Image manipulation and upload to S3

resize_and_upload_task.js

/**
 * Created by daniel on 9/29/2015.
 */
var AWS = require('aws-sdk');
AWS.config.update({accessKeyId: 'ID', secretAccessKey: 'KEY'});
AWS.config.update({region: 'us-east-1'});
var s3 = new AWS.S3();
var fileType = require('file-type');
var lwip = require('lwip');
var uuid = require('node-uuid');
var q = require('q');
var request = require('request');
var userService = require('../services/user_service');
var STATIC_BUCKET = "BUCKET_NAME";
request = q.denodeify(request);
var validator = require('validator');
var imageSizes = {
    large:{
        width:600,
        height:600
    },
    medium: {
        width:250,
        height:200
    },
    small: {
        width:100,
        height:100
    }
};
//maintain aspect ratio
function getDimensions(originalWidth,originalHeight,newWidth,newHeight){
    var dimensions = {};
    dimensions.width = originalWidth;
    dimensions.height = originalHeight;
    if(originalWidth > newWidth){
        dimensions.width = newWidth;
        dimensions.height = (dimensions.width * originalHeight)/originalWidth;
    }
    if(dimensions.height > newHeight){
        dimensions.height = newHeight;
        dimensions.width = (dimensions.height * originalWidth) / originalHeight;
    }
    return dimensions;

}
function resizeAndUpload (img){
    console.log(img);
    var deferred = q.defer();
    var getBuffer;
    if(validator.isBase64(img)){
        console.log("base!");
        var buffer = new Buffer(img, 'base64');
        getBuffer = q(buffer);
    }
    if(validator.isURL(img)){
        console.log("fb!");
        getBuffer = request({uri:img,encoding:'binary'}).then(function(args){
            console.log("request done!");
            return new Buffer(args[1].toString(),'binary');
        });
    }
    var id = uuid.v1();
    var originalWidth, originalHeight,newDimensions;
    try {
        getBuffer.then(function(body){
            console.log("get buffer");
            lwip.open(body,fileType(body).ext, function (err, img) {
                console.log("resize 1");
                originalWidth = img.width();
                originalHeight = img.height();
                newDimensions = getDimensions(originalWidth,originalHeight,imageSizes.large.width,imageSizes.large.height);
                img.resize(newDimensions.width,newDimensions.height,function(err, img){
                    console.log("resize 1 done");
                    uploadImage(img,id+"/large").then(function(){
                        console.log("upload 1");
                        originalWidth = img.width();
                        originalHeight = img.height();
                        newDimensions = getDimensions(originalWidth,originalHeight,imageSizes.medium.width,imageSizes.medium.height);
                        img.resize(newDimensions.width,newDimensions.height,function(err, img){
                            console.log("resize 2 done");
                            uploadImage(img,id+"/medium").then(function(){
                                console.log("upload 2");
                                originalWidth = img.width();
                                originalHeight = img.height();
                                newDimensions = getDimensions(originalWidth,originalHeight,imageSizes.small.width,imageSizes.small.height);
                                img.resize(newDimensions.width,newDimensions.height,function(err, img){
                                    console.log("resize 3 done");
                                    uploadImage(img,id+"/small").then(function(){
                                        console.log("resolving");
                                        deferred.resolve({photoid:id, new:false});
                                    });
                                });
                            });

                        });
                    });
                });
            });
        },function(error){
            console.log("some request error");
            console.log(error);
        }).catch(function (error) {
            console.log("some request error");
            console.log(error);
        });
    }catch(e){
        console.log("error");
    }
    return deferred.promise;
};

function uploadImage(img,path){
    console.log("test");
    var deferred = q.defer();
    img.toBuffer('jpg',function(err,buffer){
        var params = {
            Bucket: STATIC_BUCKET,
            Key: path,
            Body: buffer,
            ACL:'public-read',
            ContentType: fileType(buffer).mime
        };
        s3.putObject(params, function (err,data) {
            if (err) { throw err; }
            console.log(data);
            console.log(path);
            deferred.resolve();
        });

    });

    return deferred.promise;
};
process.on('message',function(data){
    var promises = [];

    data.images.forEach(function(img){
        var promise = img.new && img.data? resizeAndUpload(img.data) : q(img);
        promises.push(promise);
    });
    q.all(promises)
        .then(function(photos){
            console.log("then!");
            var deleteArr = [];
            if (data.user.profile.photos){
                data.user.profile.photos.forEach(function(oldPhoto){
                    var found = false;
                    photos.forEach(function(newPhoto){
                        if(newPhoto.photoid === oldPhoto.photoid){
                            found = true;
                        }
                    });
                    if(!found){
                        deleteArr.push({Key:oldPhoto.photoid});
                    }
                });
            }
            data.user.profile.photos = photos;

            if(deleteArr.length){
                console.log(deleteArr);
                s3.deleteObjects({Bucket:STATIC_BUCKET,Delete:{Objects:deleteArr}},function(err,data){
                        console.log(err);
                    console.log(data);
                });
            }
            console.log("trying to update");
            userService.updateUser(data.user).then(function(){
                console.log("updated");
                process.send(data.user);
            });

        });
});

s3_image_upload_service.js

var fork = require('child_process').fork;
var path = require('path');
var imgTask = fork(path.join(__dirname,'../tasks/resize_and_upload_task.js'));
var globalSocket = require('../objects/global-socket');
exports.resizeAndUpload = function (images,user){
    var data = {images:images,user:user};
    imgTask.send(data);
    imgTask.on("message",function(user){
        globalSocket.get().sockets.in(user.username).emit('img_upload_complete', user.profile.photos);
    });
};

Thanks for sharing. That's a really good starting point.