mongoose virtual populate returnCount option

I am using mongoose v4.5.3

I am guessing, virtual populate method use find to populate data or findOne method when justOne is set to true. Can you please add returnCount option when it uses count query and populate document count?

Or please guide me to make the changes by myself so that I could give you a PR.

[vkarpov15]

Will add this for 5.4 👍

[nguyentrongbang]

I indeed like this feature. I’m building a restful api system that responses all data by calling a single request. But the limitation is that mongoose cannot return the count of the population field. It leads to the difficulty of paging because we don’t know the total records of populated objects. Without this, I must call some queries to just get the total records.

It’s very great if mongoose has an option that can choose returning only data, only count or both.

For example:

Only data:

{
  "status": "ok",
  "data": {
    "_id": "582992e76101e20c2100711a",
    "songs": [
      {
        "_id": "582992fa6101e20c2101f205",
        "id": 791
      },
      {
        "_id": "582992fa6101e20c2101f4e2",
        "id": 1541
      },
      {
        "_id": "582992fa6101e20c2101f63b",
        "id": 1899
      },
      {
        "_id": "582992fa6101e20c2101f65c",
        "id": 1932
      },
      {
        "_id": "582992fa6101e20c2101f674",
        "id": 1956
      }
    ]
  }
}

Only count:

{
  "status": "ok",
  "data": {
    "_id": "582992e76101e20c2100711a",
    "songs": 100
  }
}

Or both:

{
  "status": "ok",
  "data": {
    "_id": "582992e76101e20c2100711a",
    "songs": {
        "data": [
      {
        "_id": "582992fa6101e20c2101f205",
        "id": 791
      },
      {
        "_id": "582992fa6101e20c2101f4e2",
        "id": 1541
      },
      {
        "_id": "582992fa6101e20c2101f63b",
        "id": 1899
      },
      {
        "_id": "582992fa6101e20c2101f65c",
        "id": 1932
      },
      {
        "_id": "582992fa6101e20c2101f674",
        "id": 1956
      }
    ],
        "count": 100 
    }
  }
}