gnu-social/plugins/Irc/extlib/phergie/Phergie/Plugin/Url.php
2010-06-30 09:33:29 -07:00

694 lines
23 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_Http 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;
/**
* List of error messages to return when the requested URL returns an
* HTTP error
*
* @var array
*/
protected $httpErrors = array(
100 => '100 Continue',
200 => '200 OK',
201 => '201 Created',
204 => '204 No Content',
206 => '206 Partial Content',
300 => '300 Multiple Choices',
301 => '301 Moved Permanently',
302 => '302 Found',
303 => '303 See Other',
304 => '304 Not Modified',
307 => '307 Temporary Redirect',
400 => '400 Bad Request',
401 => '401 Unauthorized',
403 => '403 Forbidden',
404 => '404 Not Found',
405 => '405 Method Not Allowed',
406 => '406 Not Acceptable',
408 => '408 Request Timeout',
410 => '410 Gone',
413 => '413 Request Entity Too Large',
414 => '414 Request URI Too Long',
415 => '415 Unsupported Media Type',
416 => '416 Requested Range Not Satisfiable',
417 => '417 Expectation Failed',
500 => '500 Internal Server Error',
501 => '501 Method Not Implemented',
503 => '503 Service Unavailable',
506 => '506 Variant Also Negotiates'
);
/**
* An array containing a list of TLDs used for non-scheme matches
*
* @var array
*/
protected $tldList = array();
/**
* Shortener object
*/
protected $shortener;
/**
* Array of renderers
*/
protected $renderers = array();
/**
* Initializes settings, checks dependencies.
*
* @return void
*/
public function onConnect()
{
// 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");
}
// Get a list of valid TLDs
if (!is_array($this->tldList) || count($this->tldList) <= 6) {
$tldPath = dirname(__FILE__) . '/Url/url.tld.txt';
$this->tldList = explode("\n", file_get_contents($tldPath));
$this->debug('Loaded ' . count($this->tldList) . ' tlds');
rsort($this->tldList);
}
// 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()
{
$source = $this->getEvent()->getSource();
$user = $this->getEvent()->getNick();
$pattern = '#'.($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';
// URL Match
if (preg_match_all($pattern, $this->getEvent()->getArgument(1), $matches, PREG_SET_ORDER)) {
$responses = array();
foreach ($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. (' . $url . ')');
continue;
}
// allow out-of-class renderers to handle this URL
foreach ($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;
}
}
// 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 (is_array($this->tldList) && !in_array(strtolower($parsed['tld']), $this->tldList)) {
$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;
}
$url = $this->glueURL($parsed);
unset($parsed);
// Convert url
$shortenedUrl = $this->shortener->shorten($url);
if (!$shortenedUrl) {
$this->debug('Invalid Url: Unable to shorten. (' . $url . ')');
continue;
}
// Prevent spamfest
if ($this->checkUrlCache($url, $shortenedUrl)) {
$this->debug('Invalid Url: URL is in the cache. (' . $url . ')');
continue;
}
$title = self::getTitle($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);
}
}
}
}
}
/**
* 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 = $this->decodeTranslit($str);
if ($trim > 0) {
$out = substr($out, 0, $trim) . (strlen($out) > $trim ? '...' : '');
}
return $out;
}
/**
* Custom error handler meant to handle 404 errors and such
*
* @param int $errno the error code
* @param string $errstr the error string
* @param string $errfile file the error occured in
* @param int $errline line the error occured on
*
* @return bool
*/
public function onPhpError($errno, $errstr, $errfile, $errline)
{
if ($errno === E_WARNING) {
// Check to see if there was HTTP warning while connecting to the site
if (preg_match('{HTTP/1\.[01] ([0-9]{3})}i', $errstr, $m)) {
$this->errorStatus = $m[1];
$this->errorMessage = (isset($this->httpErrors[$m[1]]) ? $this->httpErrors[$m[1]] : $m[1]);
$this->debug('PHP Warning: ' . $errstr . 'in ' . $errfile . ' on line ' . $errline);
return true;
}
// Safely ignore these SSL warnings so they don't appear in the log
if (stripos($errstr, 'SSL: fatal protocol error in') !== false
|| stripos($errstr, 'failed to open stream') !== false
|| stripos($errstr, 'HTTP request failed') !== false
|| stripos($errstr, 'SSL: An existing connection was forcibly closed by the remote host') !== false
|| stripos($errstr, 'Failed to enable crypto in') !== false
|| stripos($errstr, 'SSL: An established connection was aborted by the software in your host machine') !== false
|| stripos($errstr, 'SSL operation failed with code') !== false
|| stripos($errstr, 'unable to connect to') !== false
) {
$this->errorStatus = true;
$this->debug('PHP Warning: ' . $errstr . 'in ' . $errfile . ' on line ' . $errline);
return true;
}
}
return false;
}
/**
* 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#', '', $this->decodeTranslit($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 = $http->get($url, array(), $options);
$header = $response->getHeaders('Content-Type');
if (!preg_match('#^(text/x?html|application/xhtml+xml)(?:;.*)?$#', $header)) {
$title = $header;
}
$content = $response->getContent();
if (empty($title)) {
if (preg_match('#<title[^>]*>(.*?)</title>#is', $content, $match)) {
$title = html_entity_decode(trim($match[1]));
}
}
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";
}
/**
* Placeholder/porting helper. Has no function.
*
* @param string $str a string to return
*
* @return string
*/
protected function decodeTranslit($str)
{
// placeholder/porting helper
return $str;
}
/**
* Add a renderer to the stack
*
* @param object $obj the renderer to add
*
* @return void
*/
public function registerRenderer($obj)
{
$this->renderers[] = $obj;
array_unique($this->renderers);
}
}