Get last inserted ID from MongoDB using Play Scala

Question

How can I get the last inserted ID? I need to get latest comments id. Please see below codes:

Snoop.findOneById(snoopId) match {
      case Some(snoop) => {
        user.groups.find(ug => ug.groupId == snoop.groupId).map { ug =>
          val prop = Property.findOneById(snoop.propertyId).get
            val comment = Comment(userId = user.id, name=user.getNameString, text = text)
            val snoopSave = snoop.copy(comments = comment :: snoop.comments)
            val sComment = Snoop.save(snoopSave)
        }
        .getOrElse(None)
      }
      case _ => None
    }

Mongodb structure :

{
   "_id": ObjectId("532725c3ff5d00682f5a0b9b"),
   "_t": "models.Snoop",
   "propertyId": ObjectId("532725bfff5d00682f5a0b99"),
   "groupId": ObjectId("529f6461e4b008b565b4358c"),
   "userId": ObjectId("532717e5ff5d00682f5a0b83"),
   "price": 995000,
   "monthlyFees": 0,
   "comments": {
     "0": {
       "_t": "models.Comment",
       "_id": ObjectId("534bce0b7d374bf1b5a170ba"),
       "userId": ObjectId("529f6461e4b008b565b4358b"),
       "name": "monmon",
       "text": "test",
       "createDate": ISODate("2014-04-14T12: 01: 15.627Z"),
       "replies": {
         "0": {
           "_t": "models.Comment",
           "_id": ObjectId("534bd1b67d374bf1b5a170be"),
           "userId": ObjectId("529f6461e4b008b565b4358b"),
           "name": "monmon",
           "text": "monnmonn",
           "createDate": ISODate("2014-04-14T12: 16: 54.752Z"),
           "replies": [

          ] 
        },
         "1": {
           "_t": "models.Comment",
           "_id": ObjectId("534bcf437d374bf1b5a170bc"),
           "userId": ObjectId("529f6461e4b008b565b4358b"),
           "name": "monmon",
           "text": "test test test",
           "createDate": ISODate("2014-04-14T12: 06: 27.896Z"),
           "replies": [

          ] 
        } 
      } 
    } 
  }

Also, I tried Get ID of last inserted document in a mongoDB w/ Java driver but did not work :

val sComment = Snoop.save(snoopSave)
ObjectId id = (ObjectId)sComment.get( "_id" );

What does Play! have to do with accessing MongoDB? Are you using a plugin or something? — vptheron, Apr 28 '14 at 15:08
You code is scala code. To access MongoDB with scala, you can use http://reactivemongo.org/ Example with Play Framework [here](https://github.com/ReactiveMongo/Play-ReactiveMongo). For Id Generation, please read [this thread](https://groups.google.com/forum/#!topic/play-framework/6vth87vERwU) — yesnault, Apr 29 '14 at 06:46

score 0 · Answer 1 · answered May 09 '14 at 11:49

hate to answer this but might help others!

-- from my research, mongodb generated ID is being done via client side, so no need to query this to sever side

Solution #1 Assign value to your ID

EX: val cID = new Object()

then include this in your save code

Solution #2 Let mongodb assign ID

EX: val comment = Comment(userId = user.id, name=user.getNameString, text = text)

Then this will return all the info together with the generated ID. You can access the ID via comment.id (in my case).

Hope this will help others

Get last inserted ID from MongoDB using Play Scala

1 Answers1