reactivemongo

I need to utilize MongoDB's aggregation framework using ReactiveMongo. I only find this example which uses BSON. I would like to use JSON so I changed the code to : def populatedStates(col: JSONCollection) = { import col.BatchCommands.AggregationFramework.{AggregationResult, Group, Match, SumField} val res: Future[AggregationResult] = col.aggregate( Group(JsString("$state"))("totalPop" -> SumField("population")), List(Match(JSONDocument("totalPop" -> JSONDocument("$gte" -> 10000000L))))) res.map(_.firstBatch) } But there's no "JSONDocument" type. What would be the correct way to finish this

I have a quite common use case - a list of comments. Each comment has an author. I'm storing the reference from a comment to the author using a reference, since an author can make multiple comments. Now I'm working with ReactiveMongo and want to try to keep the database access asynchronous, but in this case, I don't know how. I do an asynchronous access to the database, to get the comments, but then for each comment I have to get the author, and until now the only way I know is to loop through the comments and get the user synchronously: val userOption:Option[JsObject] = Await.result