streams.js

function setFileStream(stream) {
            stream.fileStream = null;
            stream.dataHandler = null;

            stream.on('data', function (data) {
                if (data.type == "start") {
                    stream.fileStream = fs.createWriteStream(data.file);
                    stream.dataHandler = function (data) {
                        stream.fileStream.write(data);
                    };

                    return;
                }

                if (data.type == "end") {
                    stream.fileStream.end();
                    stream.dataHandler = null;

                    return;
                }

                if (stream.dataHandler !== null) {
                    stream.dataHandler(data);
                }
            });
        }