<?php
/*
Copyright (c) 2009-2014 F3::Factory/Bong Cosca, All rights reserved.
This file is part of the Fat-Free Framework (http://fatfree.sf.net).
THE SOFTWARE AND DOCUMENTATION ARE PROVIDED "AS IS" WITHOUT WARRANTY OF
ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
PURPOSE.
Please see the license.txt file for more information.
*/
namespace Web;
//! Pingback 1.0 protocol (client and server) implementation
class Pingback extends \Prefab {
protected
//! Transaction history
$log;
/**
* Return TRUE if URL points to a pingback-enabled resource
* @return bool
* @param $url
**/
protected function enabled($url) {
$web=\Web::instance();
$req=$web->request($url);
$found=FALSE;
if ($req && $req['body']) {
// Look for pingback header
foreach ($req['headers'] as $header)
if (preg_match('/^X-Pingback:\h*(.+)/',$header,$href)) {
$found=$href[1];
break;
}
if (!$found &&
// Scan page for pingback link tag
preg_match('/<link\h+(.+?)\h*\/?>/i',$req['body'],$parts) &&
preg_match('/rel\h*=\h*"pingback"/i',$parts[1]) &&
preg_match('/href\h*=\h*"\h*(.+?)\h*"/i',$parts[1],$href))
$found=$href[1];
}
return $found;
}
/**
* Load local page contents, parse HTML anchor tags, find permalinks,
* and send XML-RPC calls to corresponding pingback servers
* @return NULL
* @param $source string
**/
function inspect($source) {
$fw=\Base::instance();
$web=\Web::instance();
$parts=parse_url($source);
if (empty($parts['scheme']) || empty($parts['host']) ||
$parts['host']==$fw->get('HOST')) {
$req=$web->request($source);
$doc=new \DOMDocument('1.0',$fw->get('ENCODING'));
$doc->stricterrorchecking=FALSE;
$doc->recover=TRUE;
if ($req && @$doc->loadhtml($req['body'])) {
// Parse anchor tags
$links=$doc->getelementsbytagname('a');
foreach ($links as $link) {
$permalink=$link->getattribute('href');
// Find pingback-enabled resources
if ($permalink && $found=$this->enabled($permalink)) {
$req=$web->request($found,
array(
'method'=>'POST',
'header'=>'Content-Type: application/xml',
'content'=>xmlrpc_encode_request(
'pingback.ping',
array($source,$permalink),
array('encoding'=>$fw->get('ENCODING'))
)
)
);
if ($req && $req['body'])
$this->log.=date('r').' '.
$permalink.' [permalink:'.$found.']'.PHP_EOL.
$req['body'].PHP_EOL;
}
}
}
unset($doc);
}
}
/**
* Receive ping, check if local page is pingback-enabled, verify
* source contents, and return XML-RPC response
* @return string
* @param $func callback
* @param $path string
**/
function listen($func,$path=NULL) {
$fw=\Base::instance();
if (PHP_SAPI!='cli') {
header('X-Powered-By: '.$fw->get('PACKAGE'));
header('Content-Type: application/xml; '.
'charset='.$charset=$fw->get('ENCODING'));
}
if (!$path)
$path=$fw->get('BASE');
$web=\Web::instance();
$args=xmlrpc_decode_request($fw->get('BODY'),$method,$charset);
$options=array('encoding'=>$charset);
if ($method=='pingback.ping' && isset($args[0],$args[1])) {
list($source,$permalink)=$args;
$doc=new \DOMDocument('1.0',$fw->get('ENCODING'));
// Check local page if pingback-enabled
$parts=parse_url($permalink);
if ((empty($parts['scheme']) ||
$parts['host']==$fw->get('HOST')) &&
preg_match('/^'.preg_quote($path,'/').'/'.
($fw->get('CASELESS')?'i':''),$parts['path']) &&
$this->enabled($permalink)) {
// Check source
$parts=parse_url($source);
if ((empty($parts['scheme']) ||
$parts['host']==$fw->get('HOST')) &&
($req=$web->request($source)) &&
$doc->loadhtml($req['body'])) {
$links=$doc->getelementsbytagname('a');
foreach ($links as $link) {
if ($link->getattribute('href')==$permalink) {
call_user_func_array($func,
array($source,$req['body']));
// Success
die(xmlrpc_encode_request(NULL,$source,$options));
}
}
// No link to local page
die(xmlrpc_encode_request(NULL,0x11,$options));
}
// Source failure
die(xmlrpc_encode_request(NULL,0x10,$options));
}
// Doesn't exist (or not pingback-enabled)
die(xmlrpc_encode_request(NULL,0x21,$options));
}
// Access denied
die(xmlrpc_encode_request(NULL,0x31,$options));
}
/**
* Return transaction history
* @return string
**/
function log() {
return $this->log;
}
/**
* Instantiate class
* @return object
**/
function __construct() {
// Suppress errors caused by invalid HTML structures
libxml_use_internal_errors(TRUE);
}
}