<?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\PubSubHubbub;
use DateInterval;
use DateTime;
use Traversable;
use Zend\Feed\Uri;
use Zend\Http\Request as HttpRequest;
use Zend\Stdlib\ArrayUtils;
class Subscriber
{
/**
* An array of URLs for all Hub Servers to subscribe/unsubscribe.
*
* @var array
*/
protected $hubUrls = array();
/**
* An array of optional parameters to be included in any
* (un)subscribe requests.
*
* @var array
*/
protected $parameters = array();
/**
* The URL of the topic (Rss or Atom feed) which is the subject of
* our current intent to subscribe to/unsubscribe from updates from
* the currently configured Hub Servers.
*
* @var string
*/
protected $topicUrl = '';
/**
* The URL Hub Servers must use when communicating with this Subscriber
*
* @var string
*/
protected $callbackUrl = '';
/**
* The number of seconds for which the subscriber would like to have the
* subscription active. Defaults to null, i.e. not sent, to setup a
* permanent subscription if possible.
*
* @var int
*/
protected $leaseSeconds = null;
/**
* The preferred verification mode (sync or async). By default, this
* Subscriber prefers synchronous verification, but is considered
* desirable to support asynchronous verification if possible.
*
* Zend\Feed\Pubsubhubbub\Subscriber will always send both modes, whose
* order of occurrence in the parameter list determines this preference.
*
* @var string
*/
protected $preferredVerificationMode = PubSubHubbub::VERIFICATION_MODE_SYNC;
/**
* An array of any errors including keys for 'response', 'hubUrl'.
* The response is the actual Zend\Http\Response object.
*
* @var array
*/
protected $errors = array();
/**
* An array of Hub Server URLs for Hubs operating at this time in
* asynchronous verification mode.
*
* @var array
*/
protected $asyncHubs = array();
/**
* An instance of Zend\Feed\Pubsubhubbub\Model\SubscriptionPersistence used to background
* save any verification tokens associated with a subscription or other.
*
* @var \Zend\Feed\PubSubHubbub\Model\SubscriptionPersistenceInterface
*/
protected $storage = null;
/**
* An array of authentication credentials for HTTP Basic Authentication
* if required by specific Hubs. The array is indexed by Hub Endpoint URI
* and the value is a simple array of the username and password to apply.
*
* @var array
*/
protected $authentications = array();
/**
* Tells the Subscriber to append any subscription identifier to the path
* of the base Callback URL. E.g. an identifier "subkey1" would be added
* to the callback URL "http://www.example.com/callback" to create a subscription
* specific Callback URL of "http://www.example.com/callback/subkey1".
*
* This is required for all Hubs using the Pubsubhubbub 0.1 Specification.
* It should be manually intercepted and passed to the Callback class using
* Zend\Feed\Pubsubhubbub\Subscriber\Callback::setSubscriptionKey(). Will
* require a route in the form "callback/:subkey" to allow the parameter be
* retrieved from an action using the Zend\Controller\Action::\getParam()
* method.
*
* @var string
*/
protected $usePathParameter = false;
/**
* Constructor; accepts an array or Traversable instance to preset
* options for the Subscriber without calling all supported setter
* methods in turn.
