Commander.js - Implementing sub commands that executes when the previous one is finished

Question

I'm using Commander.js to write my own CLI. I managed to write commands that work individually but now I need to implement sub commands but the docs are a bit vague and confusing so I haven't been able to figure out.

What I want is the connect command to connect to a MongoDB instance and when it has done that proceed to execute the get command. How can I achieve this?

These are the commands and package.json:

./package.json:

{
  ...
  "main": "./commands/my-cli.js",
  "bin": "./commands/my-cli.js",
  ...
}

./commands/my-cli.js:

const commander = require('commander');
const program = new commander.Command();

const connect = require('./my-cli-connect');
const get = require('./my-cli-get');

// Initialize each command
connect(program);
get(program);

./commands/my-cli-connect.js:

function connect(program) {

  program
    .command('connect <db> <username> <password>', 'Connects to a database')
    .action((db, username, password) => {

      MongoClient.connect(<some-mongo-url>, {useNewUrlParser: true}, (err, connection) => {

        assert.equal(null, err, 'Failed to connect to MongoDB instance');

        // Continue here with the get command
      });
    }); 

  program.parse(process.argv);
}

module.exports = connect;

./commands/my-cli-get.js:

function get(program) {

  program
    .command('get <collection>')
    .option('-q,--query <query>', 'Search terms', jsonParser, {})
    .description('Returns documents from a MongoDB collection')
    .action(action);

  program.parse(process.argv);

  function action(collection, options) {

    // This never runs
    console.log('hello world');
  }
}

module.exports = get;

Running my-cli --help shows these available commands:

...

Commands:
  connect <db> <username> <password>  Connects to a database
  help [cmd]                          display help for [cmd]

Example command execution that should call both connect and then get when connect has finished connecting:

$ my-cli connect myDb myUser myPass get users -q '{"email": "foo@gmail.com"}'

Right now the get command's action function never runs.