gnu-social/plugins/Irc/extlib/phergie/Phergie/Plugin/Url.php
2010-07-25 16:04:12 -07:00

639 lines
21 KiB
PHP

<?php
/**
* Phergie
*
* PHP version 5
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.
* It is also available through the world-wide-web at this URL:
* http://phergie.org/license
*
* @category Phergie
* @package Phergie_Plugin_Url
* @author Phergie Development Team <team@phergie.org>
* @copyright 2008-2010 Phergie Development Team (http://phergie.org)
* @license http://phergie.org/license New BSD License
* @link http://pear.phergie.org/package/Phergie_Plugin_Url
*/
/**
* Monitors incoming messages for instances of URLs and responds with messages
* containing relevant information about detected URLs.
*
* Has an utility method accessible via
* $this->getPlugin('Url')->getTitle('http://foo..').
*
* @category Phergie
* @package Phergie_Plugin_Url
* @author Phergie Development Team <team@phergie.org>
* @license http://phergie.org/license New BSD License
* @link http://pear.phergie.org/package/Phergie_Plugin_Url
* @uses Phergie_Plugin_Encoding pear.phergie.org
* @uses Phergie_Plugin_Http pear.phergie.org
* @uses Phergie_Plugin_Tld pear.phergie.org
*/
class Phergie_Plugin_Url extends Phergie_Plugin_Abstract
{
/**
* Links output format
*
* Can use the variables %nick%, %title% and %link% in it to display
* page titles and links
*
* @var string
*/
protected $baseFormat = '%message%';
protected $messageFormat = '[ %link% ] %title%';
/**
* Flag indicating whether a single response should be sent for a single
* message containing multiple links
*
* @var bool
*/
protected $mergeLinks = true;
/**
* Max length of the fetched URL title
*
* @var int
*/
protected $titleLength = 40;
/**
* Url cache to prevent spamming, especially with multiple bots on the
* same channel
*
* @var array
*/
protected $urlCache = array();
protected $shortCache = array();
/**
* Time in seconds to store the cached entries
*
* Setting it to 0 or below disables the cache expiration
*
* @var int
*/
protected $expire = 1800;
/**
* Number of entries to keep in the cache at one time per channel
*
* Setting it to 0 or below disables the cache limit
*
* @var int
*/
protected $limit = 10;
/**
* Flag that determines if the plugin will fall back to using an HTTP
* stream when a URL using SSL is detected and OpenSSL support isn't
* available in the PHP installation in use
*
* @var bool
*/
protected $sslFallback = true;
/**
* Flag that is set to true by the custom error handler if an HTTP error
* code has been received
*
* @var boolean
*/
protected $errorStatus = false;
protected $errorMessage = null;
/**
* Flag indicating whether or not to display error messages as the title
* if a link posted encounters an error
*
* @var boolean
*/
protected $showErrors = true;
/**
* Flag indicating whether to detect schemeless URLS (i.e. "example.com")
*
* @var boolean
*/
protected $detectSchemeless = false;
/**
* Shortener object
*/
protected $shortener;
/**
* Array of renderers
*/
protected $renderers = array();
/**
* Checks for dependencies.
*
* @return void
*/
public function onLoad()
{
$plugins = $this->plugins;
$plugins->getPlugin('Encoding');
$plugins->getPlugin('Http');
$plugins->getPlugin('Tld');
// make the shortener configurable
$shortener = $this->getConfig('url.shortener', 'Trim');
$shortener = "Phergie_Plugin_Url_Shorten_{$shortener}";
$this->shortener = new $shortener($this->plugins->getPlugin('Http'));
if (!$this->shortener instanceof Phergie_Plugin_Url_Shorten_Abstract) {
$this->fail("Declared shortener class {$shortener} is not of proper ancestry");
}
// load config (a bit ugly, but focusing on porting):
foreach (
array(
'detect_schemeless' => 'detectSchemeless',
'base_format' => 'baseFormat',
'message_format' => 'messageFormat',
'merge_links' => 'mergeLinks',
'title_length' => 'titleLength',
'show_errors' => 'showErrors',
'expire' => 'expire',
) as $config => $local) {
if (isset($this->config["url.{$config}"])) {
$this->$local = $this->config["uri.{$config}"];
}
}
}
/**
* Checks an incoming message for the presence of a URL and, if one is
* found, responds with its title if it is an HTML document and the
* shortened equivalent of its original URL if it meets length requirements.
