Files
freno-dev/src/middleware.ts

103 lines
4.2 KiB
TypeScript

// @refresh reload
/* eslint-disable @typescript-eslint/no-explicit-any */
/**
* In-app host-based subdomain path rewrite.
*
* ## Why this exists
*
* `vercel.json` declares host `rewrites` that map each subdomain onto its
* internal `src/routes/<prefix>/*` file route (e.g.
* `lineage.freno.me/privacy` → `/lineage/privacy`). When Vercel builds with
* the Nitro `vercel` preset, however, it emits a Build Output API
* `.vercel/output/config.json` with a `routes` array — and per Vercel's
* contract, **a `routes` array in `config.json` fully replaces
* `vercel.json` `rewrites`/`redirects`/`headers`**. The host rewrites were
* therefore silently never applied, which is why subdomain-only routes
* (`/privacy`, `/deletion`) 404'd on production while routes that also
* exist at the root (`/`, `/contact`, `/downloads`) appeared to work (they
* were actually served by the root route, not the subdomain-branded one).
*
* ## What this does
*
* This middleware (registered via `app.config.ts` → `middleware`) runs as
* an H3 `onRequest` hook BEFORE the SolidStart file router matches the path.
* For a request whose `Host` resolves to a subdomain `Site`, it prefixes the
* request URL with the site's `baseRoutePrefix` — e.g. `/privacy` on
* `lineage.freno.me` becomes `/lineage/privacy` internally, exactly as the
* `vercel.json` rewrite intended — so the file router resolves the correct
* subdomain route file (`src/routes/lineage/privacy.tsx`).
*
* The browser URL is untouched (this is an internal rewrite, not a
* redirect). `useLocation()` will report the prefixed internal path; the
* canonical-URL derivation in `src/components/page-head-meta.ts` strips the
* prefix so the public canonical stays `https://lineage.freno.me/privacy`.
*
* ## Scope / skip conditions
*
* - Main site / unknown host → no rewrite (no prefix to add).
* - `/api/*` → shared API pool (already routed correctly on all hosts; the
* `vercel.json` `/api/(.*)` rules are pure pass-throughs, so no prefix).
* - Paths already carrying a subdomain prefix (dev path-based URLs like
* `localhost:3000/lineage/privacy`, or a request already rewritten) → no
* double-prefix.
* - `/_build/*` build assets → served statically, not routed.
*
* ## Dev vs prod
*
* In dev, the Host is usually `localhost` (→ main → no rewrite); subdomain
* pages are reached via their path prefix (`localhost:3000/lineage/privacy`)
* which the skip-condition above leaves untouched. Dev subdomains reached
* via `lineage.localhost:3000/privacy` (browsers resolve `*.localhost`) ARE
* rewritten, keeping dev and prod behavior consistent.
*/
import { resolveSiteFromHost } from "~/lib/site-context";
/**
* Minimal H3-event shape this middleware touches. Avoids importing
* `vinxi/http` (a type-only subpath that some environments can't resolve) —
* the real H3Event satisfies this structure at runtime.
*/
interface RewriteEvent {
node?: {
req?: {
url?: string;
originalUrl?: string;
headers?: { host?: string };
};
};
_path?: string;
}
export default {
onRequest(event: RewriteEvent) {
const req = event?.node?.req;
if (!req?.headers) return;
const site = resolveSiteFromHost(req.headers.host);
// No prefix to add for the main site / unknown host.
if (!site.baseRoutePrefix) return;
const url = req.url || "/";
// Shared API pool — pass through unchanged on every host.
if (url === "/api" || url.startsWith("/api/")) return;
// Already prefixed (dev path-based URLs, or a request already rewritten).
if (
url === site.baseRoutePrefix ||
url.startsWith(site.baseRoutePrefix + "/")
) {
return;
}
// Static build assets are served as files, not via the router.
if (url.startsWith("/_build/")) return;
// Internal rewrite: /privacy → /lineage/privacy (browser URL unchanged).
// H3's toWebRequest derives the URL from `originalUrl ?? event.path`, so
// we must set originalUrl too (not just _path/req.url) or the SolidStart
// router keeps seeing the unprefixed browser path.
const rewritten = site.baseRoutePrefix + url;
req.originalUrl = rewritten;
req.url = rewritten;
event._path = rewritten;
}
};