*
* @param array|Traversable $options
*/
public function __construct($options = null)
{
if ($options !== null) {
$this->setOptions($options);
}
}
/**
* Process any injected configuration options
*
* @param array|Traversable $options
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function setOptions($options)
{
if ($options instanceof Traversable) {
$options = ArrayUtils::iteratorToArray($options);
}
if (!is_array($options)) {
throw new Exception\InvalidArgumentException('Array or Traversable object'
. 'expected, got ' . gettype($options));
}
if (array_key_exists('hubUrls', $options)) {
$this->addHubUrls($options['hubUrls']);
}
if (array_key_exists('callbackUrl', $options)) {
$this->setCallbackUrl($options['callbackUrl']);
}
if (array_key_exists('topicUrl', $options)) {
$this->setTopicUrl($options['topicUrl']);
}
if (array_key_exists('storage', $options)) {
$this->setStorage($options['storage']);
}
if (array_key_exists('leaseSeconds', $options)) {
$this->setLeaseSeconds($options['leaseSeconds']);
}
if (array_key_exists('parameters', $options)) {
$this->setParameters($options['parameters']);
}
if (array_key_exists('authentications', $options)) {
$this->addAuthentications($options['authentications']);
}
if (array_key_exists('usePathParameter', $options)) {
$this->usePathParameter($options['usePathParameter']);
}
if (array_key_exists('preferredVerificationMode', $options)) {
$this->setPreferredVerificationMode(
$options['preferredVerificationMode']
);
}
return $this;
}
/**
* Set the topic URL (RSS or Atom feed) to which the intended (un)subscribe
* event will relate
*
* @param string $url
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function setTopicUrl($url)
{
if (empty($url) || !is_string($url) || !Uri::factory($url)->isValid()) {
throw new Exception\InvalidArgumentException('Invalid parameter "url"'
.' of "' . $url . '" must be a non-empty string and a valid'
.' URL');
}
$this->topicUrl = $url;
return $this;
}
/**
* Set the topic URL (RSS or Atom feed) to which the intended (un)subscribe
* event will relate
*
* @return string
* @throws Exception\RuntimeException
*/
public function getTopicUrl()
{
if (empty($this->topicUrl)) {
throw new Exception\RuntimeException('A valid Topic (RSS or Atom'
. ' feed) URL MUST be set before attempting any operation');
}
return $this->topicUrl;
}
/**
* Set the number of seconds for which any subscription will remain valid
*
* @param int $seconds
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function setLeaseSeconds($seconds)
{
$seconds = intval($seconds);
if ($seconds <= 0) {
throw new Exception\InvalidArgumentException('Expected lease seconds'
. ' must be an integer greater than zero');
}
$this->leaseSeconds = $seconds;
return $this;
}
/**
* Get the number of lease seconds on subscriptions
*
* @return int
*/
public function getLeaseSeconds()
{
return $this->leaseSeconds;
}
/**
* Set the callback URL to be used by Hub Servers when communicating with
* this Subscriber
*
* @param string $url
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function setCallbackUrl($url)
{
if (empty($url) || !is_string($url) || !Uri::factory($url)->isValid()) {
throw new Exception\InvalidArgumentException('Invalid parameter "url"'
. ' of "' . $url . '" must be a non-empty string and a valid'
. ' URL');
}
$this->callbackUrl = $url;
return $this;
}
/**
* Get the callback URL to be used by Hub Servers when communicating with
* this Subscriber
*
* @return string
* @throws Exception\RuntimeException
*/
public function getCallbackUrl()
{
if (empty($this->callbackUrl)) {
throw new Exception\RuntimeException('A valid Callback URL MUST be'
. ' set before attempting any operation');
}
return $this->callbackUrl;
}
/**
* Set preferred verification mode (sync or async). By default, this
* Subscriber prefers synchronous verification, but does support
* asynchronous if that's the Hub Server's utilised mode.
*
* Zend\Feed\Pubsubhubbub\Subscriber will always send both modes, whose
* order of occurrence in the parameter list determines this preference.
*
* @param string $mode Should be 'sync' or 'async'
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function setPreferredVerificationMode($mode)
{
if ($mode !== PubSubHubbub::VERIFICATION_MODE_SYNC
&& $mode !== PubSubHubbub::VERIFICATION_MODE_ASYNC
) {
throw new Exception\InvalidArgumentException('Invalid preferred'
. ' mode specified: "' . $mode . '" but should be one of'
. ' Zend\Feed\Pubsubhubbub::VERIFICATION_MODE_SYNC or'
. ' Zend\Feed\Pubsubhubbub::VERIFICATION_MODE_ASYNC');
}
$this->preferredVerificationMode = $mode;
return $this;
}
/**
* Get preferred verification mode (sync or async).
