save array of objects to the mongo database using node, express - arrays

Question

I am trying to pre-load array of objects to MongoDB as below:
the below code works if I do one object at a time. that is,
if I set:
tmp_obj = {
id:1,
name: 'Tmp 1'
}
model file
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var TmpSchema = new Schema({
id: Number,
name: String
});
var Tmp= mongoose.model('Tmp', TmpSchema);
module.exports = Tmp;
routes file
var express = require('express');
var router = express.Router();
var Tmp = require('../models/tmp');
var tmp_obj = [
{
id:1,
name: 'Tmp 1'
},
{
id:2,
name: 'Tmp 2'
},
{
id:3,
name: 'Tmp 3'
}
];
var tmp = new Tmp(tmp_obj);
tmp.save(function (err) {
if (err) return console.log(err);
console.log('tmp saved to the database');
return res.redirect('/login');
})
how do I push an array of objects to the mongo? and also I have multiple collections to add. so, do I do something like:
tmp1.save(function (err) {
if (err) return console.log(err);
console.log('tmp1 saved to the database');
tmp2.save(function (err) {
if (err) return console.log(err);
console.log('tmp2 saved to the database');
return res.redirect('/login');
})
})

Answer 1

Another alternative is to use .create() method, it could accept an array of objects or a single object, and you don't need to create a model instance (i.e var tmp = new Tmp(tmp_obj);), here is an example:
var Tmp = require('../models/tmp');
var tmp_obj = [
{ id:1, name: 'Tmp 1' },
{ id:2, name: 'Tmp 2' },
{ id:3, name: 'Tmp 3' }
];
Tmp.create(tmp_obj, function (err, temps) {
if (err) {
console.log(err);
// terminate request/response cycle
return res.send('Error saving');
}
res.redirect('/login');
});
One last thing, don't forget to terminate the request/response cycle if an error has been occurred, otherwise the page will hangs

Answer 2

You can use the method insertMany from mongoose to insert multiple document at once.
From the documentation of mongoose v5.0.4
var arr = [{ name: 'Star Wars' }, { name: 'The Empire Strikes Back' }];
Movies.insertMany(arr, function(error, docs) {});
An alternative using .save() would be
// Create all objects
const objects = tmp_obj.map(x => new Tmp(x));
try {
// Saves objects
const docs = await Promise.all(objects.map(x => x.save()));
} catch(e) {
// An error happened
}
But you should not use it since insertMany is way better