From 0c3ea69cf2dfd68615963e5e879c743382712785 Mon Sep 17 00:00:00 2001
From: WcaleNieWolny <michael@capgo.app>
Date: Sun, 12 Jan 2025 05:09:40 +0000
Subject: [PATCH] feat: fork ratelimit to log instead of blocking wih 429

---
 .../functions/_backend/utils/cfRateLimiter.ts | 61 +++++++++++++++++++
 supabase/functions/import_map.json            |  1 +
 2 files changed, 62 insertions(+)
 create mode 100644 supabase/functions/_backend/utils/cfRateLimiter.ts

diff --git a/supabase/functions/_backend/utils/cfRateLimiter.ts b/supabase/functions/_backend/utils/cfRateLimiter.ts
new file mode 100644
index 000000000..02419f265
--- /dev/null
+++ b/supabase/functions/_backend/utils/cfRateLimiter.ts
@@ -0,0 +1,61 @@
+import type { Context, Next } from '@hono/hono'
+import { createMiddleware } from 'hono/factory'
+
+const RATE_LIMIT_CONTEXT_KEY = '.rateLimited'
+// const STATUS_TOO_MANY_REQUESTS = 429
+
+export interface RateLimitBinding {
+  limit: LimitFunc
+}
+
+export interface LimitFunc {
+  (options: LimitOptions): Promise<RateLimitResult>
+}
+
+interface RateLimitResult {
+  success: boolean
+}
+
+export interface LimitOptions {
+  key: string
+}
+
+export interface RateLimitResponse {
+  key: string
+  success: boolean
+}
+
+export interface RateLimitOptions {
+  continueOnRateLimit: boolean
+}
+
+export interface RateLimitKeyFunc {
+  (c: Context): string
+}
+
+export function rateLimit(rateLimitBinding: RateLimitBinding, keyFunc: RateLimitKeyFunc, rateLimit: string = '') {
+  return createMiddleware(async (c: Context, next: Next) => {
+    const key = keyFunc(c)
+    if (!key) {
+      console.warn('the provided keyFunc returned an empty rate limiting key: bypassing rate limits')
+    }
+    if (key) {
+      const { success } = await rateLimitBinding.limit({ key })
+      c.set(RATE_LIMIT_CONTEXT_KEY, success)
+
+      if (!success) {
+        // throw new HTTPException(STATUS_TOO_MANY_REQUESTS, {
+        //   res: c.text("rate limited", { status: STATUS_TOO_MANY_REQUESTS }),
+        // });
+        console.warn(`The rate limit has been reached for key: ${key} and rate limit binding: ${rateLimit}`)
+      }
+    }
+
+    // Call the next handler/middleware in the stack on success
+    await next()
+  })
+}
+
+export function wasRateLimited(c: Context): boolean {
+  return c.get(RATE_LIMIT_CONTEXT_KEY) as boolean
+}
diff --git a/supabase/functions/import_map.json b/supabase/functions/import_map.json
index af4542330..c04dc2729 100644
--- a/supabase/functions/import_map.json
+++ b/supabase/functions/import_map.json
@@ -9,6 +9,7 @@
     "hono/request-id": "jsr:@hono/hono@^4.6.13/request-id",
     "hono/cors": "jsr:@hono/hono@^4.6.13/cors",
     "hono/tiny": "jsr:@hono/hono@^4.6.13/tiny",
+    "hono/factory": "jsr:@hono/hono@^4.6.13/factory",
     "hono/http-exception": "jsr:@hono/hono@^4.6.13/http-exception",
     "hono/adapter": "jsr:@hono/hono@^4.6.13/adapter",
     "hono/utils/buffer": "jsr:@hono/hono@^4.6.13/utils/buffer",