对于任何对简洁感兴趣的人来说，这里有一些“一行程序”，它们不需要不是标准Node.js安装的一部分的插件/依赖项:

eth0的公共IPv4、IPv6地址为阵列:

var ips = require('os').networkInterfaces().eth0.map(function(interface) {
    return interface.address;
});

eth0的第一个公网IP地址(一般为IPv4):

var ip = require('os').networkInterfaces().eth0[0].address;

这是对已接受答案的修改，它不考虑vEthernet IP地址，如Docker等。

/**
 * Get local IP address, while ignoring vEthernet IP addresses (like from Docker, etc.)
 */
let localIP;
var os = require('os');
var ifaces = os.networkInterfaces();
Object.keys(ifaces).forEach(function (ifname) {
   var alias = 0;

   ifaces[ifname].forEach(function (iface) {
      if ('IPv4' !== iface.family || iface.internal !== false) {
         // Skip over internal (i.e. 127.0.0.1) and non-IPv4 addresses
         return;
      }

      if(ifname === 'Ethernet') {
         if (alias >= 1) {
            // This single interface has multiple IPv4 addresses
            // console.log(ifname + ':' + alias, iface.address);
         } else {
            // This interface has only one IPv4 address
            // console.log(ifname, iface.address);
         }
         ++alias;
         localIP = iface.address;
      }
   });
});
console.log(localIP);

这将返回一个类似192.168.2.169的IP地址，而不是10.55.1.1。

我使用的是Node.js 0.6.5:

$ node -v
v0.6.5

我是这样做的:

var util = require('util');
var exec = require('child_process').exec;

function puts(error, stdout, stderr) {
        util.puts(stdout);
}

exec("hostname -i", puts);

根据注释，以下是当前版本Node.js的工作原理:

var os = require('os');
var _ = require('lodash');

var ip = _.chain(os.networkInterfaces())
  .values()
  .flatten()
  .filter(function(val) {
    return (val.family == 'IPv4' && val.internal == false)
  })
  .pluck('address')
  .first()
  .value();

上面一个答案的注释缺少对values()的调用。看起来os.networkInterfaces()现在返回一个对象而不是数组。

下面的解决方案对我来说是可行的

const ip = Object.values(require("os").networkInterfaces())
        .flat()
        .filter((item) => !item.internal && item.family === "IPv4")
        .find(Boolean).address;

下面是一个允许你获取本地IP地址的变体(在Mac和Windows上测试):

var
    // Local IP address that we're trying to calculate
    address
    // Provides a few basic operating-system related utility functions (built-in)
    ,os = require('os')
    // Network interfaces
    ,ifaces = os.networkInterfaces();


// Iterate over interfaces ...
for (var dev in ifaces) {

    // ... and find the one that matches the criteria
    var iface = ifaces[dev].filter(function(details) {
        return details.family === 'IPv4' && details.internal === false;
    });

    if(iface.length > 0)
        address = iface[0].address;
}

// Print the result
console.log(address); // 10.25.10.147