Question 117208 in Mongodb Question posted in
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Mongodb – Calling a Field within an Object in an Async Function

In my Node.js code, the server console returns the object gameFind with a populated value for hikeEnd (it’s a Date field), but the console result for gameFind.hikeEnd, called immediately after, is undefined. This makes my equation NaN. What am I doing wrong here?

        async function saveHike() {
            await Game.updateOne({},{ $set: { hikeEnd: Date.now() } });
            
            var gameFind = await Game.find( { teamName: thisTeam } );
            console.log ('gameFind: ' + gameFind);
            console.log ('gameFind.hikeEnd: ' + gameFind.hikeEnd);
            //calculate the score
            var hikeScore = (gameFind.hikeEnd - gameFind.hikeStart) / 1000;
            console.log ('hikeScore: ' + hikeScore);

        }
        saveHike();

EDIT: console.log output

gameFind: {
  _id: new ObjectId("62df29b4ea65773e6827aa54"),
  teamName: 'a',
  captain: 's',
  score: 0,
  startTime: 2022-07-25T23:39:32.235Z,
  leavetakingsEnd: 2022-07-25T23:39:32.248Z,
  hikeStart: 2022-07-25T23:39:32.252Z,
  hikeVotes: 1,
  hikeEnd: 2022-07-25T23:39:53.835Z,
  townStart: 2022-07-25T23:39:53.838Z,
  townEnd: 1970-01-01T00:00:00.000Z,
  __v: 0
}
hikeEnd: undefined
hikeScore: NaN

Given Seth’s comments, I suppose this must be an async/await issue, but I cannot determine it. I have tried calling it with gameFind[hikeEnd] rather than a dot call but it still logs undefined. Is await Game.find being executed AFTER the console.logs because it’s in an await? This must be it, but I can’t remedy it. Thanks in advance, this has gotten quite frustrating.

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2

Answers


  1. Chosen as BEST ANSWER
    0

    The ultimate solution was to change my Game.find to Game.findOne so it returns a document rather than a cursor.


  2. 0

    I made a version of your code that doesn’t execute from the database just to see if I could mirror your output. I cannot.

    Here is my code,

    var globalGameFind= {
  teamName: 'a',
  captain: 's',
  score: 0,
  startTime: new Date("2022-07-25T23:39:32.235Z"),
  leavetakingsEnd: new Date("2022-07-25T23:39:32.248Z"),
  hikeStart: new Date("2022-07-25T23:39:32.252Z"),
  hikeVotes: 1,
  hikeEnd: new Date("2022-07-25T23:39:53.835Z"),
  townStart: new Date("2022-07-25T23:39:53.838Z"),
  townEnd: new Date("1970-01-01T00:00:00.000Z"),
  __v: 0
}
function saveHike() {
  var gameFind = globalGameFind;
  console.log('gameFind: ' + gameFind);
  console.log('gameFind.hikeEnd: ' + gameFind.hikeEnd);
  //calculate the score
  var hikeScore = (gameFind.hikeEnd - gameFind.hikeStart) / 1000;
  console.log('hikeScore: ' + hikeScore);

}
saveHike();

    And here is my output

    gameFind:

    {
    "teamName": "a",
    "captain": "s",
    "score": 0,
    "startTime": "2022-07-25T23:39:32.235Z",
    "leavetakingsEnd": "2022-07-25T23:39:32.248Z",
    "hikeStart": "2022-07-25T23:39:32.252Z",
    "hikeVotes": 1,
    "hikeEnd": "2022-07-25T23:39:53.835Z",
    "townStart": "2022-07-25T23:39:53.838Z",
    "townEnd": "1970-01-01T00:00:00.000Z",
    "__v": 0
}

    gameFind.hikeEnd: Mon Jul 25 2022 16:39:53 GMT-0700 (Pacific Daylight Time)

    hikeScore: 21.583

    What’s likely happening for you is gameFind.hikeEnd is undefined because gameFind doesn’t have a field called hikeEnd on it.

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