fix(site): stabilize media and notification runtime

tools/admin-server.mjs

@@ -1,4 +1,5 @@
 import { createServer } from "node:http";
+import { createReadStream } from "node:fs";
 import { mkdir, readFile, stat, writeFile } from "node:fs/promises";
 import { extname, join, normalize } from "node:path";
 import { fileURLToPath } from "node:url";
@@ -44,6 +45,30 @@ function send(res, status, body, contentType = "text/plain; charset=utf-8") {
   res.end(body);
 }
 
+function sendStream(req, res, status, stream, headers) {
+  res.writeHead(status, {
+    "cache-control": "no-store",
+    "accept-ranges": "bytes",
+    ...headers,
+  });
+
+  if (req.method === "HEAD") {
+    stream.destroy();
+    res.end();
+    return;
+  }
+
+  stream.on("error", () => {
+    if (!res.headersSent) {
+      send(res, 500, "Failed to read file");
+      return;
+    }
+
+    res.destroy();
+  });
+  stream.pipe(res);
+}
+
 function sendJson(res, status, payload) {
   send(res, status, `${JSON.stringify(payload, null, 2)}\n`, "application/json; charset=utf-8");
 }
@@ -314,7 +339,52 @@ async function serveStatic(req, res) {
     }
 
     const ext = extname(filePath);
-    send(res, 200, await readFile(filePath), MIME[ext] || "application/octet-stream");
+    const contentType = MIME[ext] || "application/octet-stream";
+    const range = req.headers.range;
+
+    if (range) {
+      const match = /^bytes=(\d*)-(\d*)$/.exec(range);
+
+      if (!match) {
+        res.writeHead(416, {
+          "cache-control": "no-store",
+          "content-range": `bytes */${fileStat.size}`,
+        });
+        res.end();
+        return;
+      }
+
+      const start = match[1] ? Number(match[1]) : 0;
+      const end = match[2] ? Number(match[2]) : fileStat.size - 1;
+
+      if (
+        !Number.isInteger(start) ||
+        !Number.isInteger(end) ||
+        start < 0 ||
+        end < start ||
+        start >= fileStat.size
+      ) {
+        res.writeHead(416, {
+          "cache-control": "no-store",
+          "content-range": `bytes */${fileStat.size}`,
+        });
+        res.end();
+        return;
+      }
+
+      const cappedEnd = Math.min(end, fileStat.size - 1);
+      sendStream(req, res, 206, createReadStream(filePath, { start, end: cappedEnd }), {
+        "content-type": contentType,
+        "content-length": cappedEnd - start + 1,
+        "content-range": `bytes ${start}-${cappedEnd}/${fileStat.size}`,
+      });
+      return;
+    }
+
+    sendStream(req, res, 200, createReadStream(filePath), {
+      "content-type": contentType,
+      "content-length": fileStat.size,
+    });
   } catch {
     send(res, 404, "Not found");
   }