Simplify middleware (#33)

Author: jonatanklosko

README.md

@@ -93,7 +93,7 @@ $ bun add --dev tidewave
 
 Then, configure it:
 
-Create `pages/api/tidewave/[...all].ts` with:
+Create `pages/api/tidewave.ts` with:
 
 ```typescript
 import type { NextApiRequest, NextApiResponse } from 'next';
@@ -128,14 +128,8 @@ Then create (or modify) `middleware.ts` with:
 import { NextRequest, NextResponse } from 'next/server';
 
 export function middleware(req: NextRequest): NextResponse {
-  const { pathname } = req.nextUrl;
-
-  if (pathname === '/tidewave') {
-    return NextResponse.rewrite(new URL(`/api/tidewave/index`, req.url));
-  }
-
-  if (pathname.startsWith('/tidewave')) {
-    return NextResponse.rewrite(new URL(`/api${pathname}`, req.url));
+  if (req.nextUrl.pathname.startsWith('/tidewave')) {
+    return NextResponse.rewrite(new URL(`/api/tidewave`, req.url));
   }
 
   // Here you could add your own logic or different middlewares.

src/next-js.ts

@@ -53,6 +53,18 @@ export async function tidewaveHandler(
   return async function handler(req: NextApiRequest, res: NextApiResponse): Promise<void> {
     const origin = req.headers.host;
 
+    // Parse endpoint manually, rewrite doesn't populate query
+    const url = new URL(req.url ?? '', `http://${origin}`);
+    const segments = url.pathname.split('/').filter(Boolean);
+    const [_tidewave, endpoint] = segments;
+
+    // Note that this is the original request URL, not accounting for
+    // Next.js rewrite. We validate that the request targets /tidewave,
+    // rather than /api/tidewave.
+    if (!url.pathname.startsWith('/tidewave')) {
+      return res.status(404).json({ message: 'This route only works when accessed at /tidewave' });
+    }
+
     if (origin) {
       const [hostname, port] = origin.split(':');
       config.host = hostname ? hostname : config.host;
@@ -64,11 +76,6 @@ export async function tidewaveHandler(
     await connectWrapper(securityMiddleware)(req, res, next);
     await connectWrapper(bodyParser.json())(req, res, next);
 
-    // Parse endpoint manually, rewrite doesn't populate query
-    const url = new URL(req.url ?? '', `http://${origin}`);
-    const segments = url.pathname.split('/').filter(Boolean);
-    const [_tidewave, endpoint] = segments;
-
     if (req.method === 'GET' && endpoint === undefined) {
       return await respondTidewaveHTML(res, config);
     }