Global

rate limiting

API
for distributed applications

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// GET rlimit.com anywhere in your code
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const namespace = "example" // your rlimit.com namespace ID
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const rate = "1/5s" // allow 1 request every 5 seconds
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const identifier = "user:123" // user ID, IP address, etc
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const limit = await fetch(`https://rlimit.com/${namespace}/${rate}/${identifier}`)
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if (!limit.ok) {
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  throw new Error('rate limited');
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}
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// continue processing the request

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import express from 'express';
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import { rateLimit } from 'express-rate-limit'
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import { Store } from '@rlimit/storage';
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const app = express();
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let rlimit = rateLimit({
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  // limit IP address to 3 requests every 5 seconds
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  limit: 3, 
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  windowMs: 5_000,
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  store: new Store({
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    namespace: 'example', // your rlimit.com namespace ID
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  })
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})
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app.use(rlimit)
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app.get('/', async (req, res) => {
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  res.send('Hello World!')
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});
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app.listen(3000, () => {
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  console.log("Express application started");
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});

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import { RateLimit } from "npm:@rlimit/http";
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// initialize rlimit.com client with your namespace ID and default settings
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const ratelimit = new RateLimit({ namespace: "example", maximum: 5, interval: "10s" });
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// increase count & check result for given identifier
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const limit = await ratelimit.check("user:123");
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console.info(limit);
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if (!limit.ok) {
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  throw new Error("rate limited!");
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}
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// continue with some logic

# GET rlimit.com/:namespace/:max/:interval/:identifier

# 1 request per 1h is allowed
curl -X GET --fail "https://rlimit.com/example/1/1h/my-script"
=> { "ok": true, "status": 200, "remaining": 0 }

# more requests within 1h will fail and script exits
curl -X GET --fail "https://rlimit.com/example/1/1h/my-script"
=> curl: (22) The requested URL returned error: 429

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// middleware.ts
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export const rateLimitMiddleware: MiddlewareHandler = async (c, next) => {
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  // read accountId from request path
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  const accountId = c.req.param("accountId")
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  // limit $accountId to 100 requests every 1h
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  const limit = await fetch(`https://rlimit.com/example/100/1h/${accountId}`)
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  if (!limit.ok) {
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      return c.text("too many requests", 429)
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  }
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  await next()
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}        
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// router.ts
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app.get("/api/:accountId/expensive-operation", rateLimitMiddleware, myHandler);

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import requests
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identifier = "user:123" # user ID, IP address, etc
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# limit "ip-address-or-user-id" to 100 requests every 1h
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limit = requests.get("https://rlimit.com/example/100/1h/" + identifier)
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if not limit.ok:
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    # rate limited
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    # for example, reject request
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    pass