app/lib/carrel/site-api.server.ts

Functions

Imports

It imports app/lib/carrel/site-adapter.server.ts, app/lib/context.ts, app/lib/rate-limit.mjs. Imported by app/routes/api.carrel.v1.$.ts.

Source

1// Mounts the site-api package for one request: the adapter, Carrel's key and the site's limiter.
2// Here rather than in the route because the key is a secret, and secrets are read only in .server
3// modules (check:secrets).
4
5import { createSiteApi, type RateLimiter } from "@dustinedwards/site-api";
6import { data, type RouterContextProvider } from "react-router";
7
8import { carrelSiteAdapter } from "~/lib/carrel/site-adapter.server";
9import { documentHandlerContext, getEnv, getExecutionContext } from "~/lib/context";
10import { limitHit } from "~/lib/rate-limit.mjs";
11
12const CARREL_RATE_LIMIT = 120;
13const CARREL_RATE_PERIOD_SECONDS = 60;
14
15/**
16 * The site's own limiter, the ASK_BUDGET Durable Object, under a `carrel:` prefix. Not a `ratelimit`
17 * binding: measured here, that binding refused 1, 2, 9 and 0 of twelve concurrent requests against a
18 * limit of five (wrangler.jsonc.example). A missing limiter throws, which the package fails closed on.
19 */
20function carrelLimiter(env: Env): RateLimiter {
21  return {
22    async limit({ key }) {
23      const verdict = await limitHit(env, `carrel:${key}`, CARREL_RATE_LIMIT, CARREL_RATE_PERIOD_SECONDS);
24      if (verdict.status === "unavailable") throw new Error("the rate limiter is unavailable");
25      return { success: verdict.status === "ok" };
26    },
27  };
28}
29
30/** The package guards in order: prefix, rate limit, key, route. Off the prefix is a 404. */
31export async function handleCarrelRequest(
32  request: Request,
33  context: Readonly<RouterContextProvider>,
34): Promise<Response> {
35  const env = getEnv(context);
36  const api = createSiteApi({
37    adapter: carrelSiteAdapter({
38      env,
39      ctx: getExecutionContext(context),
40      origin: new URL(request.url).origin,
41      renderDocument: context.get(documentHandlerContext),
42    }),
43    key: env.CARREL_SITE_KEY,
44    limiter: carrelLimiter(env),
45  });
46  if (!api.matches(request)) throw data("Not found", { status: 404 });
47  return api.handle(request);
48}