From d0ea138888cbc5de30f2c9a52a771921efa9fdc1 Mon Sep 17 00:00:00 2001
From: Evan Prodromou <evan@status.net>
Date: Sat, 11 Dec 2010 11:00:04 -0500
Subject: [PATCH] cache stream of subscriptions

---
 classes/Subscription.php | 91 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 89 insertions(+), 2 deletions(-)

diff --git a/classes/Subscription.php b/classes/Subscription.php
index a4764e9f15..763e3835b8 100644
--- a/classes/Subscription.php
+++ b/classes/Subscription.php
@@ -26,6 +26,8 @@ require_once INSTALLDIR.'/classes/Memcached_DataObject.php';
 
 class Subscription extends Memcached_DataObject
 {
+    const CACHE_WINDOW = 201;
+
     ###START_AUTOCODE
     /* the code below is auto generated do not remove the above tag */
 
@@ -91,6 +93,9 @@ class Subscription extends Memcached_DataObject
 
             self::blow('user:notices_with_friends:%d', $subscriber->id);
 
+            self::blow('subscription:by-subscriber:'.$subscriber->id);
+            self::blow('subscription:by-subscribed:'.$other->id);
+
             $subscriber->blowSubscriptionCount();
             $other->blowSubscriberCount();
 
@@ -220,6 +225,9 @@ class Subscription extends Memcached_DataObject
 
             self::blow('user:notices_with_friends:%d', $subscriber->id);
 
+            self::blow('subscription:by-subscriber:'.$subscriber->id);
+            self::blow('subscription:by-subscribed:'.$other->id);
+
             $subscriber->blowSubscriptionCount();
             $other->blowSubscriberCount();
 
@@ -282,6 +290,29 @@ class Subscription extends Memcached_DataObject
     static function bySubscriber($subscriberId,
                                  $offset = 0,
                                  $limit = PROFILES_PER_PAGE)
+    {
+        if ($offset + $limit > self::CACHE_WINDOW) {
+            return new ArrayWrapper(self::realBySubscriber($subscriberId,
+                                                           $offset,
+                                                           $limit));
+        } else {
+            $key = 'subscription:by-subscriber:'.$subscriberId;
+            $window = self::cacheGet($key);
+            if ($window === false) {
+                $window = self::realBySubscriber($subscriberId,
+                                                 0,
+                                                 self::CACHE_WINDOW);
+                self::cacheSet($key, $window);
+            }
+            return new ArrayWrapper(array_slice($window,
+                                                $offset,
+                                                $limit));
+        }
+    }
+
+    private static function realBySubscriber($subscriberId,
+                                             $offset,
+                                             $limit)
     {
         $sub = new Subscription();
 
@@ -294,7 +325,13 @@ class Subscription extends Memcached_DataObject
 
         $sub->find();
 
-        return $sub;
+        $subs = array();
+
+        while ($sub->fetch()) {
+            $subs[] = clone($sub);
+        }
+
+        return $subs;
     }
 
     /**
@@ -314,6 +351,29 @@ class Subscription extends Memcached_DataObject
     static function bySubscribed($subscribedId,
                                  $offset = 0,
                                  $limit = PROFILES_PER_PAGE)
+    {
+        if ($offset + $limit > self::CACHE_WINDOW) {
+            return new ArrayWrapper(self::realBySubscribed($subscribedId,
+                                                           $offset,
+                                                           $limit));
+        } else {
+            $key = 'subscription:by-subscribed:'.$subscribedId;
+            $window = self::cacheGet($key);
+            if ($window === false) {
+                $window = self::realBySubscribed($subscribedId,
+                                                 0,
+                                                 self::CACHE_WINDOW);
+                self::cacheSet($key, $window);
+            }
+            return new ArrayWrapper(array_slice($window,
+                                                $offset,
+                                                $limit));
+        }
+    }
+
+    private static function realBySubscribed($subscribedId,
+                                             $offset,
+                                             $limit)
     {
         $sub = new Subscription();
 
@@ -326,6 +386,33 @@ class Subscription extends Memcached_DataObject
 
         $sub->find();
 
-        return $sub;
+        $subs = array();
+
+        while ($sub->fetch()) {
+            $subs[] = clone($sub);
+        }
+
+        return $subs;
+    }
+
+    /**
+     * Flush cached subscriptions when subscription is updated
+     *
+     * Because we cache subscriptions, it's useful to flush them
+     * here.
+     *
+     * @param mixed $orig Original version of object
+     *
+     * @return boolean success flag.
+     */
+
+    function update($orig=null)
+    {
+        $result = parent::update($orig);
+
+        self::blow('subscription:by-subscriber:'.$this->subscriber);
+        self::blow('subscription:by-subscribed:'.$this->subscribed);
+
+        return $result;
     }
 }
-- 
2.39.2