Rate Limiter Algorithms
Library that provides different algorithms to perform rate limiting.
Example with Node.js
import { createServer } from "node:http";
import { RateLimiter } from "rate-limiter-algorithms";
const limiter = new RateLimiter({
algorithm: "token-bucket",
limit: 5,
windowMs: 5000,
});
const server = createServer(async (req, res) => {
const ip = req.socket.remoteAddress || "any unique key";
try {
const { isAllowed, clientData } = await limiter.consume(ip);
// set rate limiting headers
const headers = limiter.getHeaders(clientData);
for (const header of headers) {
res.setHeader(header[0], header[1]);
}
if (!isAllowed) {
res.writeHead(429, "Too many requests");
res.end("Failure");
return;
}
res.end("Success");
} catch (error) {
console.error("Error in rate limiting:", error);
}
});
server.listen(3000, "127.0.0.1", () => {
console.log("Listening on 127.0.0.1:3000");
});
Config
| Option | Type | Explanation |
|---|
algorithm | string | Values: token-bucket, fixed-window-counter, sliding-window-logs, sliding-window-counter |
windowMs | number | Duration of time in milliseconds when algorithm updates its counter. |
limit | number | Maximum amount of points that client can consume |
store | Store | Store which contains clients data based on chosen algorithm. Defaults to Memory Store |
Date Stores
Memory Store
Default in-memory option. Example:
import { RateLimiter, MemoryStore } from "rate-limiter-algorithms";
const limiter = new RateLimiter({
algorithm: "token-bucket",
limit: 5,
windowMs: 5000,
store: new MemoryStore(),
});
Redis Store
Uses rawCall function to send raw commands to Redis. Example for node-redis :
import { RateLimiter, RedisStore } from "rate-limiter-algorithms";
import { createClient } from "redis";
const client = createClient();
client.connect();
const limiter = new RateLimiter({
algorithm: "token-bucket",
limit: 5,
windowMs: 5000,
store: new RedisStore({
prefix: "rla:", // it's default prefix
rawCall: (...args: string[]) => client.sendCommand(args),
}),,
});
Raw command list:
| Library | Function |
|---|
node-redis | (...args: string[]) => client.sendCommand(args) |
ioredis | (command: string, ...args: string[]) => client.call(command, ...args) |
License
All code and documentation are (c) 2024 Eugene Shumilin and released under the MIT License
