update

package/node_modules/@npmcli/agent/lib/dns.js

@@ -0,0 +1,53 @@
+'use strict'
+
+const { LRUCache } = require('lru-cache')
+const dns = require('dns')
+
+// this is a factory so that each request can have its own opts (i.e. ttl)
+// while still sharing the cache across all requests
+const cache = new LRUCache({ max: 50 })
+
+const getOptions = ({
+  family = 0,
+  hints = dns.ADDRCONFIG,
+  all = false,
+  verbatim = undefined,
+  ttl = 5 * 60 * 1000,
+  lookup = dns.lookup,
+}) => ({
+  // hints and lookup are returned since both are top level properties to (net|tls).connect
+  hints,
+  lookup: (hostname, ...args) => {
+    const callback = args.pop() // callback is always last arg
+    const lookupOptions = args[0] ?? {}
+
+    const options = {
+      family,
+      hints,
+      all,
+      verbatim,
+      ...(typeof lookupOptions === 'number' ? { family: lookupOptions } : lookupOptions),
+    }
+
+    const key = JSON.stringify({ hostname, ...options })
+
+    if (cache.has(key)) {
+      const cached = cache.get(key)
+      return process.nextTick(callback, null, ...cached)
+    }
+
+    lookup(hostname, options, (err, ...result) => {
+      if (err) {
+        return callback(err)
+      }
+
+      cache.set(key, result, { ttl })
+      return callback(null, ...result)
+    })
+  },
+})
+
+module.exports = {
+  cache,
+  getOptions,
+}