How to return a response to the client if a connection to Mongo is not established?

Question

MongoDB

Is there a way to send a message in JSON to the client (instead of outputting to the console) when a connection to Mongo is not established (for example, it is simply not running or has crashed)?
I tried several options, this is the last one:

mongoose.connect(process.env.DATABASE, { useMongoClient: true, autoReconnect: true, reconnectInterval: 1000 }, )
  .then(() => {
    console.log('Connected to Server successfully!')
  })
  .catch((err) => {
    console.log('Unable to connect to the server. Please start the server. Error:', err.message)
    return err
  })

How to handle the error further? How to bring it to the res.jsonuser?