*
* @return string
*/
public function getPreferredVerificationMode()
{
return $this->preferredVerificationMode;
}
/**
* Add a Hub Server URL supported by Publisher
*
* @param string $url
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function addHubUrl($url)
{
if (empty($url) || !is_string($url) || !Uri::factory($url)->isValid()) {
throw new Exception\InvalidArgumentException('Invalid parameter "url"'
. ' of "' . $url . '" must be a non-empty string and a valid'
. ' URL');
}
$this->hubUrls[] = $url;
return $this;
}
/**
* Add an array of Hub Server URLs supported by Publisher
*
* @param array $urls
* @return Subscriber
*/
public function addHubUrls(array $urls)
{
foreach ($urls as $url) {
$this->addHubUrl($url);
}
return $this;
}
/**
* Remove a Hub Server URL
*
* @param string $url
* @return Subscriber
*/
public function removeHubUrl($url)
{
if (!in_array($url, $this->getHubUrls())) {
return $this;
}
$key = array_search($url, $this->hubUrls);
unset($this->hubUrls[$key]);
return $this;
}
/**
* Return an array of unique Hub Server URLs currently available
*
* @return array
*/
public function getHubUrls()
{
$this->hubUrls = array_unique($this->hubUrls);
return $this->hubUrls;
}
/**
* Add authentication credentials for a given URL
*
* @param string $url
* @param array $authentication
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function addAuthentication($url, array $authentication)
{
if (empty($url) || !is_string($url) || !Uri::factory($url)->isValid()) {
throw new Exception\InvalidArgumentException('Invalid parameter "url"'
. ' of "' . $url . '" must be a non-empty string and a valid'
. ' URL');
}
$this->authentications[$url] = $authentication;
return $this;
}
/**
* Add authentication credentials for hub URLs
*
* @param array $authentications
* @return Subscriber
*/
public function addAuthentications(array $authentications)
{
foreach ($authentications as $url => $authentication) {
$this->addAuthentication($url, $authentication);
}
return $this;
}
/**
* Get all hub URL authentication credentials
*
* @return array
*/
public function getAuthentications()
{
return $this->authentications;
}
/**
* Set flag indicating whether or not to use a path parameter
*
* @param bool $bool
* @return Subscriber
*/
public function usePathParameter($bool = true)
{
$this->usePathParameter = $bool;
return $this;
}
/**
* Add an optional parameter to the (un)subscribe requests
*
* @param string $name
* @param string|null $value
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function setParameter($name, $value = null)
{
if (is_array($name)) {
$this->setParameters($name);
return $this;
}
if (empty($name) || !is_string($name)) {
throw new Exception\InvalidArgumentException('Invalid parameter "name"'
. ' of "' . $name . '" must be a non-empty string');
}
if ($value === null) {
$this->removeParameter($name);
return $this;
}
if (empty($value) || (!is_string($value) && $value !== null)) {
throw new Exception\InvalidArgumentException('Invalid parameter "value"'
. ' of "' . $value . '" must be a non-empty string');
}
$this->parameters[$name] = $value;
return $this;
}
/**
* Add an optional parameter to the (un)subscribe requests
*
* @param array $parameters
* @return Subscriber
*/
public function setParameters(array $parameters)
{
foreach ($parameters as $name => $value) {
$this->setParameter($name, $value);
}
return $this;
}
/**
* Remove an optional parameter for the (un)subscribe requests
*
* @param string $name
* @return Subscriber
* @throws Exception\InvalidArgumentException
*/
public function removeParameter($name)
{
if (empty($name) || !is_string($name)) {
throw new Exception\InvalidArgumentException('Invalid parameter "name"'
. ' of "' . $name . '" must be a non-empty string');
}
if (array_key_exists($name, $this->parameters)) {
unset($this->parameters[$name]);
}
return $this;
}
/**
* Return an array of optional parameters for (un)subscribe requests
*
* @return array
*/
public function getParameters()
{
return $this->parameters;
}
/**
* Sets an instance of Zend\Feed\Pubsubhubbub\Model\SubscriptionPersistence used to background
* save any verification tokens associated with a subscription or other.
*
* @param Model\SubscriptionPersistenceInterface $storage
* @return Subscriber
*/
public function setStorage(Model\SubscriptionPersistenceInterface $storage)
{
$this->storage = $storage;
return $this;
}
/**
* Gets an instance of Zend\Feed\Pubsubhubbub\Storage\StoragePersistence used
* to background save any verification tokens associated with a subscription
* or other.
