friendica/src/Content/OEmbed.php

413 lines
12 KiB
PHP

<?php
/**
* @file src/Content/OEmbed.php
*/
namespace Friendica\Content;
use DOMDocument;
use DOMNode;
use DOMText;
use DOMXPath;
use Exception;
use Friendica\Core\Addon;
use Friendica\Core\Cache;
use Friendica\Core\Config;
use Friendica\Core\L10n;
use Friendica\Core\Renderer;
use Friendica\Core\System;
use Friendica\Database\DBA;
use Friendica\Util\DateTimeFormat;
use Friendica\Util\Network;
use Friendica\Util\ParseUrl;
use Friendica\Util\Proxy as ProxyUtils;
use Friendica\Util\Strings;
/**
* Handles all OEmbed content fetching and replacement
*
* OEmbed is a standard used to allow an embedded representation of a URL on
* third party sites
*
* @see https://oembed.com
*
* @author Hypolite Petovan <hypolite@mrpetovan.com>
*/
class OEmbed
{
public static function replaceCallback($matches)
{
$embedurl = $matches[1];
$j = self::fetchURL($embedurl, !self::isAllowedURL($embedurl));
$s = self::formatObject($j);
return $s;
}
/**
* @brief Get data from an URL to embed its content.
*
* @param string $embedurl The URL from which the data should be fetched.
* @param bool $no_rich_type If set to true rich type content won't be fetched.
*
* @return \Friendica\Object\OEmbed
*/
public static function fetchURL($embedurl, $no_rich_type = false)
{
$embedurl = trim($embedurl, '\'"');
$a = get_app();
$cache_key = 'oembed:' . $a->videowidth . ':' . $embedurl;
$condition = ['url' => Strings::normaliseLink($embedurl), 'maxwidth' => $a->videowidth];
$oembed_record = DBA::selectFirst('oembed', ['content'], $condition);
if (DBA::isResult($oembed_record)) {
$json_string = $oembed_record['content'];
} else {
$json_string = Cache::get($cache_key);
}
// These media files should now be caught in bbcode.php
// left here as a fallback in case this is called from another source
$noexts = ['mp3', 'mp4', 'ogg', 'ogv', 'oga', 'ogm', 'webm'];
$ext = pathinfo(strtolower($embedurl), PATHINFO_EXTENSION);
$oembed = new \Friendica\Object\OEmbed($embedurl);
if ($json_string) {
$oembed->parseJSON($json_string);
} else {
$json_string = '';
if (!in_array($ext, $noexts)) {
// try oembed autodiscovery
$redirects = 0;
$html_text = Network::fetchUrl($embedurl, false, $redirects, 15, 'text/*');
if ($html_text) {
$dom = @DOMDocument::loadHTML($html_text);
if ($dom) {
$xpath = new DOMXPath($dom);
$entries = $xpath->query("//link[@type='application/json+oembed']");
foreach ($entries as $e) {
$href = $e->getAttributeNode('href')->nodeValue;
$json_string = Network::fetchUrl($href . '&maxwidth=' . $a->videowidth);
break;
}
$entries = $xpath->query("//link[@type='text/json+oembed']");
foreach ($entries as $e) {
$href = $e->getAttributeNode('href')->nodeValue;
$json_string = Network::fetchUrl($href . '&maxwidth=' . $a->videowidth);
break;
}
}
}
}
$json_string = trim($json_string);
if (!$json_string || $json_string[0] != '{') {
$json_string = '{"type":"error"}';
}
$oembed->parseJSON($json_string);
if (!empty($oembed->type) && $oembed->type != 'error') {
DBA::insert('oembed', [
'url' => Strings::normaliseLink($embedurl),
'maxwidth' => $a->videowidth,
'content' => $json_string,
'created' => DateTimeFormat::utcNow()
], true);
$cache_ttl = Cache::DAY;
} else {
$cache_ttl = Cache::FIVE_MINUTES;
}
Cache::set($cache_key, $json_string, $cache_ttl);
}
if ($oembed->type == 'error') {
return $oembed;
}
// Always embed the SSL version
$oembed->html = str_replace(['http://www.youtube.com/', 'http://player.vimeo.com/'], ['https://www.youtube.com/', 'https://player.vimeo.com/'], $oembed->html);
// If fetching information doesn't work, then improve via internal functions
if ($no_rich_type && ($oembed->type == 'rich')) {
