+
+ /**
+ * Stream of subscriptions with the same subscriber
+ *
+ * Useful for showing pages that list subscriptions in reverse
+ * chronological order. Has offset & limit to make paging
+ * easy.
+ *
+ * @param integer $profile_id ID of the subscriber profile
+ * @param integer $offset Offset from latest
+ * @param integer $limit Maximum number to fetch
+ *
+ * @return Subscription stream of subscriptions; use fetch() to iterate
+ */
+ public static function bySubscriber($profile_id, $offset = 0, $limit = PROFILES_PER_PAGE)
+ {
+ // "by subscriber" means it is the list of subscribed users we want
+ $ids = self::getSubscribedIDs($profile_id, $offset, $limit);
+ return Subscription::listFind('subscribed', $ids);
+ }
+
+ /**
+ * Stream of subscriptions with the same subscriber
+ *
+ * Useful for showing pages that list subscriptions in reverse
+ * chronological order. Has offset & limit to make paging
+ * easy.
+ *
+ * @param integer $profile_id ID of the subscribed profile
+ * @param integer $offset Offset from latest
+ * @param integer $limit Maximum number to fetch
+ *
+ * @return Subscription stream of subscriptions; use fetch() to iterate
+ */
+ public static function bySubscribed($profile_id, $offset = 0, $limit = PROFILES_PER_PAGE)
+ {
+ // "by subscribed" means it is the list of subscribers we want
+ $ids = self::getSubscriberIDs($profile_id, $offset, $limit);
+ return Subscription::listFind('subscriber', $ids);
+ }
+
+
+ // The following are helper functions to the subscription lists,
+ // notably the public ones get used in places such as Profile
+ public static function getSubscribedIDs($profile_id, $offset, $limit) {
+ return self::getSubscriptionIDs('subscribed', $profile_id, $offset, $limit);
+ }
+
+ public static function getSubscriberIDs($profile_id, $offset, $limit) {
+ return self::getSubscriptionIDs('subscriber', $profile_id, $offset, $limit);
+ }
+
+ private static function getSubscriptionIDs($get_type, $profile_id, $offset, $limit)
+ {
+ switch ($get_type) {
+ case 'subscribed':
+ $by_type = 'subscriber';
+ break;
+ case 'subscriber':
+ $by_type = 'subscribed';
+ break;
+ default:
+ throw new Exception('Bad type argument to getSubscriptionIDs');
+ }
+
+ $cacheKey = 'subscription:by-'.$by_type.':'.$profile_id;
+
+ $queryoffset = $offset;
+ $querylimit = $limit;
+
+ if ($offset + $limit <= self::CACHE_WINDOW) {
+ // Oh, it seems it should be cached
+ $ids = self::cacheGet($cacheKey);
+ if (is_array($ids)) {
+ return array_slice($ids, $offset, $limit);
+ }
+ // Being here indicates we didn't find anything cached
+ // so we'll have to fill it up simultaneously
+ $queryoffset = 0;
+ $querylimit = self::CACHE_WINDOW;
+ }
+
+ $sub = new Subscription();
+ $sub->$by_type = $profile_id;
+ $sub->selectAdd($get_type);
+ $sub->whereAdd("{$get_type} != {$profile_id}");
+ $sub->orderBy('created DESC');
+ $sub->limit($queryoffset, $querylimit);
+
+ if (!$sub->find()) {
+ return array();
+ }
+
+ $ids = $sub->fetchAll($get_type);
+
+ // If we're simultaneously filling up cache, remember to slice
+ if ($queryoffset === 0 && $querylimit === self::CACHE_WINDOW) {
+ self::cacheSet($cacheKey, $ids);
+ return array_slice($ids, $offset, $limit);
+ }
+
+ return $ids;
+ }
+
+ /**
+ * Flush cached subscriptions when subscription is updated
+ *
+ * Because we cache subscriptions, it's useful to flush them
+ * here.
+ *
+ * @param mixed $dataObject Original version of object
+ *
+ * @return boolean success flag.
+ */
+ function update($dataObject=false)
+ {
+ self::blow('subscription:by-subscriber:'.$this->subscriber);
+ self::blow('subscription:by-subscribed:'.$this->subscribed);
+
+ return parent::update($dataObject);
+ }
+
+ function getURI()
+ {
+ if (!empty($this->uri)) {
+ return $this->uri;
+ } else {
+ return self::newURI($this->subscriber, $this->subscribed, $this->created);
+ }
+ }
+
+ static function newURI($subscriber_id, $subscribed_id, $created)
+ {
+ return TagURI::mint('follow:%d:%d:%s',
+ $subscriber_id,
+ $subscribed_id,
+ common_date_iso8601($created));
+ }