dbus-native/bin/dbus-dissect.js

D-bus protocol implementation in native javascript

// simple script to monitor incoming/outcoming dbus messages
// needs a lot of cleanup but does the job

const net = require('net');
const abs = require('abstract-socket');
const through2 = require('through2');
const optimist = require('optimist');
const message = require('../lib/message');
const readLine = require('../lib/readline');

var sessionBusAddress = process.env.DBUS_SESSION_BUS_ADDRESS;
var m = sessionBusAddress.match(/abstract=([^,]+)/);

var isSystemBus = optimist.boolean(['system']).argv.system;

var address = isSystemBus ? '/var/run/dbus/system_bus_socket' : `\0${m[1]}`;

function waitHandshake(stream, prefix, cb) {
  readLine(stream, function(line) {
    console.log(prefix, line.toString());
    if (
      line.toString().slice(0, 5) === 'BEGIN' ||
      line.toString().slice(0, 2) === 'OK'
    ) {
      cb();
    } else {
      waitHandshake(stream, prefix, cb);
    }
  });
}

net
  .createServer(function(s) {
    var buff = '';
    var connected = false;

    var socket = isSystemBus ? net : abs;
    var cli = socket.connect(address);

    s.on('data', function(d) {
      if (connected) {
        cli.write(d);
      } else {
        buff += d.toString();
      }
    });
    connected = true;
    cli.write(buff);
    cli.pipe(s);

    var cc = through2();
    var ss = through2();

    // TODO: pipe? streams1 and streams2 here
    cli.on('data', function(b) {
      cc.write(b);
    });
    s.on('data', function(b) {
      ss.write(b);
    });

    waitHandshake(cc, 'dbus>', function() {
      message.unmarshalMessages(cc, function(message) {
        console.log('dbus>\n', JSON.stringify(message, null, 2));
      });
    });

    waitHandshake(ss, ' cli>', function() {
      message.unmarshalMessages(ss, function(message) {
        console.log(' cli>\n', JSON.stringify(message, null, 2));
      });
    });
  })
  .listen(3334, function() {
    console.log(
      'Server started. connect with DBUS_SESSION_BUS_ADDRESS=tcp:host=127.0.0.1,port=3334'
    );
  });