mongo array update fails when executed over AWS lambda

Question

I have the following query:

db.COLLECTIONNAME.update({ groupId:11 },{ $set: { "users.$[elem1].preferred_username": 'cmaronchick2'} },{ arrayFilters: [ {"elem1.username":'cmaronchick'} ] })

My Mongo server version is 3.6.6. I have tried this using the shell and it works.

However, when I try the same query using a Lambda function using Node.js on AWS, I get the following error:

No array filter found for identifier \'elem1\'

How do I resolve this?

Here is the connection code:

var mongo = require("mongodb").MongoClient,
assert = require("assert");

const MONGO_URL = 'mongodb://USERNAME:PASSWORD@MONGODBURL:PORT/DBNAME';

// console.log('Loading function');

exports.handler = (event, context) => {
console.log('Received event:', JSON.stringify(event, null, 2));

mongo.connect(MONGO_URL, function (err, db) {
    db.COLLECTIONNAME.update({ groupId:11 },{ $set: { "users.$[elem1].preferred_username": 'cmaronchick2'} },{ arrayFilters: [ {"elem1.username":'cmaronchick'} ] })
}

how are you connecting to the database in your Lambda? maybe it is not connecting to the right one — Edwin
– Edwin, Commented Nov 8, 2018 at 20:06
Thanks. I added the connection code. I am able to connect and retrieve data from a different collection in the same code. I think it may have something to do with the version I'm using, but I don't know how to update it. — cmaronchick
– cmaronchick, Commented Nov 8, 2018 at 20:28

Edwin · Accepted Answer · 2018-11-08 21:09:05Z

2

You could try to remove the DBNAME from the MONGO_URL and specifying the database after the connection to the server is done.

Per the documentation, the database specified in the connection string for mongo is the database that will be used to look for and authenticate the user trying to access the server, the default is admin

const MONGO_DB = DBNAME
const MONGO_URL = 'mongodb://USERNAME:PASSWORD@MONGODBURL:PORT';

mongo.connect(MONGO_URL, function (err, client) {
    let db = client.db(MONGO_DB) // <- Specifying the database
    db.COLLECTIONNAME.update({ groupId:11 },{ $set: { "users.$[elem1].preferred_username": 'cmaronchick2'} },{ arrayFilters: [ {"elem1.username":'cmaronchick'} ] })
}

It is also similar to how they do it in the official documentation

edited Nov 8, 2018 at 21:09

answered Nov 8, 2018 at 20:52

Edwin

8367 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

cmaronchick Over a year ago

Thanks for the help!

cmaronchick · Accepted Answer · 2018-11-08 21:01:53Z

0

Ok, this was a pretty silly mistake. Updating array elements was not compatible with the node_module version of mongo that I had uploaded (it was version 2.1.X and array filters were introduced in 3.1).

I updated my mongodb and mongodb-core versions to 3.1.9 and 3.1.8 (using npm update mongodb mongodb-core), respectively, and updated my code like so:

const myDB = db.db('DBNAME');
const profileCollection = myDB.collection('profile');
const groupsCollection = myDB.collection('groups');

groupsCollection.updateOne({ groupId:11 },
    { $set: { "users.$[elem1].preferred_username": 'cmaronchick1'} },
    { arrayFilters: [ {"elem1.username":'cmaronchick'} ] } )

And that worked.

answered Nov 8, 2018 at 21:01

cmaronchick

4164 silver badges16 bronze badges

Collectives™ on Stack Overflow

mongo array update fails when executed over AWS lambda

2 Answers 2

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related