*
* @todo Update this to pull configuration settings from $this->config
* rather than caching them as class properties
* @return void
*/
public function onPrivmsg()
{
$this->handleMsg();
}
/**
* Checks an incoming message for the presence of a URL and, if one is
* found, responds with its title if it is an HTML document and the
* shortened equivalent of its original URL if it meets length requirements.
*
* @todo Update this to pull configuration settings from $this->config
* rather than caching them as class properties
* @return void
*/
public function onAction()
{
$this->handleMsg();
}
/**
* Handles message events and responds with url titles.
*
* @return void
*/
protected function handleMsg()
{
$source = $this->getEvent()->getSource();
$user = $this->getEvent()->getNick();
$responses = array();
$urls = $this->findUrls($this->getEvent()->getArgument(1));
foreach ($urls as $parsed) {
$url = $parsed['glued'];
// allow out-of-class renderers to handle this URL
foreach ($this->renderers as $renderer) {
if ($renderer->renderUrl($parsed) === true) {
// renderers should return true if they've fully
// rendered the passed URL (they're responsible
// for their own output)
$this->debug('Handled by renderer: ' . get_class($renderer));
continue 2;
}
}
// Convert url
$shortenedUrl = $this->shortener->shorten($url);
if (!$shortenedUrl) {
$this->debug('Invalid Url: Unable to shorten. (' . $url . ')');
$shortenedUrl = $url;
}
// Prevent spamfest
if ($this->checkUrlCache($url, $shortenedUrl)) {
$this->debug('Invalid Url: URL is in the cache. (' . $url . ')');
continue;
}
$title = $this->getTitle($url);
if (!empty($title)) {
$responses[] = str_replace(
array(
'%title%',
'%link%',
'%nick%'
), array(
$title,
$shortenedUrl,
$user
), $this->messageFormat
);
}
// Update cache
$this->updateUrlCache($url, $shortenedUrl);
unset($title, $shortenedUrl, $title);
}
// Check to see if there were any URL responses, format them and handle if they
// get merged into one message or not
if (count($responses) > 0) {
if ($this->mergeLinks) {
$message = str_replace(
array(
'%message%',
'%nick%'
), array(
implode('; ', $responses),
$user
), $this->baseFormat
);
$this->doPrivmsg($source, $message);
} else {
foreach ($responses as $response) {
$message = str_replace(
array(
'%message%',
'%nick%'
), array(
implode('; ', $responses),
$user
), $this->baseFormat
);
$this->doPrivmsg($source, $message);
}
}
}
}
/**
* Detect URLs in a given string.
*
* @param string $message the string to detect urls in
*
* @return array the array of urls found
*/
public function findUrls($message)
{
$pattern = '#'.($this->detectSchemeless ? '' : 'https?://').'(?:([0-9]{1,3}(?:\.[0-9]{1,3}){3})(?![^/]) | ('
.($this->detectSchemeless ? '(?<!http:/|https:/)[@/\\\]' : '').')?(?:(?:[a-z0-9_-]+\.?)+\.[a-z0-9]{1,6}))[^\s]*#xis';
$urls = array();
// URL Match
if (preg_match_all($pattern, $message, $matches, PREG_SET_ORDER)) {
foreach ($matches as $m) {
$url = trim(rtrim($m[0], ', ].?!;'));
// Check to see if the URL was from an email address, is a directory, etc
if (!empty($m[2])) {
$this->debug('Invalid Url: URL is either an email or a directory path. (' . $url . ')');
continue;
}
// Parse the given URL
if (!$parsed = $this->parseUrl($url)) {
$this->debug('Invalid Url: Could not parse the URL. (' . $url . ')');
continue;
}
// Check to see if the given IP/Host is valid
if (!empty($m[1]) and !$this->checkValidIP($m[1])) {
$this->debug('Invalid Url: ' . $m[1] . ' is not a valid IP address. (' . $url . ')');
continue;
}
// Process TLD if it's not an IP
if (empty($m[1])) {
// Get the TLD from the host
$pos = strrpos($parsed['host'], '.');
$parsed['tld'] = ($pos !== false ? substr($parsed['host'], ($pos+1)) : '');
// Check to see if the URL has a valid TLD
if ($this->plugins->tld->getTld($parsed['tld']) === false) {
$this->debug('Invalid Url: ' . $parsed['tld'] . ' is not a supported TLD. (' . $url . ')');
continue;
}
}
// Check to see if the URL is to a secured site or not and handle it accordingly
if ($parsed['scheme'] == 'https' && !extension_loaded('openssl')) {
if (!$this->sslFallback) {
$this->debug('Invalid Url: HTTPS is an invalid scheme, OpenSSL isn\'t available. (' . $url . ')');
continue;
} else {
$parsed['scheme'] = 'http';
}
}
if (!in_array($parsed['scheme'], array('http', 'https'))) {
$this->debug('Invalid Url: ' . $parsed['scheme'] . ' is not a supported scheme. (' . $url . ')');
continue;
}
$urls[] = $parsed + array('glued' => $this->glueURL($parsed));
}
}
return $urls;
}
/**
* Checks a given URL (+shortened) against the cache to verify if they were
* previously posted on the channel.
