Fixing some MongoDB issues

This is meant as a quick help for those who followed some MongoDB tutorials by WornOffKeys and getting errors like:

• Topology is closed
• Operation ... buffering timed out after 10000ms
• MongoError: server is closed

Short explanation: You're most likely continuously disconnecting and reconnecting to your database, which eventually will cause some errors.

It really is that simple and the fix is probably even simpler: Don't disconnect - only connect once and be done with it.
Your code might look like this:

await mongo().then(async (mongoose) => {
  try {
    await someSchema.findOneAndUpdate(query, update, options) // some schema operation here
  } finally {
    mongoose.connection.close()
  }
})

Now, Don't disconnect - only connect once: Remove all mongoose.connection.close() as well as the await mongo().then() part Your code should then look something like:

await someSchema.findOneAndUpdate(query, update, options) // some schema operation here

But make sure that you have connected to the database once somewhere using the await mongo().