const { randomUUID } = require("crypto");

const SAFE_REQUEST_ID = /^[A-Za-z0-9_-]{8,128}$/;

module.exports = (req, res, next) => {
  const supplied = req.get("x-request-id");
  req.id = supplied && SAFE_REQUEST_ID.test(supplied) ? supplied : randomUUID();
  res.setHeader("X-Request-ID", req.id);
  next();
};