*
* @param string $url The URL to check against
* @param string $shortenedUrl The shortened URL to check against
*
* @return bool
*/
protected function checkUrlCache($url, $shortenedUrl)
{
$source = $this->getEvent()->getSource();
/**
* Transform the URL (+shortened) into a HEX CRC32 checksum to prevent potential problems
* and minimize the size of the cache for less cache bloat.
*/
$url = $this->getUrlChecksum($url);
$shortenedUrl = $this->getUrlChecksum($shortenedUrl);
$cache = array(
'url' => isset($this->urlCache[$source][$url]) ? $this->urlCache[$source][$url] : null,
'shortened' => isset($this->shortCache[$source][$shortenedUrl]) ? $this->shortCache[$source][$shortenedUrl] : null
);
$expire = $this->expire;
$this->debug("Cache expire: {$expire}");
/**
* If cache expiration is enabled, check to see if the given url has expired in the cache
* If expire is disabled, simply check to see if the url is listed
*/
if (($expire > 0 && (($cache['url'] + $expire) > time() || ($cache['shortened'] + $expire) > time()))
|| ($expire <= 0 && (isset($cache['url']) || isset($cache['shortened'])))
) {
unset($cache, $url, $shortenedUrl, $expire);
return true;
}
unset($cache, $url, $shortenedUrl, $expire);
return false;
}
/**
* Updates the cache and adds the given URL (+shortened) to the cache. It
* also handles cleaning the cache of old entries as well.
*
* @param string $url The URL to add to the cache
* @param string $shortenedUrl The shortened to add to the cache
*
* @return bool
*/
protected function updateUrlCache($url, $shortenedUrl)
{
$source = $this->getEvent()->getSource();
/**
* Transform the URL (+shortened) into a HEX CRC32 checksum to prevent potential problems
* and minimize the size of the cache for less cache bloat.
*/
$url = $this->getUrlChecksum($url);
$shortenedUrl = $this->getUrlChecksum($shortenedUrl);
$time = time();
// Handle the URL cache and remove old entries that surpass the limit if enabled
$this->urlCache[$source][$url] = $time;
if ($this->limit > 0 && count($this->urlCache[$source]) > $this->limit) {
asort($this->urlCache[$source], SORT_NUMERIC);
array_shift($this->urlCache[$source]);
}
// Handle the shortened cache and remove old entries that surpass the limit if enabled
$this->shortCache[$source][$shortenedUrl] = $time;
if ($this->limit > 0 && count($this->shortCache[$source]) > $this->limit) {
asort($this->shortCache[$source], SORT_NUMERIC);
array_shift($this->shortCache[$source]);
}
unset($url, $shortenedUrl, $time);
}
/**
* Transliterates a UTF-8 string into corresponding ASCII characters and
* truncates and appends an ellipsis to the string if it exceeds a given
* length.
*
* @param string $str String to decode
* @param int $trim Maximum string length, optional
*
* @return string
*/
protected function decode($str, $trim = null)
{
$out = $this->plugins->encoding->transliterate($str);
if ($trim > 0) {
$out = substr($out, 0, $trim) . (strlen($out) > $trim ? '...' : '');
}
return $out;
}
/**
* Takes a url, parses and cleans the URL without of all the junk
* and then return the hex checksum of the url.
*
* @param string $url url to checksum
*
* @return string the hex checksum of the cleaned url
*/
protected function getUrlChecksum($url)
{
$checksum = strtolower(urldecode($this->glueUrl($url, true)));
$checksum = preg_replace('#\s#', '', $this->plugins->encoding->transliterate($checksum));
return dechex(crc32($checksum));
}
/**
* Parses a given URI and procceses the output to remove redundant
* or missing values.
