promise.js

'use strict';

var Promise = require('bluebird');
var AWS = require('aws-sdk');

// Check if environment supports native promises
if (typeof Promise === 'undefined') {
  AWS.config.setPromisesDependency(require('bluebird'));
}


var getUserAsync = Promise.method(function(event, context, callback){
    return new Promise(function(resolve, reject){
         setTimeout(function(){ resolve(getUser(event, context, callback))}, 3000);
    });
});

function getUser(event, context, callback){
   console.log(event);
   return 'getUser Function Promisse';
}

exports.handler = function (event, context, callback) {
        getUserAsync(event, context, callback).then( function (res) {
           console.log(res);
        })
        .catch(function(err){
            console.log('error');
        });
};

exports.handler([], null, function(){});