oembed.php

<?php
 
namespace Bitrix\Main\UrlPreview\Parser;
 
use Bitrix\Main\Text\Encoding;
use Bitrix\Main\UrlPreview\UrlPreview;
use Bitrix\Main\Web\HttpClient;
use Bitrix\Main\UrlPreview\HtmlDocument;
use Bitrix\Main\UrlPreview\Parser;
 
class Oembed extends Parser
{
    const OEMBED_TYPE_XML = "text/xml+oembed";
    const OEMBED_TYPE_JSON ="application/json+oembed";
 
    protected $metadataType;
 
    protected $metadataUrl;
 
    protected $metadataEncoding;
 
    public function handle(HtmlDocument $document, HttpClient $httpClient = null)
    {
        if(!$this->detectOembedLink($document) || $this->metadataUrl == '')
        {
            return;
        }
 
        $isHttpClientPassed = true;
        if(!$httpClient)
        {
            $httpClient = $this->initHttpClient();
            $isHttpClientPassed = false;
        }
        $rawMetadata = $this->getRawMetaData($httpClient);
        // if request was served through http - try to switch to https
        if(
            (
                !$rawMetadata
                || $httpClient->getStatus() === 403
            )
            && mb_strpos($this->metadataUrl, 'http://') === 0)
        {
            if(!$isHttpClientPassed)
            {
                $httpClient = $this->initHttpClient();
            }
            $metadataUrl = str_replace('http://', 'https://', $this->metadataUrl);
            $rawMetadata = $httpClient->get($metadataUrl);
        }
 
        if($rawMetadata === false)
        {
            return;
        }
 
        $parsedMetadata = $this->parseMetadata($rawMetadata);
        if($parsedMetadata !== false)
        {
            if($this->metadataEncoding <> '' && $document->getEncoding() !== $this->metadataEncoding)
            {
                $parsedMetadata = Encoding::convertEncoding($parsedMetadata, $this->metadataEncoding, $document->getEncoding());
            }
 
            if($document->getTitle() == '' && !empty($parsedMetadata['title']))
            {
                $document->setTitle($parsedMetadata['title']);
            }
 
            if($document->getImage() == '' && !empty($parsedMetadata['thumbnail_url']))
            {
                $document->setImage($parsedMetadata['thumbnail_url']);
            }
 
            if($document->getEmdbed() == '' && !empty($parsedMetadata['html']))
            {
                $document->setEmbed($parsedMetadata['html']);
            }
 
            if($document->getExtraField('PROVIDER_NAME') == '' && !empty($parsedMetadata['provider_name']))
            {
                $document->setExtraField('PROVIDER_NAME', $parsedMetadata['provider_name']);
            }
 
            if($document->getExtraField('VIDEO_WIDTH') == '' && !empty($parsedMetadata['width']))
            {
                $document->setExtraField('VIDEO_WIDTH', $parsedMetadata['width']);
            }
 
            if($document->getExtraField('VIDEO_HEIGHT') == '' && !empty($parsedMetadata['height']))
            {
                $document->setExtraField('VIDEO_HEIGHT', $parsedMetadata['height']);
            }
        }
    }
 
    protected function detectOembedLink(HtmlDocument $document)
    {
        preg_match_all('/<link[^>]*rel\s*=\s*["\']?alternate["\']?[^>]*?>/', $document->getHtml(), $linkElements);
 
        foreach($linkElements[0] as $linkElement)
        {
            $typeJson = (strpos($linkElement, $this::OEMBED_TYPE_JSON) !== false);
            $typeXml = (strpos($linkElement, $this::OEMBED_TYPE_XML) !== false);
            if($typeJson || $typeXml)
            {
                if(preg_match('/href=[\'"](.+?)[\'"]/', $linkElement, $attributes))
                {
                    $this->metadataType = ($typeJson ? 'json' : 'xml');
                    $this->metadataUrl = htmlspecialcharsback($attributes[1]);
                    return true;
                }
            }
        }
 
        return false;
    }
 
    protected function parseMetadata($rawMetadata)
    {
        switch($this->metadataType)
        {
            case 'json':
                return $this->parseJsonMetadata($rawMetadata);
                break;
            case 'xml':
                return $this->parseXmlMetadata($rawMetadata);
                break;
        }
 
        return false;
    }
 
    protected function parseJsonMetadata($rawMetadata)
    {
        $parsedMetadata = json_decode($rawMetadata, true);
        $this->metadataEncoding = 'UTF-8';
 
        return $parsedMetadata;
    }
 
    protected function parseXmlMetadata($rawMetadata)
    {
        $xml = new \CDataXML();
        if($xml->LoadString($rawMetadata))
        {
            //detect xml encoding
            if(preg_match('/<\?xml[^>]+?encoding=[\'"](.+?)[\'"]\?>/', $rawMetadata, $matches))
                $this->metadataEncoding = $matches[1];
            else
                $this->metadataEncoding = 'UTF-8';
 
            $result = array();
            $dom = $xml->GetTree();
            $mainNode = $dom->elementsByName('oembed');
            foreach($mainNode[0]->children as $node)
            {
                $result[$node->name] = $node->content;
            }
            return $result;
        }
 
        return false;
    }
 
    protected function getRawMetaData(HttpClient $httpClient)
    {
        $rawMetadata = $httpClient->get($this->metadataUrl);
 
        return $rawMetadata;
    }
 
    protected function initHttpClient(): HttpClient
    {
        $httpClient = new HttpClient();
        $httpClient->setTimeout(5);
        $httpClient->setStreamTimeout(5);
        $httpClient->setHeader('User-Agent', UrlPreview::USER_AGENT, true);
        $httpClient->setPrivateIp(false);
 
        return $httpClient;
    }
}