🚀 Rate Limiting: From Basic to Production Grade Implementations

A deep dive into different ways to implement rate-limiting in JavaScript, comparing tradeoffs and use cases. Let's explore 5 approaches! 🧵👇

1️⃣ Basic Rate-Limiting (Immediate Rejection)

function rateLimit(fn, delay) {
 let lastCall = 0;
 return (...args) => {
  const now = Date.now();
  if (now - lastCall < delay) {
   throw new Error(`Rate limited (wait ${delay}ms)`);
  }
  lastCall = now;
  return fn(...args);
 };
}

2️⃣ Promise-Based (Reject Fast)

function rateLimit(fn, delay) {
 let lastCall = 0;
 return (...args) => {
  const now = Date.now();
  if (now - lastCall < delay) {
   return Promise.reject(new Error('Too many requests'));
  }
  lastCall = now;
  return Promise.resolve(fn(...args));
 };
}

function rateLimit(equipment, time){
let lastExec = 0
 return (a, b) =>{
 	if(Date.now() - lastExec < time){
 	return "rate limited"
 }
 lastExec = Date.now()
 return equipment(a, b)
 }
}

function mineQueue(equipment, time){
 let lastExec = 0
 return (a, b) => {
  const now = Date.now()
  const delay = Math.max(0, lastExec + time - now)
  lastExec = now + delay
   
  return new Promise(resolve => {
   setTimeout(() => resolve(equipment(a, b)), delay)
  })
 }
}