$data = ParseUrl::getSiteinfoCached($embedurl, true, false);
$oembed->type = $data['type'];
if ($oembed->type == 'photo') {
$oembed->url = $data['url'];
}
if (isset($data['title'])) {
$oembed->title = $data['title'];
}
if (isset($data['text'])) {
$oembed->description = $data['text'];
}
if (!empty($data['images'])) {
$oembed->thumbnail_url = $data['images'][0]['src'];
$oembed->thumbnail_width = $data['images'][0]['width'];
$oembed->thumbnail_height = $data['images'][0]['height'];
}
}
Addon::callHooks('oembed_fetch_url', $embedurl, $oembed);
return $oembed;
}
private static function formatObject(\Friendica\Object\OEmbed $oembed)
{
$ret = '<div class="oembed ' . $oembed->type . '">';
switch ($oembed->type) {
case "video":
if ($oembed->thumbnail_url) {
$tw = (isset($oembed->thumbnail_width) && intval($oembed->thumbnail_width)) ? $oembed->thumbnail_width : 200;
$th = (isset($oembed->thumbnail_height) && intval($oembed->thumbnail_height)) ? $oembed->thumbnail_height : 180;
// make sure we don't attempt divide by zero, fallback is a 1:1 ratio
$tr = (($th) ? $tw / $th : 1);
$th = 120;
$tw = $th * $tr;
$tpl = Renderer::getMarkupTemplate('oembed_video.tpl');
$ret .= Renderer::replaceMacros($tpl, [
'$baseurl' => System::baseUrl(),
'$embedurl' => $oembed->embed_url,
'$escapedhtml' => base64_encode($oembed->html),
'$tw' => $tw,
'$th' => $th,
'$turl' => $oembed->thumbnail_url,
]);
} else {
$ret = $oembed->html;
}
break;
case "photo":
$ret .= '<img width="' . $oembed->width . '" src="' . ProxyUtils::proxifyUrl($oembed->url) . '">';
break;
case "link":
break;
case "rich":
$ret .= ProxyUtils::proxifyHtml($oembed->html);
break;
}
// add link to source if not present in "rich" type
if ($oembed->type != 'rich' || !strpos($oembed->html, $oembed->embed_url)) {
$ret .= '<h4>';
if (!empty($oembed->title)) {
if (!empty($oembed->provider_name)) {
$ret .= $oembed->provider_name . ": ";
}
$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->title . '</a>';
if (!empty($oembed->author_name)) {
$ret .= ' (' . $oembed->author_name . ')';
}
} elseif (!empty($oembed->provider_name) || !empty($oembed->author_name)) {
$embedlink = "";
if (!empty($oembed->provider_name)) {
$embedlink .= $oembed->provider_name;
}
if (!empty($oembed->author_name)) {
if ($embedlink != "") {
$embedlink .= ": ";
}
$embedlink .= $oembed->author_name;
}
if (trim($embedlink) == "") {
$embedlink = $oembed->embed_url;
}
$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $embedlink . '</a>';
} else {
$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->embed_url . '</a>';
}
$ret .= "</h4>";
} elseif (!strpos($oembed->html, $oembed->embed_url)) {
// add <a> for html2bbcode conversion
$ret .= '<a href="' . $oembed->embed_url . '" rel="oembed">' . $oembed->title . '</a>';
}
$ret .= '</div>';
return str_replace("\n", "", $ret);
}
public static function BBCode2HTML($text)
{
$stopoembed = Config::get("system", "no_oembed");
if ($stopoembed == true) {
return preg_replace("/\[embed\](.+?)\[\/embed\]/is", "<!-- oembed $1 --><i>" . L10n::t('Embedding disabled') . " : $1</i><!-- /oembed $1 -->", $text);
}
return preg_replace_callback("/\[embed\](.+?)\[\/embed\]/is", ['self', 'replaceCallback'], $text);
}
/**
* Find <span class='oembed'>..<a href='url' rel='oembed'>..</a></span>
* and replace it with [embed]url[/embed]
*/
public static function HTML2BBCode($text)
{
// start parser only if 'oembed' is in text
if (strpos($text, "oembed")) {
// convert non ascii chars to html entities
$html_text = mb_convert_encoding($text, 'HTML-ENTITIES', mb_detect_encoding($text));
// If it doesn't parse at all, just return the text.
