DNS

import * as dns from "node:dns";

const addrs = await dns.promises.resolve4("bun.com", { ttl: true });
console.log(addrs);
// => [{ address: "172.67.161.226", ttl: 0 }, ...]

import { dns } from "bun";

dns.prefetch("bun.com", 443);

import { dns } from "bun";

const [{ address }] = await dns.lookup("example.com", { backend: "system" });

import { dns } from "bun";

dns.prefetch("my.database-host.com", 5432);

dns.prefetch(hostname: string, port?: number): void;

import { dns } from "bun";

dns.prefetch("bun.com", 443);
//
// ... 过一段时间 ...
await fetch("https://bun.com");

{
  cacheHitsCompleted: number; // 已完成的缓存命中次数
  cacheHitsInflight: number;  // 进行中的缓存命中次数
  cacheMisses: number;        // 缓存未命中次数
  size: number;               // DNS 缓存条目数
  errors: number;             // 连接失败次数
  totalCount: number;         // 总连接请求次数（包含缓存命中和未命中）
}

import { dns } from "bun";

const stats = dns.getCacheStats();
console.log(stats);
// => { cacheHitsCompleted: 0, cacheHitsInflight: 0, cacheMisses: 0, size: 0, errors: 0, totalCount: 0 }

BUN_CONFIG_DNS_TIME_TO_LIVE_SECONDS=5 bun run my-script.ts