push() and save() leaks it's query on the next save() as well

Overview

When saving() an operation, queries from a previous operation that was already saved appear in the next save() query as well

What I do

I call the below method (in rapid succession) with msg.action flags that fall:

• The "newBoard" case, which simply push-es an item into an array
  • I then save()
• The switchBoard case, which simply toggles a value, that lies outside of the array
  • I then save()

I’m expecting to see mongoose sending 2 distinct queries:

• A push query to push the item into the this.boardBucket.items Array
• A set query to set the value boardBucket.currentBoardId

The problem

Mongoose sends 2 queries but both contain the pushAll command

Why does this happen? How can I ameliorate this?

The code

This is the method that get’s called which does the operations:

roomSchema.methods.applyOperation = function(msg, options) {
  options = options || {};

  // Adding the below `console.log` to confirm in the logs that this function
  // is indeed called only *twice*
  console.log("Operation " + msg.action);

  switch (msg.action) {
    case "setBoardBucket":
      this.set("boardBucket", msg.msg.boardBucket);
      break;
    case "newBoard":
      this.boardBucket.items.push(msg.msg.board);
      break;
    case "switchBoard":
      this.set("boardBucket.currentBoardId", msg.msg.boardId);
      break;
  }

  this.save((err, result) => {
    if (err) console.log(err);
  })
}

The Mongoose logs:

As you can see there are 2 distinct queries with both containing a $pushAll command

Operation newBoard
Mongoose: rooms.update({ _id: ObjectId("57b5c537e88db17f17012578") }, { '$pushAll': { 'boardBucket.items': [ { boardId: '147705812266', viewPosition: '{x: 0, y: 0}', _id: ObjectId("57b5c7c28d08643f18640332"), undoedItems: [], boardItems: [] } ] } })
Operation switchBoard
Mongoose: rooms.update({ _id: ObjectId("57b5c537e88db17f17012578") }, { '$set': { 'boardBucket.currentBoardId': '147705812266' }, '$pushAll': { 'boardBucket.items': [ { boardId: '147705812266', viewPosition: '{x: 0, y: 0}', _id: ObjectId("57b5c7c28d08643f18640332"), undoedItems: [], boardItems: [] } ] } })

[vkarpov15]

Yes you should. Mongoose does track changes, but it keeps the changes until the document has been successfully saved (in other words, if an error occurs in save, mongoose still retains all the changes so you can retry), so you should wait until one save has finished before calling another on that same document.

[nicholaswmin]

Guess that’s another way to hit it - I’ll test both