femto113/node-ifconfig

exec ifconfig and parse results into nested objects

node-ifconfig

exec ifconfig and parse results into nested objects

Motivation

Much useful information about a systems network interfaces (including their physical MAC addresses) can be had via the ifconfig tool but its output format defies naive parsing approaches, so some custom code is warranted.

Install

This hasn't been published to npm yet, so for now you'll have to clone it

% git clone https://github.com/femto113/node-ifconfig.git
% cd node-ifconfig
% sudo npm link

Usage

The module's exports consist of a single function, which simply execs ifconfig and passes the parsed output to your method.

var ifconfig = require("ifconfig");

ifconfig(function (err, results) {
   console.log("%s", JSON.stringify(results, null, "  "));
});

will output something like

{
  "lo0": {
    "flags": "8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384",
    "options": "3<RXCSUM,TXCSUM>",
    "inet6": "::1 prefixlen 128",
    "inet": "127.0.0.1 netmask 0xff000000"
  },
  "en0": {
    "flags": "8823<UP,BROADCAST,SMART,SIMPLEX,MULTICAST> mtu 1500",
    "ether": "99:ff:99:42:4d:12",
    "media": "autoselect (<unknown type>)",
    "status": "inactive"
  },
  "en1": {
    "flags": "8863<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500",
    "options": "2b<RXCSUM,TXCSUM,VLAN_HWTAGGING,TSO4>",
    "ether": "41:7c:9f:14:56:8c",
    "inet6": "fe90::436c:8fff:fe12:567c%en1 prefixlen 64 scopeid 0x7",
    "inet": "10.0.0.140 netmask 0xffffff00 broadcast 10.0.0.255",
    "media": "autoselect (1000baseT <full-duplex>)",
    "status": "active"
  }
}

Behavior isn't well defined if something called ifconfig isn't in your path or it doesn't produce the expected output format when called with no arguments. So far tested only on Mac OS X.

Here's a slightly fancier example, which prints only the MAC addresses of the active interfaces:

var ifconfig = require("ifconfig");

ifconfig(function (err, results) {
   Object.keys(results).filter(function (key) {
     return results[key].status == 'active' && 'ether' in results[key];
   }).map(function (key) {
     return results[key].ether;
   }).forEach(function (mac) { console.log(mac); });
});