Fix kataras#726

My second mistake on redis session db because I'm not personally use redis, so I'm waiting for redis users to find these type of errors inside it, such as @sy264115809


Former-commit-id: df84348df7509c0f863f41f01de6ed6db6e8133e

sessions/sessiondb/redis/database.go

@@ -54,12 +54,17 @@ func (db *Database) Load(sid string) (storeDB sessions.RemoteStore) {
 		return
 	}
 
-	storeDB, ok := storeMaybe.(sessions.RemoteStore)
+	storeB, ok := storeMaybe.([]byte)
 	if !ok {
+		golog.Errorf("something wrong, store should be stored as []byte but stored as %#v", storeMaybe)
+		return
+	}
+
+	storeDB, err = sessions.DecodeRemoteStore(storeB) // decode the whole value, as a remote store
+	if err != nil {
 		golog.Errorf(`error while trying to load session values(%s) from redis:
-		the retrieved value is not a sessions.RemoteStore type, please report that as bug, it should never occur`,
+		the retrieved value is not a sessions.RemoteStore type, please report that as bug, that should never occur`,
 			sid)
-		return
 	}
 
 	return