Your IP : 3.22.242.43
<?php
namespace Bitrix\Main\UrlPreview;
use Bitrix\Main\Context;
use Bitrix\Main\Text\Encoding;
use Bitrix\Main\Type\DateTime;
use Bitrix\Main\Web\HttpClient;
use Bitrix\Main\Web\Uri;
use Bitrix\Main\Web\MimeType;
class HtmlDocument
{
const MAX_IMAGES = 4;
const MAX_IMAGE_URL_LENGTH = 2000;
const MAX_HTML_LENGTH = 1048576; // 1 MB
/** @var Uri */
protected $uri;
/** @var string */
protected $html;
/** @var string */
protected $htmlEncoding;
/** @var array
* Allowed keys so far: TITLE, DESCRIPTION, IMAGE
*/
protected $metadata = array(
"TITLE" => null,
"DESCRIPTION" => null,
"IMAGE" => null,
"EMBED" => null,
"DATE_EXPIRE" => null,
);
/** @var array */
protected $metaElements = array();
/** @var array */
protected $linkElements = array();
/**
* HtmlDocument constructor.
*
* @param string $html Document HTML code.
* @param Uri $uri Document's URL.
*/
public function __construct($html, Uri $uri)
{
$this->html = substr($html, 0, self::MAX_HTML_LENGTH);
$this->uri = $uri;
}
/**
* Returns Uri of the document
*
* @return Uri
*/
public function getUri()
{
return $this->uri;
}
/**
* Returns full html code of the document
*
* @return string
*/
public function getHtml()
{
return $this->html;
}
/**
* Returns true if metadata is complete
*
* @return bool
*/
public function checkMetadata()
{
$result = ( $this->metadata['TITLE'] != ''
&& $this->metadata['DESCRIPTION'] != ''
&& $this->metadata['IMAGE'] != '');
if ($this->isEmbeddingAllowed())
{
$result = $result && $this->metadata['EMBED'] != '';
}
return $result;
}
/**
* Returns metadata, extracted from the page. Should return an array with required key TITLE
* and optional keys DESCRIPTION and URL
*
* @return array|false
*/
public function getMetadata()
{
return $this->metadata;
}
/**
* Returns document's TITLE metadata
*
* @return string
*/
public function getTitle()
{
return $this->metadata['TITLE'];
}
/**
* Sets document's TITLE metadata
*
* @param string $title Title.
* @return void
*/
public function setTitle($title)
{
if ($title <> '')
{
$this->metadata['TITLE'] = $this->filterString($title);
}
}
/**
* @return string
*/
public function getDescription()
{
return $this->metadata['DESCRIPTION'];
}
/**
* Sets document's DESCRIPTION metadata
*
* @param string $description Description.
* @return void
*/
public function setDescription($description)
{
if ($description <> '')
{
$this->metadata['DESCRIPTION'] = $this->filterString($description);
}
}
/**
* @return string Main image's url.
*/
public function getImage()
{
return $this->metadata['IMAGE'];
}
/**
* Sets document's IMAGE metadata
*
* @param string $image Main image's url.
* @return void
*/
public function setImage($image)
{
if ($image <> '')
{
$imageUrl = $this->normalizeImageUrl($image);
if (!is_null($imageUrl) && $this->validateImage($imageUrl, true))
{
$this->metadata['IMAGE'] = $imageUrl;
}
}
}
/**
* @return string HTML code to embed url to the page.
*/
public function getEmdbed()
{
return $this->metadata['EMBED'];
}
/**
* Sets document's EMBED metadata, if site is allowed to be embedded.
*
* @param string $embed HTML code for embedding object to the page.
* @return void
*/
public function setEmbed($embed)
{
if ($this->isEmbeddingAllowed())
{
$this->metadata['EMBED'] = $embed;
}
}
/**
* Sets additional metadata field.
* @param string $fieldName Name of the field. Expected values:
* <li>FAVICON: $fieldValue must contain the url of document's favicon
* <li>IMAGES: $fieldValue must be the array of urls of images, detected in the document
* <li>In other cases, $fieldValue must contain plain text.