*
* @param string $url the url to parse
*
* @return array the url components
*/
protected function parseUrl($url)
{
if (is_array($url)) return $url;
$url = trim(ltrim($url, ' /@\\'));
if (!preg_match('&^(?:([a-z][-+.a-z0-9]*):)&xis', $url, $matches)) {
$url = 'http://' . $url;
}
$parsed = parse_url($url);
if (!isset($parsed['scheme'])) {
$parsed['scheme'] = 'http';
}
$parsed['scheme'] = strtolower($parsed['scheme']);
if (isset($parsed['path']) && !isset($parsed['host'])) {
$host = $parsed['path'];
$path = '';
if (strpos($parsed['path'], '/') !== false) {
list($host, $path) = array_pad(explode('/', $parsed['path'], 2), 2, null);
}
$parsed['host'] = $host;
$parsed['path'] = $path;
}
return $parsed;
}
/**
* Parses a given URI and then glues it back together in the proper format.
* If base is set, then it chops off the scheme, user and pass and fragment
* information to return a more unique base URI.
*
* @param string $uri uri to rebuild
* @param string $base set to true to only return the base components
*
* @return string the rebuilt uri
*/
protected function glueUrl($uri, $base = false)
{
$parsed = $uri;
if (!is_array($parsed)) {
$parsed = $this->parseUrl($parsed);
}
if (is_array($parsed)) {
$uri = '';
if (!$base) {
$uri .= (!empty($parsed['scheme']) ? $parsed['scheme'] . ':' .
((strtolower($parsed['scheme']) == 'mailto') ? '' : '//') : '');
$uri .= (!empty($parsed['user']) ? $parsed['user'] .
(!empty($parsed['pass']) ? ':' . $parsed['pass'] : '') . '@' : '');
}
if ($base && !empty($parsed['host'])) {
$parsed['host'] = trim($parsed['host']);
if (substr($parsed['host'], 0, 4) == 'www.') {
$parsed['host'] = substr($parsed['host'], 4);
}
}
$uri .= (!empty($parsed['host']) ? $parsed['host'] : '');
if (!empty($parsed['port'])
&& (($parsed['scheme'] == 'http' && $parsed['port'] == 80)
|| ($parsed['scheme'] == 'https' && $parsed['port'] == 443))
) {
unset($parsed['port']);
}
$uri .= (!empty($parsed['port']) ? ':' . $parsed['port'] : '');
if (!empty($parsed['path']) && (!$base || $base && $parsed['path'] != '/')) {
$uri .= (substr($parsed['path'], 0, 1) == '/') ? $parsed['path'] : ('/' . $parsed['path']);
}
$uri .= (!empty($parsed['query']) ? '?' . $parsed['query'] : '');
if (!$base) {
$uri .= (!empty($parsed['fragment']) ? '#' . $parsed['fragment'] : '');
}
}
return $uri;
}
/**
* Checks the given string to see if its a valid IP4 address
*
* @param string $ip the ip to validate
*
* @return bool
*/
protected function checkValidIP($ip)
{
return long2ip(ip2long($ip)) === $ip;
}
/**
* Returns the title of the given page
*
* @param string $url url to the page
*
* @return string title
*/
public function getTitle($url)
{
$http = $this->plugins->getPlugin('Http');
$options = array(
'timeout' => 3.5,
'user_agent' => 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.12) Gecko/20080201 Firefox/2.0.0.12'
);
$response = $http->head($url, array(), $options);
$header = $response->getHeaders('Content-Type');
if (!preg_match('#^(text/x?html|application/xhtml+xml)(?:;.*)?$#', $header)) {
$title = $header;
} else {
$response = $http->get($url, array(), $options);
$content = $response->getContent();
if (preg_match('#<title[^>]*>(.*?)</title>#is', $content, $match)) {
$title = preg_replace('/[\s\v]+/', ' ', trim($match[1]));
}
}
$encoding = $this->plugins->getPlugin('Encoding');
$title = $encoding->decodeEntities($title);
if (empty($title)) {
if ($response->isError()) {
$title = $response->getCodeAsString();
} else {
$title = 'No Title';
}
}
return $title;
}
/**
* Output a debug message
*
* @param string $msg the message to output
*
* @return void
*/
protected function debug($msg)
{
echo "(DEBUG:Url) $msg\n";
}
/**
* Add a renderer to the stack
*
* @param object $obj the renderer to add
*
* @return void
*/
public function registerRenderer($obj)
{
$this->renderers[spl_object_hash($obj)] = $obj;
}
}