From 99b2c268b2ea3fc9d6448efeaf68ef0f1717bbec Mon Sep 17 00:00:00 2001
From: Nick Winter <livelily@gmail.com>
Date: Thu, 26 Feb 2015 18:32:59 -0800
Subject: [PATCH] Also caching Aggregates.

---
 server/commons/database.coffee     |  6 +++++-
 server/levels/level_handler.coffee | 10 +++++-----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/server/commons/database.coffee b/server/commons/database.coffee
index 65b06159a..13a485ab4 100644
--- a/server/commons/database.coffee
+++ b/server/commons/database.coffee
@@ -14,7 +14,11 @@ module.exports.connect = () ->
   mongoose.connect address
   mongoose.connection.once 'open', -> Grid.gfs = Grid(mongoose.connection.db, mongoose.mongo)
 
-  mongooseCache.install(mongoose, {max: 200, maxAge: 1 * 60 * 1000, debug: false})
+  # Hack around Mongoose not exporting Aggregate so that we can patch its exec, too
+  # https://github.com/LearnBoost/mongoose/issues/1910
+  Level = require '../levels/Level'
+  Aggregate = Level.aggregate().constructor
+  mongooseCache.install(mongoose, {max: 200, maxAge: 1 * 60 * 1000, debug: false}, Aggregate)
 
 module.exports.generateMongoConnectionString = ->
   if not testing and config.mongo.mongoose_replica_string
diff --git a/server/levels/level_handler.coffee b/server/levels/level_handler.coffee
index d3060c173..11bdbd4ce 100644
--- a/server/levels/level_handler.coffee
+++ b/server/levels/level_handler.coffee
@@ -160,13 +160,13 @@ LevelHandler = class LevelHandler extends Handler
         if err then @sendDatabaseError(res, err) else @sendSuccess res, results
 
   getHistogramData: (req, res, slug) ->
-    query = Session.aggregate [
+    aggregate = Session.aggregate [
       {$match: {'levelID': slug, 'submitted': true, 'team': req.query.team}}
       {$project: {totalScore: 1, _id: 0}}
     ]
-    #query.cache()  # TODO: implement caching for aggregates
+    aggregate.cache()
 
-    query.exec (err, data) =>
+    aggregate.exec (err, data) =>
       if err? then return @sendDatabaseError res, err
       valueArray = _.pluck data, 'totalScore'
       @sendSuccess res, valueArray
@@ -290,11 +290,11 @@ LevelHandler = class LevelHandler extends Handler
           sessionQueryParams['team'] = team
           aggregate = Session.aggregate [
             {$match: sessionQueryParams}
-            {$project: {'totalScore': 1}}
             {$sort: {'totalScore': -1}}
             {$limit: 20}
+            {$project: {'totalScore': 1}}
           ]
-          #aggregate.cache()  # TODO: implement caching for aggregates
+          aggregate.cache()
           aggregate.exec cb
 
         async.map teams, findTop20Players.bind(@, sessionsQueryParameters), (err, map) =>