* @param string $fieldValue Field value.
* @return void
*/
public function setExtraField($fieldName, $fieldValue)
{
if ($fieldName == 'FAVICON')
{
$this->metadata['EXTRA'][$fieldName] = $this->convertRelativeUriToAbsolute($fieldValue);
}
elseif ($fieldName == 'IMAGES')
{
if (is_array($fieldValue))
{
$this->metadata['EXTRA']['IMAGES'] = array();
foreach($fieldValue as $image)
{
$image = $this->normalizeImageUrl($image);
if ($image)
{
$this->metadata['EXTRA']['IMAGES'][] = $image;
}
if (count($this->metadata['EXTRA']['IMAGES']) >= self::MAX_IMAGES)
{
break;
}
}
}
}
else
{
$this->metadata['EXTRA'][$fieldName] = $this->filterString($fieldValue);
}
}
/**
* Returns value of the additional metadata field
* @param string $fieldName Name of the field.
* @return string|null Value of the additional metadata field.
*/
public function getExtraField($fieldName)
{
return $this->metadata['EXTRA'][$fieldName] ?? null;
}
/**
* Sets Expire date for the metadata.
*
* @param DateTime $dateExpire
*/
public function setDateExpire(DateTime $dateExpire)
{
if (!isset($this->metadata['DATE_EXPIRE']) || $this->metadata['DATE_EXPIRE']->getTimestamp() > $dateExpire->getTimestamp())
{
$this->metadata['DATE_EXPIRE'] = $dateExpire;
}
}
/**
* Returns expire date for the metadata.
*
* @return DateTime|null
*/
public function getDateExpire(): ?DateTime
{
return $this->metadata['DATE_EXPIRE'];
}
/**
* Set HTML document encoding
*
* @param string $encoding Document's encoding.
* @return void
*/
public function setEncoding($encoding)
{
$encoding = trim($encoding, " \t\n\r\0\x0B'\"");
$this->htmlEncoding = $encoding;
}
/**
* @return string Document encoding.
*/
public function getEncoding()
{
if ($this->htmlEncoding <> '')
{
return $this->htmlEncoding;
}
$this->htmlEncoding = $this->detectEncoding();
return $this->htmlEncoding;
}
/**
* Auto-detect and set HTML document encoding
*
* @return string Detected encoding.
*/
public function detectEncoding()
{
$result = '';
if (empty($this->metaElements))
{
$this->metaElements = $this->extractElementAttributes('meta');
}
foreach($this->metaElements as $metaElement)
{
if (isset($metaElement['http-equiv']) && mb_strtolower($metaElement['http-equiv']) == 'content-type')
{
if (preg_match('/charset=([\w\-]+)/', $metaElement['content'], $matches))
{
$result = $matches[1];
break;
}
}
elseif (isset($metaElement['charset']))
{
$result = $metaElement['charset'];
break;
}
}
return $result;
}
/**
* Parses html content for attributes of the specified elements and fills $destination array with found attributes
*
* @param string $tagName Name of the tag.
* @return array
*/
public function extractElementAttributes($tagName)
{
$results = array();
preg_match_all("/<$tagName.+?>/mis", $this->html, $elements);
foreach($elements[0] as $element)
{
preg_match_all('/(?:([\w\-_]+)=([\'"])(.*?)\g{-2}\s*)/mis', $element, $matches);
$elementAttributes = array();
foreach($matches[1] as $k => $attributeName)
{
$attributeName = mb_strtolower($attributeName);
$attributeValue = $matches[3][$k];
$elementAttributes[$attributeName] = $attributeValue;
}
$results[] = $elementAttributes;
}
return $results;
}
/**
* Returns value of the content attribute
*
* @param string $name Value of a name or property attribute.
