@tsdiapi/server/src/rate-limit.ts

A fully ESM-based, modular TypeScript server built on Fastify

import rateLimit, { RateLimitOptions, RateLimitPluginOptions, errorResponseBuilderContext } from '@fastify/rate-limit';
import { FastifyRequest } from 'fastify';
import { AppOptions } from "./types.js";

const defaultRateLimit: RateLimitPluginOptions = {
    global: false, // Allows per-route rate limit configuration
    max: 100,
    timeWindow: '1 minute',
    errorResponseBuilder: (request: FastifyRequest, context: errorResponseBuilderContext) => ({
        statusCode: 429,
        error: 'Too Many Requests',
        message: `Rate limit exceeded, retry in ${context.after}`,
        expiresIn: context.after
    }),
    keyGenerator: (request: FastifyRequest) => {
        return request.ip;
    },
    skipOnError: true,
    onBanReach: (req: FastifyRequest, key: string) => {
        console.warn(`Rate limit ban reached for key: ${key}, IP: ${req.ip}`);
    },
    onExceeding: (req: FastifyRequest, key: string) => {
        console.warn(`Rate limit exceeded for key: ${key}, IP: ${req.ip}`);
    }
}

export function setupRateLimit(rateLimitOptions?: AppOptions['rateLimitOptions']): false | RateLimitPluginOptions {
    let options: RateLimitPluginOptions = defaultRateLimit;
    if (rateLimitOptions === false) return false;
    if ('function' === typeof rateLimitOptions) {
        options = rateLimitOptions(defaultRateLimit);
    } else if ('object' === typeof rateLimitOptions) {
        options = { ...defaultRateLimit, ...rateLimitOptions };
    }
    return options;
}