Uploading a file to S3

s3-upload.js

require('./.env'); // AWS config is set here via process.env.

var Aws = require('aws-sdk');
var uniqid = require('uniqid');
var fs = require('fs');
var s3 = new Aws.S3();

const BUCKET_NAME = 'test-joerx';
const BUCKET_REGION = 'eu-west-1';

function bail(err) {
  if (!err) return;
  console.error(err.stack);
  process.emit('error', err);
  process.exit(1);
}

function getOrCreateBucket(conf, cb) {
  var bucketName = conf.name, bucketRegion = conf.region;
  s3.headBucket({Bucket: bucketName}, function(err, res) {
    if (err && err.statusCode === 404) {
      var params = {
        Bucket: bucketName,
        ACL: 'public-read',
        CreateBucketConfiguration: {
          LocationConstraint: bucketRegion
        }
      };
      s3.createBucket(params, function(err, res) {
        if (err) cb(err);
        else s3.waitFor('bucketExists', {Bucket: BUCKET_NAME}, cb);
      });
    } else {
      return err ? cb(err) : cb(null, {status: 'ok'});
    }
  });
}

function upload(path, bucket, key, cb) {
  var str = fs.createReadStream(path);
  var params = {
    Bucket: bucket,
    Body: str,
    ACL: 'public-read',
    Key: key
  }
  s3.upload(params, function(err, res) {
    if (err) return cb(err);
    console.log('Uploaded to ' + res.Location);
    cb(null, {location: res.Location});
  });
}

getOrCreateBucket({name: BUCKET_NAME, region: BUCKET_REGION}, function(err, res) {
  if (err) return bail(err);
  var key = uniqid();
  upload(__dirname + '/sample.jpg', BUCKET_NAME, key, function(err, res) {
    if (err) return bail(err);
    var file = fs.createWriteStream(__dirname + '/out.jpg');
    var str = s3.getObject({Bucket: BUCKET_NAME, Key: key}).createReadStream();
    str.on('end', console.log.bind(null, 'done'));
    str.pipe(file);
  });
});