[fix] workaround sirv bug

.changeset/tame-lions-jump.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/adapter-node': patch
+---
+
+[fix] workaround sirv bug to allow routes with unicode characters

packages/adapter-node/src/server.js

@@ -26,6 +26,17 @@ export function createServer({ render }) {
 		  })
 		: noop_handler;
 
+	// handle static assets with unicode characters
+	// e.g. a route with unicode character will generate a .js file with unicode character
+	// https://github.com/lukeed/sirv/issues/82#issuecomment-898618504
+	const sirv_workaround_handler = fs.existsSync(paths.assets)
+		? (req, _, next) => {
+				req._origPath = req.path;
+				req.path = decodeURI(req.path);
+				next();
+		  }
+		: noop_handler;
+
 	const assets_handler = fs.existsSync(paths.assets)
 		? sirv(paths.assets, {
 				setHeaders: (res, pathname, stats) => {
@@ -39,7 +50,16 @@ export function createServer({ render }) {
 		  })
 		: noop_handler;
 
+	const revert_sirv_workaround_handler = fs.existsSync(paths.assets)
+		? (req, _, next) => {
+				req.path = req._origPath;
+				next();
+		  }
+		: noop_handler;
+
 	const server = polka();
+	// workaround https://github.com/lukeed/polka/issues/142
+	// until https://github.com/lukeed/polka/pull/172 is merged and released
 	// Polka has a non-standard behavior of decoding the request path
 	// Disable it so that adapter-node works just like the rest
 	// SvelteKit will handle decoding URI components into req.params
@@ -48,7 +68,9 @@ export function createServer({ render }) {
 	};
 	server.use(
 		compression({ threshold: 0 }),
+		sirv_workaround_handler,
 		assets_handler,
+		revert_sirv_workaround_handler,
 		prerendered_handler,
 		async (req, res) => {
 			const parsed = new URL(req.url || '', 'http://localhost');