mongoE11000.js

/*jshint esversion: 6 */

'use strict';
'use esversion 6';

const MongoClient = require('mongodb').MongoClient;
const CONNECTION_URL = 'mongodb://admin:mongo@localhost:27017';
const DB_NAME = 'testDB';
const COLLECTION = 'testCollection';

let connection;
let promises = [];

function updateWithRetry(i, db,  query, value, upsrt) {
	return db.collection(COLLECTION).updateOne(query, value, {'upsert' : upsrt})
	.then((result) => {
		return new Promise((resolve, reject) => { resolve('i: ' + i + ' time: ' + new Date().getTime());});
	})
	.catch(err => {
		if (err.code === 11000){
			console.log('i: ' + i + ' 11000 error');
			return updateWithRetry(i, db, query, value, false);
		}
		else {
			throw err;
		}
	});
}

function update(i, db,  query, value, upsrt) {
	return db.collection(COLLECTION).updateOne(query, value, {'upsert' : upsrt})
	.then((result) => {
		return new Promise((resolve, reject) => { resolve('i: ' + i + ' time: ' + new Date().getTime());});
	})
	.catch(err => {
		throw err;
	});
}

MongoClient.connect(CONNECTION_URL, {useNewUrlParser : true})
.then((result) => {
	connection = result;
	const db = connection.db(DB_NAME);
	
	for (let i=0; i<5; i++) {
		let query = {'_id': 'johnDoe'};
		let value = { $set : {'funds' : i*100}, $addToSet : {'indices' : i}};
		let p = updateWithRetry(i, db, query, value, true);
		promises.push(p);
	}
	return Promise.all(promises);
})
.then((results) => {
	results.forEach((result) => {
		console.log('result - ' + result);
	});
})
.catch(err => {
	console.log(err);	
})
.finally(() => {
	console.log('closing db connection');
	connection.close();
});

https://joeywhelan.blogspot.com/2019/01/mongodb-e11000-duplicate-key-error.html