feature(api): add rate limiter

apps/api/src/utils/rate-limiter.ts

@@ -0,0 +1,34 @@
+import { getRedisCache } from '@openpanel/redis';
+import type { FastifyInstance } from 'fastify';
+
+export async function activateRateLimiter({
+  fastify,
+  max,
+  timeWindow,
+}: {
+  fastify: FastifyInstance;
+  max: number;
+  timeWindow?: string;
+}) {
+  await fastify.register(import('@fastify/rate-limit'), {
+    max,
+    timeWindow: timeWindow || '1 minute',
+    errorResponseBuilder: (req, reply) => {
+      return {
+        statusCode: 429,
+        error: 'Too Many Requests',
+        message: 'You have exceeded the rate limit for this endpoint.',
+      };
+    },
+    redis: getRedisCache(),
+    keyGenerator(req) {
+      return (req.headers['openpanel-client-id'] ||
+        req.headers['x-real-ip'] ||
+        req.headers['x-client-ip'] ||
+        req.headers['x-forwarded-for']) as string;
+    },
+    onExceeded: (req, reply) => {
+      req.log.warn('Rate limit exceeded');
+    },
+  });
+}