npm i ajaxmanager --save

var ajaxmanager = require("ajaxmanager");

var ajax = ajaxmanager.create();
ajax.set({
  req: req,
  res: res
});

ajax.set({ db: db });

ajax.error("wrong data");

ajax.adderror("Error 1");
ajax.adderror("Error 2");
ajax.adderror("Error 3");

ajax.success(); // response = { error: false };

ajax.reply(file); // response = { error: false, pkg: file};

ajax.send(file); // response = file