'use strict' module.exports = function () { // 2,147,483,647 (2^31 − 1) stands for max SMI value (an internal optimization of V8). // With this upper bound, if you'll be generating 1k ids/sec, you're going to hit it in ~25 days. // This is very likely to happen in real-world applications, hence the limit is enforced. // Growing beyond this value will make the id generation slower and cause a deopt. // In the worst cases, it will become a float, losing accuracy. const maxInt = 2147483647 let nextReqId = 0 return function genReqId (req) { nextReqId = (nextReqId + 1) & maxInt return `req-${nextReqId.toString(36)}` } }