How to run findAndModify using cl-mongo?

Question

How to run findAndModify using cl-mongo?

I am trying to implement a simple message queue in MongoDB. But I can not find findAndModify to work with cl-mongo.

In the mongo shell, I can do this (reformatted for readability):

> db.queue2.insert(
{
    "data": "test",
    "date_created": new Date(),
    "date_updated": null,
    "date_completed": null,
    "state": 0
})
WriteResult({ "nInserted" : 1 })

> db.queue2.findAndModify(
{
    query: {"state": 0},
    update: {
        $inc: {"state": 1},
        $currentDate: {"date_updated": false}
    }
})
{
    "_id" : ObjectId("56e7142c3ade7afa5209bf0f"),
    "data" : "test",
    "date_created" : ISODate("2016-03-14T19:42:36.860Z"),
    "date_updated" : null,
    "date_completed" : null,
    "state" : 0
}

> db.queue2.find()
{
    "_id" : ObjectId("56e7142c3ade7afa5209bf0f"),
    "data" : "test",
    "date_created" : ISODate("2016-03-14T19:42:36.860Z"),
    "date_updated" : ISODate("2016-03-14T19:43:10.499Z"),
    "date_completed" : null,
    "state" : 1
}

I can use findin cl-mongo:

> (pp (db.find "queue2" (kv "query" (kv "state" 0))))

  {
    "_id" -> objectid(56E858283ADE7AFA5209BF10)
    "data"  -> test
    "date_created"  -> CL-MONGO::BSON-TIME Tue Mar 15 2016 19:44:56 (GMT+1)
    "date_updated"  -> NIL
    "date_completed"  -> NIL
    "state"  -> 0.0d0
  }

I am trying to run findAndModifyusing db.run-command. Reading the documentation and the cl-mongo code, I think it should be called like this:

> (pp (db.run-command "findAndModify"
            :arg (kv (kv "query" (kv "state" 0))
                     (kv "update" (kv "$inc" (kv "state" 1))))
            :collection "queue2"))

  {
    "ok"  -> 0.0d0
    "errmsg"  -> need remove or update
  }
NIL

I tried some options like :findAndModifytrying to pass parameters in a list, etc., but I keep getting the same error.

I should probably mention that I'm new to both Lisp and MongoDB, so if I missed something obvious, I apologize.