<?php
/**
* Zend Framework (http://framework.zend.com/)
*
* @link http://github.com/zendframework/zf2 for the canonical source repository
* @copyright Copyright (c) 2005-2014 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
namespace Zend\Feed\Reader;
use DOMDocument;
use DOMXPath;
use Zend\Cache\Storage\StorageInterface as CacheStorage;
use Zend\Http as ZendHttp;
use Zend\Stdlib\ErrorHandler;
/**
*/
class Reader
{
/**
* Namespace constants
*/
const NAMESPACE_ATOM_03 = 'http://purl.org/atom/ns#';
const NAMESPACE_ATOM_10 = 'http://www.w3.org/2005/Atom';
const NAMESPACE_RDF = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';
const NAMESPACE_RSS_090 = 'http://my.netscape.com/rdf/simple/0.9/';
const NAMESPACE_RSS_10 = 'http://purl.org/rss/1.0/';
/**
* Feed type constants
*/
const TYPE_ANY = 'any';
const TYPE_ATOM_03 = 'atom-03';
const TYPE_ATOM_10 = 'atom-10';
const TYPE_ATOM_10_ENTRY = 'atom-10-entry';
const TYPE_ATOM_ANY = 'atom';
const TYPE_RSS_090 = 'rss-090';
const TYPE_RSS_091 = 'rss-091';
const TYPE_RSS_091_NETSCAPE = 'rss-091n';
const TYPE_RSS_091_USERLAND = 'rss-091u';
const TYPE_RSS_092 = 'rss-092';
const TYPE_RSS_093 = 'rss-093';
const TYPE_RSS_094 = 'rss-094';
const TYPE_RSS_10 = 'rss-10';
const TYPE_RSS_20 = 'rss-20';
const TYPE_RSS_ANY = 'rss';
/**
* Cache instance
*
* @var CacheStorage
*/
protected static $cache = null;
/**
* HTTP client object to use for retrieving feeds
*
* @var ZendHttp\Client
*/
protected static $httpClient = null;
/**
* Override HTTP PUT and DELETE request methods?
*
* @var bool
*/
protected static $httpMethodOverride = false;
protected static $httpConditionalGet = false;
protected static $extensionManager = null;
protected static $extensions = array(
'feed' => array(
'DublinCore\Feed',
'Atom\Feed'
),
'entry' => array(
'Content\Entry',
'DublinCore\Entry',
'Atom\Entry'
),
'core' => array(
'DublinCore\Feed',
'Atom\Feed',
'Content\Entry',
'DublinCore\Entry',
'Atom\Entry'
)
);
/**
* Get the Feed cache
*
* @return CacheStorage
*/
public static function getCache()
{
return static::$cache;
}
/**
* Set the feed cache
*
* @param CacheStorage $cache
* @return void
*/
public static function setCache(CacheStorage $cache)
{
static::$cache = $cache;
}
/**
* Set the HTTP client instance
*
* Sets the HTTP client object to use for retrieving the feeds.
*
* @param ZendHttp\Client $httpClient
* @return void
*/
public static function setHttpClient(ZendHttp\Client $httpClient)
{
static::$httpClient = $httpClient;
}
/**
* Gets the HTTP client object. If none is set, a new ZendHttp\Client will be used.
*
* @return ZendHttp\Client
*/
public static function getHttpClient()
{
if (!static::$httpClient instanceof ZendHttp\Client) {
static::$httpClient = new ZendHttp\Client();
}
return static::$httpClient;
}
/**
* Toggle using POST instead of PUT and DELETE HTTP methods
*
* Some feed implementations do not accept PUT and DELETE HTTP
* methods, or they can't be used because of proxies or other
* measures. This allows turning on using POST where PUT and
* DELETE would normally be used; in addition, an
* X-Method-Override header will be sent with a value of PUT or
* DELETE as appropriate.
*
* @param bool $override Whether to override PUT and DELETE.
