fix: respect LETTERFEED_BACKEND_URL at build time #1

frontend/src/middleware.ts

@@ -0,0 +1,18 @@
+import { NextRequest, NextResponse } from 'next/server';
+
+export function middleware(request: NextRequest) {
+  const backendUrl = process.env.LETTERFEED_BACKEND_URL || 'http://backend:8000';
+
+  if (request.nextUrl.pathname.startsWith('/api/')) {
+    const url = request.nextUrl.clone();
+    const path = url.pathname.replace('/api', '');
+    url.href = `${backendUrl}${path}${url.search}`;
+    return NextResponse.rewrite(url);
+  }
+
+  return NextResponse.next();
+}
+
+export const config = {
+  matcher: '/api/:path*',
+};