RE: https://gist.github.com/drtriumph/20c0fc9bdc48fc7e85f4

index.js

var fs = require('fs'),
    gcloud = require('gcloud'),
    knox = require('knox'),
    path = require('path'),
    ProgressBar = require('progress'),
    RSVP = require('rsvp'),
    tar = require('tar'),
    through = require('through2'),
    uuid = require('uuid'),
    zlib = require('zlib');

var aws = knox.createClient({
    key: '',
    secret: '',
    region: 'us-west-2',
    bucket: '',
    secure: true
  });

var gcs = gcloud.storage({
  keyFilename: '/Users/stephen/dev/keyfile.json',
  projectId: 'nth-circlet-705'
});

var gcsBucket = gcs.bucket('gcsbuckettwo');

var directory = uuid.v4();

function getWriteStream(service, fileName, opts) {
  var stream = through();

  if (service === 'google') {
    var serviceStream = gcsBucket.file(fileName).createWriteStream({
      validation: false,
      resumable: false
    });
  }

  if (service === 's3') {
    var serviceStream = aws.put(fileName, opts)
      .on('response', function() {
        stream.emit('finish');
      });
  }

  return stream.pipe(serviceStream);
}

function upload(service) {
  console.log('Uploading to', service);

  var gunzip = zlib.createGunzip(),
      untar = tar.Parse(),
      outstandingCount = 1,
      uploadedBytes = 0;

  var bar = new ProgressBar(':bar', { total: 750 });

  var start = new Date().getTime();

  return new RSVP.Promise(function(resolve, reject) {
    function checkComplete() {
      if (outstandingCount === 0) {
        var now = new Date().getTime(),
            time = now - start;
        console.log('Finished uploading to', service, 'in', time / 1000.0, ' seconds');
        resolve({
          totalBytes: uploadedBytes,
          totalTime: time
        });
      }
    }

    var extraction = fs.createReadStream('files.tar.gz').pipe(gunzip).pipe(untar).on('entry', function(entry) {
      if (entry.type === 'File') {
        outstandingCount += 1;

        var fileName = directory + '/' + entry.path.split(path.sep).slice(1).join('/');
        var writeStream = getWriteStream(service, fileName, { 'Content-Length': entry.size });

        entry.pipe(writeStream)
          .on('error', reject)
          .on('finish', function() {
            outstandingCount -= 1;
            bar.tick();
            uploadedBytes += entry.size;
            checkComplete();
          });
      }
    }).on('end', function() {
      outstandingCount -= 1;
      checkComplete();
    });
  });
}

upload('s3').then(function() {
  return upload('google');
}).catch(function(err) {
  throw(error);
});