Serve static assets in Hugging Face adapter

scripts/serve-hf.mjs

@@ -1,13 +1,80 @@
 import { createServer } from "node:http";
+import { createReadStream } from "node:fs";
+import { stat } from "node:fs/promises";
+import { extname, join, normalize, sep } from "node:path";
+import { fileURLToPath } from "node:url";
 
 const port = Number(process.env.PORT ?? 7860);
 const host = process.env.HOST ?? "0.0.0.0";
+const clientDir = fileURLToPath(new URL("../dist/client/", import.meta.url));
 
 const { default: app } = await import("../dist/server/server.js");
 
+const contentTypes = {
+  ".css": "text/css; charset=utf-8",
+  ".js": "text/javascript; charset=utf-8",
+  ".svg": "image/svg+xml",
+  ".jpg": "image/jpeg",
+  ".jpeg": "image/jpeg",
+  ".png": "image/png",
+  ".webp": "image/webp",
+  ".ico": "image/x-icon",
+  ".json": "application/json; charset=utf-8",
+};
+
+function resolveStaticPath(pathname) {
+  if (!pathname.startsWith("/assets/") && pathname !== "/favicon.svg") {
+    return undefined;
+  }
+
+  const relativePath = normalize(decodeURIComponent(pathname).replace(/^\/+/, ""));
+  const filePath = join(clientDir, relativePath);
+  const clientRoot = clientDir.endsWith(sep) ? clientDir : `${clientDir}${sep}`;
+
+  if (!filePath.startsWith(clientRoot)) {
+    return undefined;
+  }
+
+  return filePath;
+}
+
+async function serveStaticAsset(req, res, pathname) {
+  const filePath = resolveStaticPath(pathname);
+  if (!filePath) return false;
+
+  try {
+    const fileStat = await stat(filePath);
+    if (!fileStat.isFile()) return false;
+
+    res.writeHead(200, {
+      "content-type": contentTypes[extname(filePath)] ?? "application/octet-stream",
+      "content-length": fileStat.size,
+      "cache-control": pathname.startsWith("/assets/")
+        ? "public, max-age=31536000, immutable"
+        : "public, max-age=3600",
+    });
+
+    if (req.method === "HEAD") {
+      res.end();
+      return true;
+    }
+
+    createReadStream(filePath).pipe(res);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
 const server = createServer(async (req, res) => {
   const origin = `http://${req.headers.host ?? `${host}:${port}`}`;
-  const request = new Request(new URL(req.url ?? "/", origin), {
+  const url = new URL(req.url ?? "/", origin);
+
+  if (await serveStaticAsset(req, res, url.pathname)) {
+    return;
+  }
+
+  const request = new Request(url, {
     method: req.method,
     headers: req.headers,
     body: req.method === "GET" || req.method === "HEAD" ? undefined : req,