commit d2b2f2ec890bd8b82a4ad2239e462367fc473d28
Author: Luk Lu <luk.lu@faronear.org>
Date:   Sun Jan 24 11:54:30 2021 +0800

    migrate from so.base/Network.js

diff --git a/.prettierrc.js b/.prettierrc.js
new file mode 100644
index 0000000..e001ecd
--- /dev/null
+++ b/.prettierrc.js
@@ -0,0 +1,16 @@
+/* 
+对 VSCode Prettier 有效；建议一直要有本配置文件，否则不同版本的 Prettier 的默认配置会不同，例如 TrailingComma
+对 VSCode Prettier Standard 无效，似乎是集成了不能修改的配置。
+*/
+module.exports = {
+  printWidth: 160, // default 80
+  tabWidth: 2, // default 2
+  useTabs: false,
+  semi: false, // default true
+  singleQuote: true, // default false
+  trailingComma: 'es5', // none (default in v 1.*), es5 (default in v2.0.0), all
+  bracketSpacing: true, // default true
+  jsxBracketSameLine: false, // default false
+  arrowParens: 'always', // avoid (default in v1.9.0), always (default since v2.0.0)
+  quoteProps: 'as-needed', // as-needed (default), consistent, preserve
+}
diff --git a/index.js b/index.js
new file mode 100644
index 0000000..5b10bf9
--- /dev/null
+++ b/index.js
@@ -0,0 +1,59 @@
+const os = require('os')
+const dns = require('dns')
+const util = require('util')
+
+module.exports = {
+  dn2ip: async function (host) {
+    // domain name 2 ip
+    if (typeof host === 'string' && host) {
+      var ip = await util
+        .promisify(dns.resolve)(host, 'A')
+        .catch(function (err) {
+          mylog.warn('WARNING : host cannot resolve to ip: ' + host)
+          return null
+        })
+      if (ip && /^\d+\.\d+\.\d+\.\d+$/.test(ip[0])) {
+        return ip[0]
+      }
+    }
+    return null
+  },
+  isPrivateIp: function (addr) {
+    return (
+      /^(::f{4}:)?10\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})$/i.test(addr) ||
+      /^(::f{4}:)?192\.168\.([0-9]{1,3})\.([0-9]{1,3})$/i.test(addr) ||
+      /^(::f{4}:)?172\.(1[6-9]|2\d|30|31)\.([0-9]{1,3})\.([0-9]{1,3})$/i.test(addr) ||
+      /^(::f{4}:)?127\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})$/i.test(addr) ||
+      /^(::f{4}:)?169\.254\.([0-9]{1,3})\.([0-9]{1,3})$/i.test(addr) ||
+      /^f[cd][0-9a-f]{2}:/i.test(addr) ||
+      /^fe80:/i.test(addr) ||
+      /^::1$/.test(addr) ||
+      /^::$/.test(addr)
+    )
+  },
+  getMyIp: function () {
+    var publicIp = null
+    var privateIp = null
+    var self = this
+    try {
+      var ifaces = os.networkInterfaces()
+      Object.keys(ifaces).forEach(function (ifname) {
+        ifaces[ifname].forEach(function (iface) {
+          if ('IPv4' === iface.family && iface.internal === false) {
+            //            console.log('ip='+iface.address)
+            if (self.isPrivateIp(iface.address)) {
+              privateIp = iface.address
+              //              console.log('privateIp='+privateIp)
+            } else {
+              publicIp = iface.address
+              //              console.log('publicIp='+publicIp)
+            }
+          }
+        })
+      })
+    } catch (e) {
+      console.log('ERROR in getMyIP(): ' + e.message)
+    }
+    return publicIp || privateIp
+  },
+}
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..98361aa
--- /dev/null
+++ b/package.json
@@ -0,0 +1,15 @@
+{
+  "name": "nettool",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://git.faronear.org/npm/nettool"
+  },
+  "author": "",
+  "license": "ISC"
+}