* @return void
*/
public static function setHttpMethodOverride($override = true)
{
static::$httpMethodOverride = $override;
}
/**
* Get the HTTP override state
*
* @return bool
*/
public static function getHttpMethodOverride()
{
return static::$httpMethodOverride;
}
/**
* Set the flag indicating whether or not to use HTTP conditional GET
*
* @param bool $bool
* @return void
*/
public static function useHttpConditionalGet($bool = true)
{
static::$httpConditionalGet = $bool;
}
/**
* Import a feed by providing a URI
*
* @param string $uri The URI to the feed
* @param string $etag OPTIONAL Last received ETag for this resource
* @param string $lastModified OPTIONAL Last-Modified value for this resource
* @return Feed\FeedInterface
* @throws Exception\RuntimeException
*/
public static function import($uri, $etag = null, $lastModified = null)
{
$cache = self::getCache();
$feed = null;
$responseXml = '';
$client = self::getHttpClient();
$client->resetParameters();
$headers = new ZendHttp\Headers();
$client->setHeaders($headers);
$client->setUri($uri);
$cacheId = 'Zend_Feed_Reader_' . md5($uri);
if (static::$httpConditionalGet && $cache) {
$data = $cache->getItem($cacheId);
if ($data) {
if ($etag === null) {
$etag = $cache->getItem($cacheId . '_etag');
}
if ($lastModified === null) {
$lastModified = $cache->getItem($cacheId . '_lastmodified');
}
if ($etag) {
$headers->addHeaderLine('If-None-Match', $etag);
}
if ($lastModified) {
$headers->addHeaderLine('If-Modified-Since', $lastModified);
}
}
$response = $client->send();
if ($response->getStatusCode() !== 200 && $response->getStatusCode() !== 304) {
throw new Exception\RuntimeException('Feed failed to load, got response code ' . $response->getStatusCode());
}
if ($response->getStatusCode() == 304) {
$responseXml = $data;
} else {
$responseXml = $response->getBody();
$cache->setItem($cacheId, $responseXml);
if ($response->getHeaders()->get('ETag')) {
$cache->setItem($cacheId . '_etag', $response->getHeaders()->get('ETag')->getFieldValue());
}
if ($response->getHeaders()->get('Last-Modified')) {
$cache->setItem($cacheId . '_lastmodified', $response->getHeaders()->get('Last-Modified')->getFieldValue());
}
}
return static::importString($responseXml);
} elseif ($cache) {
$data = $cache->getItem($cacheId);
if ($data) {
return static::importString($data);
}
$response = $client->send();
if ((int) $response->getStatusCode() !== 200) {
throw new Exception\RuntimeException('Feed failed to load, got response code ' . $response->getStatusCode());
}
$responseXml = $response->getBody();
$cache->setItem($cacheId, $responseXml);
return static::importString($responseXml);
} else {
$response = $client->send();
if ((int) $response->getStatusCode() !== 200) {
throw new Exception\RuntimeException('Feed failed to load, got response code ' . $response->getStatusCode());
}
$reader = static::importString($response->getBody());
$reader->setOriginalSourceUri($uri);
return $reader;
}
}
/**
* Import a feed from a remote URI
*
* Performs similarly to import(), except it uses the HTTP client passed to
* the method, and does not take into account cached data.
*
* Primary purpose is to make it possible to use the Reader with alternate
* HTTP client implementations.
*
* @param string $uri
* @param Http\Client $client
* @return self
* @throws Exception\RuntimeException if response is not an Http\ResponseInterface
*/
public static function importRemoteFeed($uri, Http\ClientInterface $client)
{
$response = $client->get($uri);
if (!$response instanceof Http\ResponseInterface) {
throw new Exception\RuntimeException(sprintf(
'Did not receive a %s\Http\ResponseInterface from the provided HTTP client; received "%s"',
__NAMESPACE__,
(is_object($response) ? get_class($response) : gettype($response))
));
}
if ((int) $response->getStatusCode() !== 200) {
throw new Exception\RuntimeException('Feed failed to load, got response code ' . $response->getStatusCode());
}
$reader = static::importString($response->getBody());
$reader->setOriginalSourceUri($uri);
return $reader;
}
/**
* Import a feed from a string
*
* @param string $string
* @return Feed\FeedInterface
* @throws Exception\InvalidArgumentException
* @throws Exception\RuntimeException
*/
public static function importString($string)
{
$libxmlErrflag = libxml_use_internal_errors(true);
$oldValue = libxml_disable_entity_loader(true);
$dom = new DOMDocument;
$status = $dom->loadXML(trim($string));
foreach ($dom->childNodes as $child) {
if ($child->nodeType === XML_DOCUMENT_TYPE_NODE) {
throw new Exception\InvalidArgumentException(
'Invalid XML: Detected use of illegal DOCTYPE'
);
}
}
libxml_disable_entity_loader($oldValue);
libxml_use_internal_errors($libxmlErrflag);
if (!$status) {
// Build error message
$error = libxml_get_last_error();
if ($error && $error->message) {
$error->message = trim($error->message);
$errormsg = "DOMDocument cannot parse XML: {$error->message}";
} else {
$errormsg = "DOMDocument cannot parse XML: Please check the XML document's validity";
}
throw new Exception\RuntimeException($errormsg);
}
$type = static::detectType($dom);
static::registerCoreExtensions();
if (substr($type, 0, 3) == 'rss') {
$reader = new Feed\Rss($dom, $type);
} elseif (substr($type, 8, 5) == 'entry') {
$reader = new Entry\Atom($dom->documentElement, 0, self::TYPE_ATOM_10);
} elseif (substr($type, 0, 4) == 'atom') {
$reader = new Feed\Atom($dom, $type);
} else {
throw new Exception\RuntimeException('The URI used does not point to a '
. 'valid Atom, RSS or RDF feed that Zend\Feed\Reader can parse.');
}
return $reader;
}
/**
* Imports a feed from a file located at $filename.
