s3.js

var when = require('when');
var AWS = require('aws-sdk');
var _ = require('lodash');

var s3;
var bucket = null;

function getImage(url) {
  return when.promise(function(resolve, reject) {
    if(!bucket) {
      return reject('no bucket defined');
    }

    console.time('s3.getObject - ' + url);
    s3.getObject({
        Bucket: bucket,
        Key: url
    }, function(err, image) {
      console.log('get image from S3 - :url'.replace(':url', url));
      console.timeEnd('s3.getObject - ' + url);
      if(err) reject(err);
      if(!err) {
        image.Key = url;
        resolve(image);
      }
    });

  })
}

var saveImage = _.curry(function(name, image) {
  return when.promise(function(resolve, reject) {
    if(!bucket) {
      return reject('no bucket defined');
    }

    console.log('saving image to S3');

    s3.putObject({
        Bucket: bucket,
        Key: name,
        Body: image.Body
    }, function(err, image) {
      if(err)   reject(err);
      if(!err)  resolve(image);
    });

  });
});

function init(opts) {
  bucket = opts.bucketName;
  s3 = new AWS.S3({
    region: 'us-west-2',
    params: {
      Bucket: opts.bucketUrl
    }
  });
}

exports.getImage = getImage;
exports.saveImage = saveImage;
exports.init = init;