uploadPhotoToS3.js

var AWS     = require('aws-sdk');
var fs      = require('fs');
var uuid    = require('node-uuid');

var UPLOAD_BUCKET = '';
var AWS_KEY_ID = '';
var AWS_ACCESS_KEY = '';

AWS.config.update({
    accessKeyId: AWS_KEY_ID,
    secretAccessKey: AWS_ACCESS_KEY
});

var s3 = new AWS.S3();

exports.uploadPhoto = function(req, res){
    // Get File upload information  
    var filename = req.files.image.filename; // actual filename of file
    var path = req.files.image.path; //will be put into a temp directory
    var mimeType = req.files.image.type; // image/jpeg or actual mime type

    fs.readFile(path, function(err, buffer){
        var s3Params = {
            Bucket: UPLOAD_BUCKET,
            Key: getS3Key(), 
            Body: buffer, 
            ACL:'public-read', 
            ContentType: mimeType
        };

        // Put the Object in the Bucket
        s3.client.putObject(s3Params,function(err,data) {
            if (err) {
                console.log(err);
            } else {
                console.log("Successfully uploaded data to s3 bucket");
            }
            res.send({ uploaded: true }); 
        });
    });
};

function formatDate(date) {
    var d = date.getDate();
    var m = date.getMonth() + 1;
    var y = date.getFullYear();
    return '' + y + (m <= 9 ? '0' + m : m) + (d <= 9 ? '0' + d : d);
}

function getS3Key() {
    var key = formatDate(new Date()) + '/' + uuid.v4;
}