*
* @param string $filename
* @throws Exception\RuntimeException
* @return Feed\FeedInterface
*/
public static function importFile($filename)
{
ErrorHandler::start();
$feed = file_get_contents($filename);
$err = ErrorHandler::stop();
if ($feed === false) {
throw new Exception\RuntimeException("File '{$filename}' could not be loaded", 0, $err);
}
return static::importString($feed);
}
/**
* Find feed links
*
* @param $uri
* @return FeedSet
* @throws Exception\RuntimeException
*/
public static function findFeedLinks($uri)
{
$client = static::getHttpClient();
$client->setUri($uri);
$response = $client->send();
if ($response->getStatusCode() !== 200) {
throw new Exception\RuntimeException("Failed to access $uri, got response code " . $response->getStatusCode());
}
$responseHtml = $response->getBody();
$libxmlErrflag = libxml_use_internal_errors(true);
$oldValue = libxml_disable_entity_loader(true);
$dom = new DOMDocument;
$status = $dom->loadHTML(trim($responseHtml));
libxml_disable_entity_loader($oldValue);
libxml_use_internal_errors($libxmlErrflag);
if (!$status) {
// Build error message
$error = libxml_get_last_error();
if ($error && $error->message) {
$error->message = trim($error->message);
$errormsg = "DOMDocument cannot parse HTML: {$error->message}";
} else {
$errormsg = "DOMDocument cannot parse HTML: Please check the XML document's validity";
}
throw new Exception\RuntimeException($errormsg);
}
$feedSet = new FeedSet;
$links = $dom->getElementsByTagName('link');
$feedSet->addLinks($links, $uri);
return $feedSet;
}
/**
* Detect the feed type of the provided feed
*
* @param Feed\AbstractFeed|DOMDocument|string $feed
* @param bool $specOnly
* @return string
* @throws Exception\InvalidArgumentException
* @throws Exception\RuntimeException
*/
public static function detectType($feed, $specOnly = false)
{
if ($feed instanceof Feed\AbstractFeed) {
$dom = $feed->getDomDocument();
} elseif ($feed instanceof DOMDocument) {
$dom = $feed;
} elseif (is_string($feed) && !empty($feed)) {
ErrorHandler::start(E_NOTICE|E_WARNING);
ini_set('track_errors', 1);
$oldValue = libxml_disable_entity_loader(true);
$dom = new DOMDocument;
$status = $dom->loadXML($feed);
foreach ($dom->childNodes as $child) {
if ($child->nodeType === XML_DOCUMENT_TYPE_NODE) {
throw new Exception\InvalidArgumentException(
'Invalid XML: Detected use of illegal DOCTYPE'
);
}
}
libxml_disable_entity_loader($oldValue);
ini_restore('track_errors');
ErrorHandler::stop();
if (!$status) {
if (!isset($phpErrormsg)) {
if (function_exists('xdebug_is_enabled')) {
$phpErrormsg = '(error message not available, when XDebug is running)';
} else {
$phpErrormsg = '(error message not available)';
}
}
throw new Exception\RuntimeException("DOMDocument cannot parse XML: $phpErrormsg");
}
} else {
throw new Exception\InvalidArgumentException('Invalid object/scalar provided: must'
. ' be of type Zend\Feed\Reader\Feed, DomDocument or string');
}
$xpath = new DOMXPath($dom);
if ($xpath->query('/rss')->length) {
$type = self::TYPE_RSS_ANY;
$version = $xpath->evaluate('string(/rss/@version)');
if (strlen($version) > 0) {
switch ($version) {
case '2.0':
$type = self::TYPE_RSS_20;
break;
case '0.94':
$type = self::TYPE_RSS_094;
break;
case '0.93':
$type = self::TYPE_RSS_093;
break;
case '0.92':
$type = self::TYPE_RSS_092;
break;
case '0.91':
$type = self::TYPE_RSS_091;
break;
}
}
return $type;
}
$xpath->registerNamespace('rdf', self::NAMESPACE_RDF);
if ($xpath->query('/rdf:RDF')->length) {
$xpath->registerNamespace('rss', self::NAMESPACE_RSS_10);
if ($xpath->query('/rdf:RDF/rss:channel')->length
|| $xpath->query('/rdf:RDF/rss:image')->length
|| $xpath->query('/rdf:RDF/rss:item')->length
|| $xpath->query('/rdf:RDF/rss:textinput')->length
) {
return self::TYPE_RSS_10;
