Initial commit

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/instrumentation-node.ts

@@ -0,0 +1,32 @@
+import dns from "node:dns";
+
+/**
+ * Node-only：强制优先 / 仅用 IPv4，避免 Cloudflare AAAA ENETUNREACH
+ * 与 Happy Eyeballs 并行试 IPv6 时刷 AggregateError。
+ */
+dns.setDefaultResultOrder("ipv4first");
+
+const nativeLookup = dns.lookup.bind(dns) as (
+  hostname: string,
+  options?: unknown,
+  callback?: unknown,
+) => unknown;
+
+// dns.lookup 重载签名在不同 @types/node 版本间不一致，这里按运行时重载包装。
+dns.lookup = ((hostname: string, options?: unknown, callback?: unknown) => {
+  if (typeof options === "function") {
+    return nativeLookup(hostname, { family: 4 }, options);
+  }
+  if (typeof callback === "function") {
+    const opts =
+      typeof options === "number"
+        ? { family: 4 }
+        : { ...(options as object | undefined), family: 4 };
+    return nativeLookup(hostname, opts, callback);
+  }
+  const opts =
+    typeof options === "number"
+      ? { family: 4 }
+      : { ...(options as object | undefined), family: 4 };
+  return nativeLookup(hostname, opts);
+}) as typeof dns.lookup;