feat: implement caching for file info, add rate limiting, and enhance upload handling with retry logic

src/utils/rateLimit.ts

@@ -1,7 +1,57 @@
-export const checkRateLimit = (_key: string): boolean => {
+import logger from './logger';
+
+// Simple sliding window rate limiter
+interface RateLimitEntry {
+  count: number;
+  resetTime: number;
+}
+
+const rateLimitStore = new Map<string, RateLimitEntry>();
+const WINDOW_SIZE_MS = 60000; // 1 minute window
+const MAX_REQUESTS_PER_WINDOW = 100; // 100 requests per minute per IP
+
+export const checkRateLimit = (key: string): boolean => {
+  const now = Date.now();
+  const entry = rateLimitStore.get(key);
+
+  // No entry or window expired - create new entry
+  if (!entry || now > entry.resetTime) {
+    rateLimitStore.set(key, {
+      count: 1,
+      resetTime: now + WINDOW_SIZE_MS,
+    });
+    return true;
+  }
+
+  // Check if limit exceeded
+  if (entry.count >= MAX_REQUESTS_PER_WINDOW) {
+    logger.warn('Rate limit exceeded', { key, count: entry.count });
+    return false;
+  }
+
+  // Increment counter
+  entry.count++;
   return true;
 };
 
 export const cleanupRateLimitCache = (): void => {
-  // No-op karena rate limit dinonaktifkan
+  const now = Date.now();
+  let cleaned = 0;
+
+  for (const [key, entry] of rateLimitStore.entries()) {
+    if (now > entry.resetTime) {
+      rateLimitStore.delete(key);
+      cleaned++;
+    }
+  }
+
+  if (cleaned > 0) {
+    logger.debug('Rate limit cache cleanup', { cleaned, remaining: rateLimitStore.size });
+  }
 };
+
+export const getRateLimitStats = () => ({
+  trackedIPs: rateLimitStore.size,
+  windowSize: WINDOW_SIZE_MS,
+  maxRequests: MAX_REQUESTS_PER_WINDOW,
+});