const server = express();

ExpressExport.applyMiddleware(server);

const data = [
  { user: "Maxim", age: 22, location: "Moscow" },
  { user: "Valentina", age: 18 }
];
const fields = ["user", "age"];

server.get("/", function(req, res, next) {
  res.export({
    format: req.query.format as ExportFormat, // csv | xml | json
    filename: "users",
    data,
    fields,
    download: false
  });
});