Stop deprecation of pre-connected DB object

[ctrlsam]

winston-mongodb: preconnected object support is deprecated and will be removed in v5

Using a preconnected DB object is useful when you're already using MongoDB in your program.
I've searched around and cannot find a reason for this feature to be deprecated, nodejs is now far past v5 too.

If there is a reason to keep this deprecation, I'd like to know why, and otherwise the warning should be removed.

[waynehaffenden]

+1

[wbt]

The appearance of the warning indicates use of a deprecated function; is this request to just remove the warning as stated or to remove the deprecation?

For history, the warning was added in this commit by @yurijmikhalevich on Mar 13, 2019, nominally to fix an issue around incompatibility with an updated MongoDB driver.

I'm not an expert in this topic but am adding a response assignment to someone who knows more on this topic than I; please feel free to decline if need be!

[ctrlsam]

I think a lot of people use the "depreciated" preconnected object. It would be good if this was considered to no longer be depreciated, and remove the warning

[ContraHacker]

We're missing key info here. Like @ctrlsam asked, why is it being deprecated? Also, what is the now-recommended way of creating and connecting to a MongoDB transporter?

Edit: I found out that I can simply pass the mongo connection URI to the options and everything works. This is good enough for me.

[hampusolsen]

Will using a connection string not needlessly establish a new connection?

EDIT: If I'm not mistaken it seems as if a new connection is always created no matter what you pass as the db option.

winston-mongodb.js#L134

function connectToDatabase(logger) {
  return mongodb.MongoClient.connect(logger.db, logger.options
  ).then(client=>{
    logger.mongoClient = client;
    setupDatabaseAndEmptyQueue(client.db());
  }, err=>{
    console.error('winston-mongodb: error initialising logger', err);
    if (options.tryReconnect) {
      console.log('winston-mongodb: will try reconnecting in 10 seconds');
      return new Promise(resolve=>setTimeout(resolve, 10000)
      ).then(()=>connectToDatabase(logger));
    }
  });
}

Though, passing a db object seems to work just fine with versions below.

mongodb 3.7.3
winston 3.3.5
winston-mongodb 5.0.7

Then I will opt for using a connection uri just to rid of the deprecation warning.

[ctrlsam]

The benefit I can see with using a pre-connected object is that it prevents opening another connection to the DB if the pre-connected instance is already in use. It works fine, however there is a warning generated.

[zhifeng-heng]

I am also facing an issue whereby too many mongodb connection is being created after upgrading to v5 and using the mongodb connection URI. Previously on older version i was using a pre-connected mongodb connection obj and this did not happen.

Can i get some advice on how should i do this instead? Or i probably will need to downgrade to use v4 instead.

I am using:

• Node 18.7
• Mongodb 4.9.0
• Winston 3.8.1
• Winston-Mongodb 5.0.7

Thanks!

[zhifeng-heng]

Just to provide an update.

I have created a brand new nodejs project from scratch using the latest versions (listed below) and i am still getting an error "unhandledRejection TypeError: client.db is not a function" when i use a pre-connected mongodb client obj.

Versions:
NodeJS - 18.7
MongoDB - 4.11.0
Winston - 3.8.2
Winston-Mongodb - 5.1.0

This is my code snippets.

const winston = require('winston');
const { MongoClient } = require('mongodb');
require('winston-mongodb');

const MongoDbLogClient = async () => {
const mongoClient = await MongoClient.connect('mongodb://localhost:27017/logs');
const mongodb = await mongoClient.db();
return mongodb;
};
const mongodb = MongoDbLogClient();

const logger = winston.createLogger({
transports: [
// MongoDB transport
new winston.transports.MongoDB({
level: 'info',
db: mongodb,
collection: 'server_logs'
})]
});

logger.info('Info log');

[Cristian48]

tengo el mismo problema el error que me sale es

[1] error: WORKER unhandledRejection
[1] error: uncaughtException: db.close is not a function
[1] TypeError: db.close is not a function
[1] at /app/node_modules/winston-mongodb/lib/winston-mongodb.js:87:10
[1] at processTicksAndRejections (internal/process/task_queues.js:95:5)