1 files changed, 210 insertions, 0 deletions
diff --git a/lib/pubsubhubbub/Subscriber.php b/lib/pubsubhubbub/Subscriber.php
new file mode 100644
index 000000000..5b980a111
--- /dev/null
+++ b/lib/pubsubhubbub/Subscriber.php
@@ -0,0 +1,210 @@
+<?php
+/**
+ * A PHP client library for pubsubhubbub.
+ *
+ * @link    http://code.google.com/p/pubsubhubbub/
+ *
+ * @author  Josh Fraser | joshfraser.com | [email protected]
+ * @license Apache License 2.0
+ */
+namespace Pubsubhubbub\Subscriber;
+
+use InvalidArgumentException;
+
+class Subscriber
+{
+    /**
+     * Put your google key here.
+     * Required if you want to use the google feed API to lookup RSS feeds.
+     *
+     * @var string
+     */
+    protected $google_key = '';
+
+    /**
+     * @var string
+     */
+    protected $hub_url;
+
+    /**
+     * @var string
+     */
+    protected $callback_url;
+
+    /**
+     * @var string
+     */
+    protected $credentials;
+
+    /**
+     * @var string accepted values are "async" and "sync"
+     */
+    protected $verify = 'async';
+
+    /**
+     * @var string
+     */
+    protected $verify_token;
+
+    /**
+     * @var string
+     */
+    protected $lease_seconds;
+
+    /**
+     * Create a new Subscriber (credentials added for SuperFeedr support).
+     *
+     * @param string $hub_url
+     * @param string $callback_url
+     * @param string $credentials
+     */
+    public function __construct($hub_url, $callback_url, $credentials = false)
+    {
+        if (! isset($hub_url)) {
+            throw new InvalidArgumentException('Please specify a hub url');
+        }
+
+        if (! preg_match('|^https?://|i', $hub_url)) {
+            throw new InvalidArgumentException('The specified hub url does not appear to be valid: ' . $hub_url);
+        }
+
+        if (! isset($callback_url)) {
+            throw new InvalidArgumentException('Please specify a callback');
+        }
+
+        $this->hub_url = $hub_url;
+        $this->callback_url = $callback_url;
+        $this->credentials = $credentials;
+    }
+
+    /**
+     * $use_regexp lets you choose whether to use google AJAX feed api (faster, but cached) or a regexp to read from site.
+     *
+     * @param string   $url
+     * @param callable $http_function
+     *
+     * @return string
+     */
+    public function find_feed($url, $http_function = false)
+    {
+        // using google feed API
+        $url = "http://ajax.googleapis.com/ajax/services/feed/lookup?key={$this->google_key}&v=1.0&q=" . urlencode($url);
+        // fetch the content
+        if ($http_function) {
+            $response = $http_function($url);
+        } else {
+            $response = $this->http($url);
+        }
+
+        $result = json_decode($response, true);
+        $rss_url = $result['responseData']['url'];
+
+        return $rss_url;
+    }
+
+    /**
+     * Subscribe to a topic.
+     *
+     * @param string   $topic_url
+     * @param callable $http_function
+     *
+     * @return mixed
+     */
+    public function subscribe($topic_url, $http_function = false)
+    {
+        return $this->change_subscription('subscribe', $topic_url, $http_function);
+    }
+
+    /**
+     * Unsubscribe from a topic.
+     *
+     * @param string   $topic_url
+     * @param callable $http_function
+     *
+     * @return mixed
+     */
+    public function unsubscribe($topic_url, $http_function = false)
+    {
+        return $this->change_subscription('unsubscribe', $topic_url, $http_function);
+    }
+
+    /**
+     * Helper function since sub/unsub are handled the same way.
+     *
+     * @param string   $mode
+     * @param string   $topic_url
+     * @param callable $http_function
+     *
+     * @return mixed
+     */
+    private function change_subscription($mode, $topic_url, $http_function = false)
+    {
+        if (! isset($topic_url)) {
+            throw new InvalidArgumentException('Please specify a topic url');
+        }
+
+        // lightweight check that we're actually working w/ a valid url
+        if (! preg_match('|^https?://|i', $topic_url)) {
+            throw new InvalidArgumentException('The specified topic url does not appear to be valid: ' . $topic_url);
+        }
+
+        // set the mode subscribe/unsubscribe
+        $post_string = 'hub.mode=' . $mode;
+        $post_string .= '&hub.callback=' . urlencode($this->callback_url);
+        $post_string .= '&hub.verify=' . $this->verify;
+        $post_string .= '&hub.verify_token=' . $this->verify_token;
+        $post_string .= '&hub.lease_seconds=' . $this->lease_seconds;
+
+        // append the topic url parameters
+        $post_string .= '&hub.topic=' . urlencode($topic_url);
+
+        // make the http post request and return true/false
+        // easy to over-write to use your own http function
+        if ($http_function) {
+            return call_user_func_array($http_function, [$this->hub_url, $post_string]);
+        }
+
+        return $this->http($this->hub_url, $post_string);
+    }
+
+    /**
+     * Default http function that uses curl to post to the hub endpoint.
+     *
+     * @param string $url
+     * @param string $post_string
+     *
+     * @return mixed
+     */
+    private function http($url, $post_string)
+    {
+
+        // add any additional curl options here
+        $options = [
+            CURLOPT_URL            => $url,
+            CURLOPT_USERAGENT      => 'PubSubHubbub-Subscriber-PHP/1.0',
+            CURLOPT_RETURNTRANSFER => true,
+        ];
+
+        if ($post_string) {
+            $options[CURLOPT_POST] = true;
+            $options[CURLOPT_POSTFIELDS] = $post_string;
+        }
+
+        if ($this->credentials) {
+            $options[CURLOPT_USERPWD] = $this->credentials;
+        }
+
+        $ch = curl_init();
+        curl_setopt_array($ch, $options);
+
+        $response = curl_exec($ch);
+        $info = curl_getinfo($ch);
+
+        // all good -- anything in the 200 range
+        if (substr($info['http_code'], 0, 1) == '2') {
+            return $response;
+        }
+
+        return false;
+    }
+}