demo.js

new jmap.Client(new jmap.RequestTransport())
    .withAPIUrl('http://192.168.1.23:44333/jmap')
    .withAuthenticationToken('d13f3593-3c43-4540-9f83-46342b626696')
    .listThenGetMessages()
    .then((response) => {
        var messages = response[1][1].list;

        messages.forEach(element => {
          console.log('email has subject ' + element.subject)
        });
    }, 
    (err) => {console.log(2222, err);});