Rss-Bridge/lib/Bridge.php
Pierre Mazière 3dd63ab6fd enable proxy usage for individual bridge
Signed-off-by: Pierre Mazière <pierre.maziere@gmx.com>
2016-08-19 10:19:56 +02:00

388 lines
12 KiB
PHP

<?php
/**
* All bridge logic
* Note : adapter are store in other place
*/
interface BridgeInterface{
public function collectData(array $param);
public function getCacheDuration();
public function loadMetadatas();
public function getName();
public function getURI();
}
abstract class BridgeAbstract implements BridgeInterface{
protected $cache;
protected $items = array();
public $name = "Unnamed bridge";
public $uri = "";
public $description = 'No description provided';
public $maintainer = 'No maintainer';
public $useProxy = false;
public $parameters = array();
/**
* Launch probative exception
*/
protected function returnError($message, $code){
throw new \HttpException($message, $code);
}
protected function returnClientError($message){
$this->returnError($message, 400);
}
protected function returnServerError($message){
$this->returnError($message, 500);
}
/**
* Return datas stored in the bridge
* @return mixed
*/
public function getDatas(){
return $this->items;
}
/**
* Defined datas with parameters depending choose bridge
* Note : you can define a cache before with "setCache"
* @param array $param $_REQUEST, $_GET, $_POST, or array with bridge expected paramters
*/
public function setDatas(array $param){
if( !is_null($this->cache) ){
$this->cache->prepare($param);
$time = $this->cache->getTime();
}
else{
$time = false; // No cache ? No time !
}
if( $time !== false && ( time() - $this->getCacheDuration() < $time ) ){ // Cache file has not expired. Serve it.
$this->items = $this->cache->loadData();
}
else{
$this->collectData($param);
if( !is_null($this->cache) ){ // Cache defined ? We go to refresh is memory :D
$this->cache->saveData($this->getDatas());
}
}
}
/**
* Define default bridge name
*/
public function getName(){
return $this->name;
}
/**
* Define default bridge URI
*/
public function getURI(){
return $this->uri;
}
/**
* Define default duraction for cache
*/
public function getCacheDuration(){
return 3600;
}
/**
* Defined cache object to use
*/
public function setCache(\CacheAbstract $cache){
$this->cache = $cache;
return $this;
}
protected function file_get_html($url, $use_include_path = false, $context=null, $offset = -1, $maxLen=-1, $lowercase = true, $forceTagsClosed=true, $target_charset = DEFAULT_TARGET_CHARSET, $stripRN=true, $defaultBRText=DEFAULT_BR_TEXT, $defaultSpanText=DEFAULT_SPAN_TEXT){
$contextOptions = array(
'http' => array(
'user_agent'=>ini_get('user_agent')
),
);
if(defined('PROXY_URL') && $this->useProxy) {
$contextOptions['http']['proxy'] = PROXY_URL;
$contextOptions['http']['request_fulluri'] = true;
if(is_null($context)){
$context = stream_context_create($contextOptions);
} else {
$prevContext=$context;
if(!stream_context_set_option($context,$contextOptions)){
$context=$prevContext;
};
}
}
return file_get_html($url,$use_include_path,$context,$offset,$maxLen,
$lowercase,$forceTagsClosed,$target_charset,$stripRN,$defaultBRText,
$defaultSpanText);
}
}
/**
* Extension of BridgeAbstract allowing caching of files downloaded over http files.
* This is specially useful for sites from Gawker or Liberation networks, which allow pages excerpts top be viewed together on index, while full pages have to be downloaded
* separately.
* This class mainly provides a get_cached method which will will download the file from its remote location.
* TODO allow file cache invalidation by touching files on access, and removing files/directories which have not been touched since ... a long time
* After all, rss-bridge is not respaw, isn't it ?
*/
abstract class HttpCachingBridgeAbstract extends BridgeAbstract {
/**
* Maintain locally cached versions of pages to download to avoid multiple doiwnloads.
* A file name is generated by replacing all "/" by "_", and the file is saved below this bridge cache
* @param url url to cache
* @return content of file as string
*/
public function get_cached($url) {
$simplified_url = str_replace(["http://", "https://", "?", "&", "="], ["", "", "/", "/", "/"], $url);
// TODO build this from the variable given to Cache
$pageCacheDir = __DIR__ . '/../cache/'."pages/";
$filename = $pageCacheDir.$simplified_url;
if (substr($filename, -1) == '/') {
$filename = $filename."index.html";
}
if(file_exists($filename)) {
// $this->message("loading cached file from ".$filename." for page at url ".$url);
// TODO touch file and its parent, and try to do neighbour deletion
$this->refresh_in_cache($pageCacheDir, $filename);
} else {
// $this->message("we have no local copy of ".$url." Downloading to ".$filename);
$dir = substr($filename, 0, strrpos($filename, '/'));
if(!is_dir($dir)) {
// $this->message("creating directories for ".$dir);
mkdir($dir, 0777, true);
}
$this->download_remote($url, $filename);
}
return file_get_contents($filename);
}
public function get_cached_time($url) {
$simplified_url = str_replace(["http://", "https://", "?", "&", "="], ["", "", "/", "/", "/"], $url);
// TODO build this from the variable given to Cache
$pageCacheDir = __DIR__ . '/../cache/'."pages/";
$filename = $pageCacheDir.$simplified_url;
if (substr($filename, -1) == '/') {
$filename = $filename."index.html";
}
if(!file_exists($filename)) {
$this->get_cached($url);
}
return filectime($filename);
}
private function refresh_in_cache($pageCacheDir, $filename) {
$currentPath = $filename;
while(!$pageCacheDir==$currentPath) {
touch($currentPath);
$currentPath = dirname($currentPath);
}
}
public function download_remote($url , $save_path) {
$f = fopen( $save_path , 'w+');
if($f) {
$handle = fopen($url , "rb");
if($handle) {
while (!feof($handle)) {
$contents = fread($handle, 8192);
if($contents) {
fwrite($f , $contents);
}
}
fclose($handle);
}
fclose($f);
}
}
public function remove_from_cache($url) {
$simplified_url = str_replace(["http://", "https://", "?", "&", "="], ["", "", "/", "/", "/"], $url);
// TODO build this from the variable given to Cache
$pageCacheDir = __DIR__ . '/../cache/'."pages/";
$filename = realpath($pageCacheDir.$simplified_url);
$this->message("removing from cache \"".$filename."\" WELL, NOT REALLY");
// filename is NO GOOD
// unlink($filename);
}
public function message($text) {
$backtrace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 3);
$calling = $backtrace[2];
$message = $calling["file"].":".$calling["line"]
." class ".get_class($this)."->".$calling["function"]
." - ".$text;
error_log($message);
}
}
class Bridge{
static protected $dirBridge;
public function __construct(){
throw new \LogicException('Please use ' . __CLASS__ . '::create for new object.');
}
/**
* Checks if a bridge is an instantiable bridge.
