I am having a problem using the MongoDB client for Nodejs (3.0.4), with Node (v9.8.0). The issue is that when I run a query against a database, it works when it is called one time, but not when it is called under a loop.
See the following code:
'use strict';
// Load modules
const Mongo = require('mongodb');
const MongoClient = Mongo.MongoClient;
async function runOnce() {
let result = await runBasicMongoQuery();
console.log(result);
process.exit(0);
}
async function runManyTimes() {
[1,2,3,4,5].forEach(async (x) => {
let result = await runBasicMongoQuery();
console.log(result);
});
process.exit(0);
}
async function runBasicMongoQuery() {
try {
console.log(`Creating client:`);
let client = await MongoClient.connect('mongodb://localhost:27017/test');
console.log(`\tclient: ${!!client}`);
console.log(`Creating db:`);
let db = client.db();
console.log(`\tdb: ${!!db}`);
console.log(`Retrieve collection:`);
let coll = db.collection('temp');
console.log(`\tcoll: ${!!coll}`);
console.log(`Run Query:`);
let result = await coll.find({ name: 'me' }).sort({ name: 1 }).toArray();
console.log(`\tresult: ${!!result}`);
return result;
} catch(err) {
console.log(err);
}
}
When I run the function runOnce() I get a successful execution:
Creating client: client: true Creating db: db: true Retrieve collection: coll: true Run Query: result: [ { _id: 5aabfc0763abc840a19d927c, name: 'me' } ]
When I run the command runManyTimes() I get the following response:
Creating client: Creating client: Creating client: Creating client: Creating client:
Notice that this fails silently at the MongoClient.connect(...). No error raised, no nothing.
Why is this failing when invoking the command inside a loop that uses async / await?
Thanks.
