            $purl = parse_url($url);

            $img = $sc->getParameter('img');

            $content = $sc->getContent();

            $html = null;

            if($url){

                $data = $this->get_ogp($url,$img,$content);

                $img = $data['img'];

                $title = $data['title'];

                $desc = $data['desc'];

                $html = '<blockquote class="link panel panel-default"><a onclick="ga(\'send\',\'event\',\'BlogCard\',\'click\',location.href);" rel="noopener" target="_blank" href="'.$url.'">';

                $html .= '<img class="thumb pull-right" src="'.$img.'" alt="'.$title.'" /><span class="lead text-primary">'.$title.'</span>';

                $html .= '<p>'.$desc.'</p><footer><img class="favicon" src="//www.google.com/s2/favicons?domain_url='.urlencode($url).'" /> '.$purl['host'].'</footer><div class="clearfix"></div></a></blockquote>';

            }

            return $html;

        });

    }

    private function get_ogp($url,$img = null,$title = null){

        $context = stream_context_create(array(

        'http' => array('ignore_errors' => true)

        ));

        $html = file_get_contents($url, false, $context);

        $description = null;

        $thumb = null;

        if($html){

            preg_match('/<title>(.*)<\/title>/',$html,$mt);

            if($mt && $mt[1]){$title = $mt[1];}

            preg_match('/<meta property="og:image" content="http([^\n]*)"/',$html,$mi);

            if($mi && $mi[1]){$thumb = 'http'.$mi[1];}

            preg_match('/<meta name="description" content="([^\n]*)"/',$html,$md);

            if($md && $md[1]){$description = $md[1];}

            else{

                preg_match('/<meta property="og:description" content="([^\n]*)"/',$html,$md);

                if($md && $md[1]){$description = $md[1];}

            }

        }

        if($img){$thumb = $img;}

        elseif(!$thumb){$thumb = '/empty.gif';}

        $data = array(

            'title' => $title,

            'img' => $thumb,

            'desc' => mb_substr($description,0,200)

        );

        return $data;

    }

}