}
$xpath->registerNamespace('rss', self::NAMESPACE_RSS_090);
if ($xpath->query('/rdf:RDF/rss:channel')->length
|| $xpath->query('/rdf:RDF/rss:image')->length
|| $xpath->query('/rdf:RDF/rss:item')->length
|| $xpath->query('/rdf:RDF/rss:textinput')->length
) {
return self::TYPE_RSS_090;
}
}
$xpath->registerNamespace('atom', self::NAMESPACE_ATOM_10);
if ($xpath->query('//atom:feed')->length) {
return self::TYPE_ATOM_10;
}
if ($xpath->query('//atom:entry')->length) {
if ($specOnly == true) {
return self::TYPE_ATOM_10;
} else {
return self::TYPE_ATOM_10_ENTRY;
}
}
$xpath->registerNamespace('atom', self::NAMESPACE_ATOM_03);
if ($xpath->query('//atom:feed')->length) {
return self::TYPE_ATOM_03;
}
return self::TYPE_ANY;
}
/**
* Set plugin manager for use with Extensions
*
* @param ExtensionManagerInterface $extensionManager
*/
public static function setExtensionManager(ExtensionManagerInterface $extensionManager)
{
static::$extensionManager = $extensionManager;
}
/**
* Get plugin manager for use with Extensions
*
* @return ExtensionManagerInterface
*/
public static function getExtensionManager()
{
if (!isset(static::$extensionManager)) {
static::setExtensionManager(new ExtensionManager());
}
return static::$extensionManager;
}
/**
* Register an Extension by name
*
* @param string $name
* @return void
* @throws Exception\RuntimeException if unable to resolve Extension class
*/
public static function registerExtension($name)
{
$feedName = $name . '\Feed';
$entryName = $name . '\Entry';
$manager = static::getExtensionManager();
if (static::isRegistered($name)) {
if ($manager->has($feedName) || $manager->has($entryName)) {
return;
}
}
if (!$manager->has($feedName) && !$manager->has($entryName)) {
throw new Exception\RuntimeException('Could not load extension: ' . $name
. ' using Plugin Loader. Check prefix paths are configured and extension exists.');
}
if ($manager->has($feedName)) {
static::$extensions['feed'][] = $feedName;
}
if ($manager->has($entryName)) {
static::$extensions['entry'][] = $entryName;
}
}
/**
* Is a given named Extension registered?
*
* @param string $extensionName
* @return bool
*/
public static function isRegistered($extensionName)
{
$feedName = $extensionName . '\Feed';
$entryName = $extensionName . '\Entry';
if (in_array($feedName, static::$extensions['feed'])
|| in_array($entryName, static::$extensions['entry'])
) {
return true;
}
return false;
}
/**
* Get a list of extensions
*
* @return array
*/
public static function getExtensions()
{
return static::$extensions;
}
/**
* Reset class state to defaults
*
* @return void
*/
public static function reset()
{
static::$cache = null;
static::$httpClient = null;
static::$httpMethodOverride = false;
static::$httpConditionalGet = false;
static::$extensionManager = null;
static::$extensions = array(
'feed' => array(
'DublinCore\Feed',
'Atom\Feed'
),
'entry' => array(
'Content\Entry',
'DublinCore\Entry',
'Atom\Entry'
),
'core' => array(
'DublinCore\Feed',
'Atom\Feed',
'Content\Entry',
'DublinCore\Entry',
'Atom\Entry'
)
);
}
/**
* Register core (default) extensions
*
* @return void
*/
protected static function registerCoreExtensions()
{
static::registerExtension('DublinCore');
static::registerExtension('Content');
static::registerExtension('Atom');
static::registerExtension('Slash');
static::registerExtension('WellFormedWeb');
static::registerExtension('Thread');
static::registerExtension('Podcast');
}
/**
* Utility method to apply array_unique operation to a multidimensional
* array.
*
* @param array
* @return array
*/
public static function arrayUnique(array $array)
{
foreach ($array as &$value) {
$value = serialize($value);
}
$array = array_unique($array);
foreach ($array as &$value) {
$value = unserialize($value);
}
return $array;
}
}