Mongoose not reconnecting after disconnection event

[elizatlawy]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Mongoose version

6.10.1

Node.js version

14.18.3

MongoDB server version

5.0.9

Typescript version (if applicable)

No response

Description

My connection looks like this:

const OPTIONS = {
  useNewUrlParser: true,
  useUnifiedTopology: true
};

// Make `sanitizeFilter` true by default
mongoose.set('sanitizeFilter', true);
mongoose.set('strictQuery', true);

if (process.env.LOG_MONGO_QUERIES) {
  mongoose.set('debug', (collectionName, method, query, doc) => {
    logger.debug(`${collectionName}.${method}`, JSON.stringify(query), doc);
  });
}

const initMongooseConnection = () => {
  try {
    connection.on('connected', () => {
      logger.info(`Successfully connected to MongoDB`);
    });
    connection.on('reconnected', () => {
      logger.info(`Successfully reconnected to MongoDB`);
    });
    connection.on('error', error => {
      logger.error(`MongoDB encountered and error: ${error}`);
    });
    connection.on('connecting', () => {
      logger.info('MongoDB connecting...');
    });
    connection.once('open', () => {
      logger.info('MongoDB connection opened');
    });
    connection.on('disconnecting', () => {
      logger.info('MongoDB disconnecting...');
    });
    connection.on('disconnected', () => {
      logger.error('MongoDB disconnected');
    });
    connection.on('close', () => {
      logger.info('MongoDB connection closed');
    });
    mongoose.connect(MONGO_DB_CONNECTION_URI, OPTIONS);
  } catch (err) {
    logger.error(`Error connecting to mongoDB: ${err}`);
  }
};

If I restart my Mongodb I get the disconnected event but there is no reconnect attempt, I am able to reconnect only after restarting the Node.js server.

Steps to Reproduce

1. Start the node.js server
2. See that the Mongo connection is open
3. Restart MongoDB
4. disconnection e ent is fired
5. No reconnect attempt

Expected Behavior

Mongoose should try to reconnect.

[IslandRhythms]

const mongoose = require('mongoose');

async function run() {
  await mongoose.connect('mongodb://localhost:27017');
}

mongoose.connection.on('close', async () => {
  console.log('lost connection');
});

mongoose.connection.on('reconnect', () => console.log('reconnect'));

mongoose.connection.on('reconnected', () => console.log('reconnected'))

mongoose.connection.on('connected', () => console.log('connected'));

mongoose.connection.on('disconnected', () => console.log('disconnected'))

mongoose.connection.on('disconnecting', () => console.log('disconnecting'))

run();

[elizatlawy]

@IslandRhythms - Did you use the same version I mentioned?

I tried and the issue is still reproduced with your simple test:

[IslandRhythms]

Does not occur for me on 6.10.1