$dom = @DOMDocument::loadHTML($html_text);
if (!$dom) {
return $text;
}
$xpath = new DOMXPath($dom);
$xattr = self::buildXPath("class", "oembed");
$entries = $xpath->query("//div[$xattr]");
$xattr = "@rel='oembed'"; //oe_build_xpath("rel","oembed");
foreach ($entries as $e) {
$href = $xpath->evaluate("a[$xattr]/@href", $e)->item(0)->nodeValue;
if (!is_null($href)) {
$e->parentNode->replaceChild(new DOMText("[embed]" . $href . "[/embed]"), $e);
}
}
return self::getInnerHTML($dom->getElementsByTagName("body")->item(0));
} else {
return $text;
}
}
/**
* Determines if rich content OEmbed is allowed for the provided URL
*
* @brief Determines if rich content OEmbed is allowed for the provided URL
* @param string $url
* @return boolean
*/
public static function isAllowedURL($url)
{
if (!Config::get('system', 'no_oembed_rich_content')) {
return true;
}
$domain = parse_url($url, PHP_URL_HOST);
if (empty($domain)) {
return false;
}
$str_allowed = Config::get('system', 'allowed_oembed', '');
if (empty($str_allowed)) {
return false;
}
$allowed = explode(',', $str_allowed);
return Network::isDomainAllowed($domain, $allowed);
}
public static function getHTML($url, $title = null)
{
// Always embed the SSL version
$url = str_replace(["http://www.youtube.com/", "http://player.vimeo.com/"],
["https://www.youtube.com/", "https://player.vimeo.com/"], $url);
$o = self::fetchURL($url, !self::isAllowedURL($url));
if (!is_object($o) || property_exists($o, 'type') && $o->type == 'error') {
throw new Exception('OEmbed failed for URL: ' . $url);
}
if (!empty($title)) {
$o->title = $title;
}
$html = self::formatObject($o);
return $html;
}
/**
* @brief Generates the iframe HTML for an oembed attachment.
*
* Width and height are given by the remote, and are regularly too small for
* the generated iframe.
*
* The width is entirely discarded for the actual width of the post, while fixed
* height is used as a starting point before the inevitable resizing.
*
* Since the iframe is automatically resized on load, there are no need for ugly
* and impractical scrollbars.
*
* @todo This function is currently unused until someone™ adds support for a separate OEmbed domain
*
* @param string $src Original remote URL to embed
* @param string $width
* @param string $height
* @return string formatted HTML
*
* @see oembed_format_object()
*/
private static function iframe($src, $width, $height)
{
$a = get_app();
if (!$height || strstr($height, '%')) {
$height = '200';
}
$width = '100%';
$src = System::baseUrl() . '/oembed/' . Strings::base64UrlEncode($src);
return '<iframe onload="resizeIframe(this);" class="embed_rich" height="' . $height . '" width="' . $width . '" src="' . $src . '" allowfullscreen scrolling="no" frameborder="no">' . L10n::t('Embedded content') . '</iframe>';
}
/**
* Generates an XPath query to select elements whose provided attribute contains
* the provided value in a space-separated list.
*
* @brief Generates attribute search XPath string
*
* @param string $attr Name of the attribute to seach
* @param string $value Value to search in a space-separated list
* @return string
*/
private static function buildXPath($attr, $value)
{
// https://www.westhoffswelt.de/blog/2009/6/9/select-html-elements-with-more-than-one-css-class-using-xpath
return "contains(normalize-space(@$attr), ' $value ') or substring(normalize-space(@$attr), 1, string-length('$value') + 1) = '$value ' or substring(normalize-space(@$attr), string-length(@$attr) - string-length('$value')) = ' $value' or @$attr = '$value'";
}
/**
* Returns the inner XML string of a provided DOMNode
*
* @brief Returns the inner XML string of a provided DOMNode
*
* @param DOMNode $node
* @return string
*/
private static function getInnerHTML(DOMNode $node)
{
$innerHTML = '';
$children = $node->childNodes;
foreach ($children as $child) {
$innerHTML .= $child->ownerDocument->saveXML($child);
}
return $innerHTML;
}
}