AWS CredentialProviderChain example in aws-sdk of NodeJS

aws-get-credentials.js

'use strict';

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


var aws_region  = process.env['AWS_REGION'] ? process.env['AWS_REGION'] : 'us-west-2'
var aws_profile = process.env['AWS_PROFILE'] ?  process.env['AWS_PROFILE'] : 'default'

AWS.CredentialProviderChain.defaultProviders = [
  function () { return new AWS.EnvironmentCredentials('AWS'); },
  function () { return new AWS.EnvironmentCredentials('AMAZON'); },
  function () { return new AWS.SharedIniFileCredentials({profile: aws_profile ? aws_profile : 'default' }); },
  function () { return new AWS.EC2MetadataCredentials(); }
];

var chain = new AWS.CredentialProviderChain();

chain.resolve((err, cred)=>{
	AWS.config.credentials = cred;
})

AWS.config.update({ region: aws_region });

/*
const ec2 = P.promisifyAll(new AWS.EC2())

exports.handler = (event, context, cb) => {
	console.log(event)
	ec2.describeSecurityGroupsAsync()
		.then(data=> cb(null, data))
}
*/

Depending on how you're using this gist, it may not work: chain.resolve has a callback and anything you want to do with AWS should happen in that callback!

Let's make it support ECS :)

function () {
  if (AWS.ECSCredentials.prototype.isConfiguredForEcsCredentials()) {
    return new AWS.ECSCredentials();
  }
  return new AWS.EC2MetadataCredentials();
}

instead of

function () { return new AWS.EC2MetadataCredentials(); }