refactor: change fastify rate limiting config

package.json

@@ -54,4 +54,4 @@
  "extends": "@sapphire"
  },
  "packageManager": "[email protected]"
-}
+}

src/backend/lib/config.ts

@@ -16,7 +16,7 @@ export const config: Config = {
 
  rateLimits: {
  max: envParseInteger('RATE_LIMIT_MAX', 500),
- timeWindow: envParseString('RATE_LIMIT_TIME_WINDOW', '1 minute')
+ timeWindow: envParseInteger('RATE_LIMIT_TIME_WINDOW', 1000 * 60)
  },
 
  storage: {

src/backend/lib/types.ts

@@ -27,10 +27,21 @@ export interface Config {
 
 /** The rate limit configuration */
 interface RateLimitsConfig {
- /** The maximum amount of requests within the timespan {@link RateLimitsConfig.timeWindow timeWindow} */
+ /**
+ * Maximum number of requests a single client can perform inside a {@link RateLimitsConfig.timeWindow timeWindow}.
+ *
+ * It can be an async function with the signature `async (request, key) => {}` where `request` is the
+ * Fastify request object and `key` is the value generated by the `keyGenerator`. The function **must** return a number.
+ */
  max: number;
- /** The time window in which the requests count, in the {@linkplain https://github.com/zeit/ms ms} string format */
- timeWindow: string;
+ /**
+ * The duration of the time window.
+ *
+ * It can be expressed in milliseconds, as a string (in the [`ms`](https://github.com/zeit/ms) format), or as an
+ * async function with the signature `async (request, key) => {}` where `request` is the Fastify request object and
+ * `key` is the value generated by the `keyGenerator`. The function **must** return a number.
+ */
+ timeWindow: number;
 }
 
 /** The storage options */
@@ -80,7 +91,7 @@ declare module '@skyra/env-utilities' {
  KEY_LENGTH: IntegerString;
  MAX_LENGTH: IntegerString;
  RATE_LIMIT_MAX: IntegerString;
- RATE_LIMIT_TIME_WINDOW: string;
+ RATE_LIMIT_TIME_WINDOW: IntegerString;
  STORAGE_TYPE: 'file' | 'redis';
  STORAGE_HOST: string;
  STORAGE_PORT: IntegerString;

src/backend/server.ts

@@ -47,7 +47,23 @@ fastify.setErrorHandler((error, _, reply) => {
 // Register the rate limit handler
 await fastify.register(import('@fastify/rate-limit'), {
  max: config.rateLimits.max,
- timeWindow: config.rateLimits.timeWindow
+ timeWindow: config.rateLimits.timeWindow,
+ keyGenerator: (request) => {
+ console.log(request.headers);
+ const xRealIp = request.headers['x-real-ip'];
+ if (typeof xRealIp === 'string') return xRealIp;
+ return request.ip;
+ },
+ errorResponseBuilder: (_, context) => {
+ return {
+ statusCode: 429,
+ error: 'Too Many Requests',
+ message: `Rate limit exceeded. Only ${context.max} requests per ${context.after} to this service are allowed. Retry in ${context.after}ms.`,
+ date: Date.now(),
+ expiresIn: context.ttl
+ };
+ },
+ allowList: []
 });
 
 // Register Fastify Sensible for sending errors