*
* @return Model\SubscriptionPersistenceInterface
* @throws Exception\RuntimeException
*/
public function getStorage()
{
if ($this->storage === null) {
throw new Exception\RuntimeException('No storage vehicle '
. 'has been set.');
}
return $this->storage;
}
/**
* Subscribe to one or more Hub Servers using the stored Hub URLs
* for the given Topic URL (RSS or Atom feed)
*
* @return void
*/
public function subscribeAll()
{
$this->_doRequest('subscribe');
}
/**
* Unsubscribe from one or more Hub Servers using the stored Hub URLs
* for the given Topic URL (RSS or Atom feed)
*
* @return void
*/
public function unsubscribeAll()
{
$this->_doRequest('unsubscribe');
}
/**
* Returns a boolean indicator of whether the notifications to Hub
* Servers were ALL successful. If even one failed, FALSE is returned.
*
* @return bool
*/
public function isSuccess()
{
if (count($this->errors) > 0) {
return false;
}
return true;
}
/**
* Return an array of errors met from any failures, including keys:
* 'response' => the Zend\Http\Response object from the failure
* 'hubUrl' => the URL of the Hub Server whose notification failed
*
* @return array
*/
public function getErrors()
{
return $this->errors;
}
/**
* Return an array of Hub Server URLs who returned a response indicating
* operation in Asynchronous Verification Mode, i.e. they will not confirm
* any (un)subscription immediately but at a later time (Hubs may be
* doing this as a batch process when load balancing)
*
* @return array
*/
public function getAsyncHubs()
{
return $this->asyncHubs;
}
/**
* Executes an (un)subscribe request
*
* @param string $mode
* @return void
* @throws Exception\RuntimeException
*/
protected function _doRequest($mode)
{
$client = $this->_getHttpClient();
$hubs = $this->getHubUrls();
if (empty($hubs)) {
throw new Exception\RuntimeException('No Hub Server URLs'
. ' have been set so no subscriptions can be attempted');
}
$this->errors = array();
$this->asyncHubs = array();
foreach ($hubs as $url) {
if (array_key_exists($url, $this->authentications)) {
$auth = $this->authentications[$url];
$client->setAuth($auth[0], $auth[1]);
}
$client->setUri($url);
$client->setRawBody($params = $this->_getRequestParameters($url, $mode));
$response = $client->send();
if ($response->getStatusCode() !== 204
&& $response->getStatusCode() !== 202
) {
$this->errors[] = array(
'response' => $response,
'hubUrl' => $url,
);
/**
* At first I thought it was needed, but the backend storage will
* allow tracking async without any user interference. It's left
* here in case the user is interested in knowing what Hubs
* are using async verification modes so they may update Models and
* move these to asynchronous processes.
*/
} elseif ($response->getStatusCode() == 202) {
$this->asyncHubs[] = array(
'response' => $response,
'hubUrl' => $url,
);
}
}
}
/**
* Get a basic prepared HTTP client for use
*
* @return \Zend\Http\Client
*/
protected function _getHttpClient()
{
$client = PubSubHubbub::getHttpClient();
$client->setMethod(HttpRequest::METHOD_POST);
$client->setOptions(array('useragent' => 'Zend_Feed_Pubsubhubbub_Subscriber/'
. Version::VERSION));
return $client;
}
/**
* Return a list of standard protocol/optional parameters for addition to
* client's POST body that are specific to the current Hub Server URL
*
* @param string $hubUrl
* @param string $mode
* @return string
* @throws Exception\InvalidArgumentException
*/
protected function _getRequestParameters($hubUrl, $mode)
{
if (!in_array($mode, array('subscribe', 'unsubscribe'))) {
throw new Exception\InvalidArgumentException('Invalid mode specified: "'
. $mode . '" which should have been "subscribe" or "unsubscribe"');
}
$params = array(
'hub.mode' => $mode,
'hub.topic' => $this->getTopicUrl(),
);
