Count the tcp socket states from `ss(8)`

parse-ss.js

// Count the tcp socket states from `ss(8)`
// usage: `while [ 1 ]; do ss -tanp | node ~/parse-ss-localports.js; sleep 5; done`

var _ = require('underscore');

var FIELDS = { STATE: 0, RECVQ: 1, SENDQ: 2, LOCAL: 3, REMOTE: 4 };

function uniqueEphemeral(list) { 
  return _.uniq(list).filter(isEphemeral).length;
}

function isEphemeral(val) {
  // adjust as needed: on linux `cat /proc/sys/net/ipv4/ip_local_port_range`
  return val >= 32768 && val <= 61000;
}

function consumeData(str) {
  var stats = {
    states: {},
    localports: [], 
    remoteports: [] 
  };

  str.split('\n').forEach(function(line) {
    if (line.indexOf('State') === 0 || !line) return; // header or blank
    var fields = line.split(/\s+/);
    var state = fields[FIELDS.STATE];
    if (stats.states[state] === undefined) {
      stats.states[state] = 0;
    }
    stats.states[state] += 1;

    var local = fields[FIELDS.LOCAL].match(/:(\d+)$/);
    if (local) {
      stats.localports.push(parseInt(local[1], 10));
    } 

    var remote = fields[FIELDS.REMOTE].match(/:(\d+)$/);
    if (remote) {
      stats.remoteports.push(parseInt(remote[1], 10));
    } 
  });

  stats.localports = uniqueEphemeral(stats.localports);
  stats.remoteports = uniqueEphemeral(stats.remoteports); 

  console.log(new Date().toISOString(), JSON.stringify(stats));
}

process.stdin.resume();
process.stdin.setEncoding('utf8');

var data = '';
process.stdin.on('data', function (chunk) {
  data += chunk;
});

process.stdin.on('end', function () {
  consumeData(data);
});