* @return string
* */
public function getMetaContent($name)
{
if (empty($this->metaElements))
{
$this->metaElements = $this->extractElementAttributes('meta');
}
$name = mb_strtolower($name);
foreach ($this->metaElements as $metaElement)
{
if ((isset($metaElement['name']) && mb_strtolower($metaElement['name']) === $name
|| isset($metaElement['property']) && mb_strtolower($metaElement['property']) === $name)
&& $metaElement['content'] <> '')
{
return $metaElement['content'];
}
}
return null;
}
/**
* Returns value of the href attribute.
*
* @param string $rel Value of the rel attribute.
* @return string
*/
public function getLinkHref($rel)
{
if (empty($this->linkElements))
{
$this->linkElements = $this->extractElementAttributes('link');
}
$rel = mb_strtolower($rel);
foreach ($this->linkElements as $linkElement)
{
if (isset($linkElement['rel'])
&& mb_strtolower($linkElement['rel']) == $rel
&& $linkElement['href'] <> '')
{
return $linkElement['href'];
}
}
return null;
}
/**
* Sanitizes string and converts it to the site's charset.
*
* @param string $str Input string.
* @return string
*/
protected function filterString($str)
{
$str = html_entity_decode($str, ENT_QUOTES, $this->getEncoding());
$str = Encoding::convertEncoding($str, $this->getEncoding(), Context::getCurrent()->getCulture()->getCharset());
$str = trim($str);
$str = strip_tags($str);
return $str;
}
/**
* Converts relative url to the absolute, considering document's url.
* @param string $uri Relative url.
* @return null|string Absolute url or null if relative url contains errors.
*/
protected function convertRelativeUriToAbsolute($uri)
{
if (strpos($uri, '//') === 0)
{
$uri = $this->uri->getScheme().":".$uri;
}
if (preg_match('#^https?://#', $uri))
{
return $uri;
}
$pars = parse_url($uri);
if ($pars === false)
{
return null;
}
if (isset($pars['host']))
{
$result = $uri;
}
elseif (isset($pars['path']))
{
if (mb_substr($pars['path'], 0, 1) !== '/')
{
$pathPrefix = preg_replace('/^(.+?)([^\/]*)$/', '$1', $this->uri->getPath());
$pars['path'] = $pathPrefix.$pars['path'];
}
$uriPort = '';
if ($this->uri->getScheme() === 'http' && $this->uri->getPort() != '80'
|| $this->uri->getScheme() === 'https' && $this->uri->getPort() != '443')
{
$uriPort = ':'.$this->uri->getPort();
}
$result = $this->uri->getScheme().'://'
.$this->uri->getHost()
.$uriPort
.$pars['path']
.(isset($pars['query']) ? '?'.$pars['query'] : '')
.(isset($pars['fragment']) ? '#'.$pars['fragment'] : '');
}
else
{
$result = null;
}
return $result;
}
/**
* Transforms image's URL from relative to absolute and checks length of the resulting URL.
* @param string $url Image's URL.
* @return string|null Absolute image's URL, or null if URL is incorrect or too long.
*/
protected function normalizeImageUrl($url): ?string
{
$url = $this->convertRelativeUriToAbsolute($url);
if (mb_strlen($url) > self::MAX_IMAGE_URL_LENGTH)
{
$url = null;
}
return $url;
}
/**
* Validates mime-type of the image
* @param string $url Absolute image's URL.
* @return bool
*/
protected function validateImage($url, $skipForPrivateIp = false)
{
$httpClient = new HttpClient();
$httpClient->setTimeout(5);
$httpClient->setStreamTimeout(5);
$httpClient->setPrivateIp(false);
$httpClient->setHeader('User-Agent', UrlPreview::USER_AGENT);
if (!$httpClient->query('HEAD', $url))
{
$errorCode = array_key_first($httpClient->getError());
return ($skipForPrivateIp && $errorCode === 'PRIVATE_IP');
}
if ($httpClient->getStatus() !== 200)
{
return false;
}
$contentType = $httpClient->getHeaders()->getContentType();
return MimeType::isImage($contentType);
}
/**
* Returns true if document's site is allowed to be embedded.
* @return bool
*/
protected function isEmbeddingAllowed()
{
return UrlPreview::isHostTrusted($this->uri);
}
}