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  1. Node.js Driver
  2. NODE-1231

Cursor.forEach should support returning a Promise

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    • Type: Icon: Improvement Improvement
    • Resolution: Fixed
    • Priority: Icon: Minor - P4 Minor - P4
    • 3.1.0
    • Affects Version/s: 3.0.0, 2.2.33
    • Component/s: MongoDB 3.4
    • Labels:
    • Environment:
      Any

      At the moment. cursor.forEach is returning undefined.
      So this code:

      var mongo = require('mongodb')
var pms = require('util').promisify

;(async function () {
  try {
    var db = await pms(mongo.MongoClient.connect)('mongodb://localhost/whatever', {})
    var usersImages = db.collection('usersImages')

    var images = await usersImages.find({})

    var i = await images.forEach(image => {
      console.log(image.image)
    })
    console.log("RETURNED:", i)

    console.log('END OF CYCLE')
  } catch (e) {
    console.error('Error:', e)
  }
})()

      Doesn't work as expected, as RETURNED will be undefined and "END OF CYCLE" will display right away, before the resultset is returned.

      This works:

      var mongo = require('mongodb')
var pms = require('util').promisify

;(async function () {
  try {
    var db = await pms(mongo.MongoClient.connect)('mongodb://localhost/whatever', {})
    var usersImages = db.collection('usersImages')

    var images = await usersImages.find({})

    images.forEachPms = pms(images.forEach)

    var i = await images.forEachPms(image => {
      console.log(image.image)
    })
    console.log("RETURNED:", i)

    console.log('END OF CYCLE')
  } catch (e) {
    console.error('Error:', e)
  }
})()

      Here I basically promisify manually the forEach call.

            Assignee:
            rebecca.weinberger Rebecca Weinberger
            Reporter:
            mercmobily Tony Mobily
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              Created:
              Updated:
              Resolved: