Bun

UNKEY_ROOT_KEY="unkey_..."

import { Ratelimit } from "@unkey/ratelimit";

// Create limiter instance
const limiter = new Ratelimit({
  rootKey: Bun.env.UNKEY_ROOT_KEY!,
  namespace: "bun-api",
  limit: 10, // 10 requests...
  duration: "60s", // ...per minute
});

const server = Bun.serve({
  async fetch(req) {
    const url = new URL(req.url);

    // Public route
    if (url.pathname === "/") {
      return Response.json({ message: "Welcome! Try /api/data" });
    }

    // Rate-limited route
    if (url.pathname === "/api/data") {
      // 1. Identify the user
      const identifier =
        req.headers.get("x-user-id") ??
        req.headers.get("x-forwarded-for") ??
        "anonymous";

      // 2. Check the rate limit
      const { success, remaining, reset } = await limiter.limit(identifier);

      // 3. Set headers
      const headers = {
        "X-RateLimit-Limit": "10",
        "X-RateLimit-Remaining": remaining.toString(),
        "X-RateLimit-Reset": reset.toString(),
      };

      if (!success) {
        return Response.json(
          { error: "Too many requests. Try again later." },
          { status: 429, headers },
        );
      }

      // 4. Request allowed
      return Response.json(
        { message: "Here's your data!", remaining },
        { headers },
      );
    }

    return Response.json({ error: "Not found" }, { status: 404 });
  },
  port: 3000,
});

console.log(`Server running at http://localhost:${server.port}`);