Retrieve entry from database, fetch image, store original to S3 along with two different thumbnails.

imaginator.js

Entry.findOne({type: 'photo', photo: null}).done(function(entry) {
    var thumbnailSize = entry.authorTypeName == 'Photographer' ? 500 : 250;
    var options = uri.parse(entry.photoUrl);
    var req = http.get(options, function(res) {
        if (res.statusCode != 200) return next(new Error('Could not fetch: ' +  entry.photoUrl));

        var type = res.headers['content-type'];
        var length = res.headers['content-length'];
        var extension = mime.extension(type);
        var path = settings.s3.path + entry._id + '.' + extension;
        var headers = {
            'content-type': type,
            'content-length': length,
            'x-amz-acl': 'public-read'
        };

        async.parallel([
            function(callback) {
                s3.putStream(path, res, false, headers, function(err) {
                    callback(err);
                });
            },
            function(callback) {
                var image = gm(res);
                image.size({bufferStream: true}, function(err, size) {
                    if (err) return callback(err);

                    var factor = Math.max(thumbnailSize / size.width, thumbnailSize / size.height);
                    var width = Math.ceil(size.width * factor);
                    var height = Math.ceil(size.height * factor);
                    var offsetX = Math.round((width - thumbnailSize) / 2);
                    var offsetY = Math.round((height - thumbnailSize) / 2);


                    image.scale(width, height, offsetX, offsetY).crop(thumbnailSize, thumbnailSize);
                    image.noProfile().quality(65);

                    var storeVariant = function(variant, callback) {
                        image.stream(function(err, stream) {
                            if (err) return callback(err);

                            var buffer = new Buffers();

                            stream.on('data', buffer.push.bind(buffer));
                            stream.on('end', function() {
                                var headers = {
                                    'content-type': type,
                                    'x-amz-acl': 'public-read'
                                };

                                s3.putBuffer(path + ':' + variant, buffer.toBuffer(), false, headers, function(err) {
                                    callback(err);
                                });
                            });
                        });
                    };

                    storeVariant('thumb', function(err) {
                        if (err) return callback(err);

                        image.type('Grayscale');

                        storeVariant('thumbgs', function(err) {
                            callback(err);
                        });
                    });
                });
            }
        ], function(err) {
            entry.photo = 'http://' + settings.s3.endpoint + '/' + settings.s3.bucket + path;

            Entry.save(entry).done(function() {
                console.log('All done.');
                console.log(entry);
            });
        });
    });
});