* @param string $nameBridge name of the bridge that you want to use
* @return true if it is an instantiable bridge, false otherwise.
*/
static public function isInstantiable($nameBridge) {
$re = new ReflectionClass($nameBridge);
return $re->IsInstantiable();
}
/**
* Create a new bridge object
* @param string $nameBridge Defined bridge name you want use
* @return Bridge object dedicated
*/
static public function create($nameBridge){
if( !static::isValidNameBridge($nameBridge) ){
throw new \InvalidArgumentException('Name bridge must be at least one uppercase follow or not by alphanumeric or dash characters.');
}
$pathBridge = self::getDir() . $nameBridge . '.php';
if( !file_exists($pathBridge) ){
throw new \Exception('The bridge you looking for does not exist. It should be at path '.$pathBridge);
}
require_once $pathBridge;
if(Bridge::isInstantiable($nameBridge)) {
return new $nameBridge();
} else {
return FALSE;
}
}
static public function setDir($dirBridge){
if( !is_string($dirBridge) ){
throw new \InvalidArgumentException('Dir bridge must be a string.');
}
if( !file_exists($dirBridge) ){
throw new \Exception('Dir bridge does not exist.');
}
self::$dirBridge = $dirBridge;
}
static public function getDir(){
$dirBridge = self::$dirBridge;
if( is_null($dirBridge) ){
throw new \LogicException(__CLASS__ . ' class need to know bridge path !');
}
return $dirBridge;
}
static public function isValidNameBridge($nameBridge){
return preg_match('@^[A-Z][a-zA-Z0-9-]*$@', $nameBridge);
}
/**
* Lists the available bridges.
* @return array List of the bridges
*/
static public function listBridges() {
$pathDirBridge = self::getDir();
$listBridge = array();
$dirFiles = scandir($pathDirBridge);
if( $dirFiles !== false ){
foreach( $dirFiles as $fileName ) {
if( preg_match('@([^.]+)\.php$@U', $fileName, $out) ){
$listBridge[] = $out[1];
}
}
}
return $listBridge;
}
static function isWhitelisted( $whitelist, $name ) {
if(in_array("$name", $whitelist) or in_array("$name.php", $whitelist) or count($whitelist) === 1 and trim($whitelist[0]) === '*')
return TRUE;
else
return FALSE;
}
}
abstract class RssExpander extends HttpCachingBridgeAbstract{
public $name;
public $uri;
public $description;
public function collectExpandableDatas(array $param, $name){
if (empty($name)) {
$this->returnServerError('There is no $name for this RSS expander');
}
// $this->message("Loading from ".$param['url']);
// Notice WE DO NOT use cache here on purpose : we want a fresh view of the RSS stream each time
$rssContent = simplexml_load_file($name) or $this->returnServerError('Could not request '.$name);
// $this->message("loaded RSS from ".$param['url']);
// TODO insert RSS format detection
// we suppose for now, we have some RSS 2.0
$this->collect_RSS_2_0_data($rssContent);
}
protected function collect_RSS_2_0_data($rssContent) {
$rssContent = $rssContent->channel[0];
// $this->message("RSS content is ===========\n".var_export($rssContent, true)."===========");
$this->load_RSS_2_0_feed_data($rssContent);
foreach($rssContent->item as $item) {
// $this->message("parsing item ".var_export($item, true));
$this->items[] = $this->parseRSSItem($item);
}
}
protected function RSS_2_0_time_to_timestamp($item) {
return DateTime::createFromFormat('D, d M Y H:i:s e', $item->pubDate)->getTimestamp();
}
// TODO set title, link, description, language, and so on
protected function load_RSS_2_0_feed_data($rssContent) {
$this->name = trim($rssContent->title);
$this->uri = trim($rssContent->link);
$this->description = trim($rssContent->description);
}
/**
* Method should return, from a source RSS item given by lastRSS, one of our Items objects
* @param $item the input rss item
* @return a RSS-Bridge Item, with (hopefully) the whole content)
*/
abstract protected function parseRSSItem($item);
public function getDescription() {
return $this->description;
}
}