diff --git a/webapp/bootstrap/constant.php b/webapp/bootstrap/constant.php
index aab950e3..76458d5d 100644
--- a/webapp/bootstrap/constant.php
+++ b/webapp/bootstrap/constant.php
@@ -3,6 +3,7 @@
 define('TEAMID_KEY', 'team_uuid:');
 define('RANKING_KEY', 'game2006api:');
 define('DAILY_SELECTION_KEY', 'game2006api:daily_selection:');
+define('PLANET_BUY_KEY', 'game2006api:planet_buy:');
 
 define('LAST_SESSION_KEY', 'last_session:');
 
diff --git a/webapp/controller/OutAppPlanetController.class.php b/webapp/controller/OutAppPlanetController.class.php
index 69edda92..8c372057 100644
--- a/webapp/controller/OutAppPlanetController.class.php
+++ b/webapp/controller/OutAppPlanetController.class.php
@@ -50,4 +50,18 @@ class OutAppPlanetController extends BaseController {
 
     }
 
+    private function load($period)
+    {
+        $rawData = myself()->_getRedis('')->get(PLANET_BUY_KEY . $period);
+        if (empty($rawData)) {
+            return array();
+        }
+        return json_decode($rawData, true);
+    }
+
+    private function save($data)
+    {
+        myself()->_getRedis('')->get(PLANET_BUY_KEY . $period, json_encode($data));
+    }
+
 }