Quick Start

name = "my-api"
main = "src/index.ts"
compatibility_date = "2026-05-01"

[[ratelimits]]
name = "API_LIMIT"
limit = 2
period = 10

interface RateLimiter {
  limit(options: { key: string }): Promise<{ success: boolean }>;
}

interface Env {
  API_LIMIT: RateLimiter;
}

export default {
  async fetch(request: Request, env: Env): Promise<Response> {
    // Only trust this header when an authenticated upstream sets it.
    const userId = request.headers.get("x-authenticated-user-id");
    if (!userId) {
      return Response.json({ error: "Unauthorized" }, { status: 401 });
    }

    const { success } = await env.API_LIMIT.limit({ key: userId });
    if (!success) {
      return Response.json(
        { error: "Rate limit exceeded" },
        {
          status: 429,
          headers: { "Retry-After": "10" },
        },
      );
    }

    return Response.json({ ok: true });
  },
};

telnyx-edge ship

curl -i -H 'x-authenticated-user-id: user-123' https://<function-url>
curl -i -H 'x-authenticated-user-id: user-123' https://<function-url>
curl -i -H 'x-authenticated-user-id: user-123' https://<function-url>