if ($this->getPreferredVerificationMode()
== PubSubHubbub::VERIFICATION_MODE_SYNC
) {
$vmodes = array(
PubSubHubbub::VERIFICATION_MODE_SYNC,
PubSubHubbub::VERIFICATION_MODE_ASYNC,
);
} else {
$vmodes = array(
PubSubHubbub::VERIFICATION_MODE_ASYNC,
PubSubHubbub::VERIFICATION_MODE_SYNC,
);
}
$params['hub.verify'] = array();
foreach ($vmodes as $vmode) {
$params['hub.verify'][] = $vmode;
}
/**
* Establish a persistent verify_token and attach key to callback
* URL's path/query_string
*/
$key = $this->_generateSubscriptionKey($params, $hubUrl);
$token = $this->_generateVerifyToken();
$params['hub.verify_token'] = $token;
// Note: query string only usable with PuSH 0.2 Hubs
if (!$this->usePathParameter) {
$params['hub.callback'] = $this->getCallbackUrl()
. '?xhub.subscription=' . PubSubHubbub::urlencode($key);
} else {
$params['hub.callback'] = rtrim($this->getCallbackUrl(), '/')
. '/' . PubSubHubbub::urlencode($key);
}
if ($mode == 'subscribe' && $this->getLeaseSeconds() !== null) {
$params['hub.lease_seconds'] = $this->getLeaseSeconds();
}
// hub.secret not currently supported
$optParams = $this->getParameters();
foreach ($optParams as $name => $value) {
$params[$name] = $value;
}
// store subscription to storage
$now = new DateTime();
$expires = null;
if (isset($params['hub.lease_seconds'])) {
$expires = $now->add(new DateInterval('PT' . $params['hub.lease_seconds'] . 'S'))
->format('Y-m-d H:i:s');
}
$data = array(
'id' => $key,
'topic_url' => $params['hub.topic'],
'hub_url' => $hubUrl,
'created_time' => $now->format('Y-m-d H:i:s'),
'lease_seconds' => $params['hub.lease_seconds'],
'verify_token' => hash('sha256', $params['hub.verify_token']),
'secret' => null,
'expiration_time' => $expires,
'subscription_state' => ($mode == 'unsubscribe')? PubSubHubbub::SUBSCRIPTION_TODELETE : PubSubHubbub::SUBSCRIPTION_NOTVERIFIED,
);
$this->getStorage()->setSubscription($data);
return $this->_toByteValueOrderedString(
$this->_urlEncode($params)
);
}
/**
* Simple helper to generate a verification token used in (un)subscribe
* requests to a Hub Server. Follows no particular method, which means
* it might be improved/changed in future.
*
* @return string
*/
protected function _generateVerifyToken()
{
if (!empty($this->testStaticToken)) {
return $this->testStaticToken;
}
return uniqid(rand(), true) . time();
}
/**
* Simple helper to generate a verification token used in (un)subscribe
* requests to a Hub Server.
*
* @param array $params
* @param string $hubUrl The Hub Server URL for which this token will apply
* @return string
*/
protected function _generateSubscriptionKey(array $params, $hubUrl)
{
$keyBase = $params['hub.topic'] . $hubUrl;
$key = md5($keyBase);
return $key;
}
/**
* URL Encode an array of parameters
*
* @param array $params
* @return array
*/
protected function _urlEncode(array $params)
{
$encoded = array();
foreach ($params as $key => $value) {
if (is_array($value)) {
$ekey = PubSubHubbub::urlencode($key);
$encoded[$ekey] = array();
foreach ($value as $duplicateKey) {
$encoded[$ekey][]
= PubSubHubbub::urlencode($duplicateKey);
}
} else {
$encoded[PubSubHubbub::urlencode($key)]
= PubSubHubbub::urlencode($value);
}
}
return $encoded;
}
/**
* Order outgoing parameters
*
* @param array $params
* @return array
*/
protected function _toByteValueOrderedString(array $params)
{
$return = array();
uksort($params, 'strnatcmp');
foreach ($params as $key => $value) {
if (is_array($value)) {
foreach ($value as $keyduplicate) {
$return[] = $key . '=' . $keyduplicate;
}
} else {
$return[] = $key . '=' . $value;
}
}
return implode('&', $return);
}
/**
* This is STRICTLY for testing purposes only...
*/
protected $testStaticToken = null;
final public function setTestStaticToken($token)
{
$this->testStaticToken = (string) $token;
}
}