v4.js

#!/usr/bin/env node

const request = require('request');
const aws4 = require('aws4');
const AWS = require('aws-sdk');

let chain = new AWS.CredentialProviderChain();
chain.resolve((err, awscreds) => {
    let awsreq = aws4.sign({
        service: 'sts',
        region: 'us-east-1',
        method: 'POST',
        path: '/?Action=GetSessionToken&Version=2011-06-15',
        headers: {
            'Content-Type': 'application/x-amz-json-1.1'
            //'X-Amz-Target': 'STS.GetSessionToken'
        },
        body: JSON.stringify({})
    }, {
        secretAccessKey: awscreds.secretAccessKey,
        accessKeyId: awscreds.accessKeyId
    });

    request.post({
        url: 'https://' + awsreq.hostname + awsreq.path,
        headers: awsreq.headers,
        body: awsreq.body
    }, function(err, httpResponse, body) {
        if (err) {
            console.log(err);
        }

        console.log(httpResponse.toJSON());

        console.log(body);
    });
})