docs: add symbol docs

throttle.ts

@@ -1,28 +1,51 @@
 import { Request, Response, NextFunction } from 'express';
 
+/**
+ * Options for configuring the rate limiter middleware.
+ */
 interface RateLimitOptions {
-  windowMs: number; // Window time in milliseconds
-  maxRequests: number; // Max number of requests per window per IP
+  /** Window time in milliseconds for rate limiting. */
+  windowMs: number;
+  /** Maximum number of requests allowed per window per IP. */
+  maxRequests: number;
 }
 
-// Simple in-memory store
+/**
+ * Simple in-memory store for tracking request timestamps.
+ */
 class MemoryStore {
+  /** Object to store hit timestamps keyed by IP. */
   hits: { [key: string]: number[] } = {};
 
+  /**
+   * Increments the count for a given key within the rate limit window.
+   * @param key The key to increment, typically the IP address.
+   */
   increment(key: string) {
     const now = Date.now();
     if (!this.hits[key]) {
       this.hits[key] = [];
     }
     this.hits[key].push(now);
-    this.hits[key] = this.hits[key].filter(timestamp => now - timestamp <= 60000); // Keep only the timestamps within the last minute
+    // Remove timestamps outside the current window
+    this.hits[key] = this.hits[key].filter(timestamp => now - timestamp <= 60000);
   }
 
-  getCount(key: string) {
+  /**
+   * Retrieves the count of hits for a given key.
+   * @param key The key for which to retrieve the count.
+   * @returns The number of hits for the key.
+   */
+  getCount(key: string): number {
     return this.hits[key] ? this.hits[key].length : 0;
   }
 }
 
+/**
+ * Creates a rate limiting middleware function.
+ * @param options The configuration options for the rate limiter.
+ * @returns An Express middleware function for rate limiting.
+ */
 export const rateLimiter = (options: RateLimitOptions) => {
   const { windowMs, maxRequests } = options;
   const store = new MemoryStore();