Mongoose's find method with $or condition does not work properly

Recently I start using MongoDB with Mongoose on Nodejs.

When I use Model.find method with $or condition and _id field, Mongoose does not work properly.

This does not work:

User.find({
  $or: [
    { '_id': param },
    { 'name': param },
    { 'nickname': param }
  ]
}, function(err, docs) {
   if(!err) res.send(docs);
});

By the way, if I remove the '_id' part, this DOES work!

User.find({
  $or: [
    { 'name': param },
    { 'nickname': param }
  ]
}, function(err, docs) {
   if(!err) res.send(docs);
});

And in MongoDB shell, both work properly.

I solved it through googling:

var ObjectId = require('mongoose').Types.ObjectId;
var objId = new ObjectId( (param.length < 12) ? "123456789012" : param );
// You should make string 'param' as ObjectId type. To avoid exception, 
// the 'param' must consist of more than 12 characters.

User.find( { $or:[ {'_id':objId}, {'name':param}, {'nickname':param} ]}, 
  function(err,docs){
    if(!err) res.send(docs);
});

I implore everyone to use Mongoose's query builder language and promises instead of callbacks:

User.find().or([{ name: param }, { nickname: param }])
    .then(users => { /*logic here*/ })
    .catch(error => { /*error logic here*/ })

Read more about Mongoose Queries.

You can also add a mix of $or and and to give your functions more flexibility, options and robustness, like so:

var ObjectId = require("mongoose").Types.ObjectId;
var idParam = new ObjectId(param.length < 12 ? "123456789012" : param);

const {nameParam, nicknameParam, ageParam} = req.params || req.body || req.query

User.find({
        $or: [{
                _id: objId
            },
            {
                name: nameParam
            },
            {
                nickname: nicknameParam
            }
        ],
        $and: [{
            age: ageParam
        }]
    },
    function (err, docs) {
        if (!err) res.send(docs);
    }
);

So this means that your find() will look for all users where (_id = idParam OR name = nameParam OR nickname = nicknameParam) AND (age = ageParam)

I hope this helps someone out there. Cheers!!!