Revert "fix user average elo counter using mongodb aggregation"

This reverts commit 260b51be90.

modules/user/src/main/UserRepo.scala

@@ -76,7 +76,7 @@ object UserRepo {
     $update($select(id), $set(("settings." + key) -> value))
 
   def getSetting(id: ID, key: String): Fu[Option[String]] =
-    $primitive.one($select(id), "settings") {
+    $primitive.one($select(id), "settings") { 
       _.asOpt[Map[String, String]] flatMap (_ get key)
     }
 
@@ -149,18 +149,20 @@ object UserRepo {
     }
 
   def idsAverageElo(ids: Iterable[String]): Fu[Int] = {
-    import reactivemongo.bson._
-    import reactivemongo.core.commands._
-    val command = Aggregate(userTube.coll.name, Seq(
-      Match(BSONDocument("_id" -> BSONDocument("$in" -> BSONArray(
-        ids map { id ⇒ BSONString(id) }
-      )))),
-      Group(BSONBoolean(true))("elo" -> SumField("$elo"))
-    ))
-    userTube.coll.db.command(command) map { stream ⇒
-      (stream.toList.headOption map { obj ⇒
-        toJSON(obj).asOpt[JsObject] flatMap { _ int "elo" }
-      }).flatten
+    val command = MapReduce(
+      collectionName = userTube.coll.name,
+      mapFunction = """function() { emit("e", this.elo); }""",
+      reduceFunction = """function(key, values) {
+  var sum = 0;
+  for(var i in values) { sum += values[i]; }
+  return Math.round(sum / values.length);
+}""",
+      query = Some {
+        JsObjectWriter write Json.obj("_id" -> $in(ids map normalize))
+      }
+    )
+    userTube.coll.db.command(command) map { res ⇒
+      toJSON(res).arr("results").flatMap(_.apply(0) int "value")
     } map (~_)
   }
 

todo

@@ -72,8 +72,6 @@ check team average elo http://en.lichess.org/inbox/benuegti#bottom
 DEPLOY p21
 ----------
 
-wait for reactivemongo fix https://github.com/zenexity/ReactiveMongo/pull/81
-
 upgrade nginx to get websocket proxying support
 upgrade elasticsearch to 0.90
 wait for https://github.com/zenexity/ReactiveMongo/issues/72