domotz-remote-pawn/src/discovery/avahi/resolve.js

Domotz Agent

/** This file is part of Domotz Agent.
 * Copyright (C) 2016  Domotz Ltd
 *
 * Domotz Agent is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Domotz Agent is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Domotz Agent.  If not, see <http://www.gnu.org/licenses/>.

 * Created by tom on 19/12/15.
 */

const RESOLVE_REG_EXP = /^(.*).local.$/i;
const SERVICE_NAME = 'AVAHI_RESOLVE';

var nameByMac = {};
var factory = function (engineRequest, devicesInfo, avahiCommands, procUtils) {
    var q = require('q');

    function errorHandler(err) {
        if (err.code === 9) {
            console.verbose('AVAHI_RESOLVE: Avahi Discovery: Timeout Reached');
        } else {
            console.debug(err.toString('utf8'));
        }
    }

    function parseResult(res) {
        var str = res.trim();
        var matches = str.match(RESOLVE_REG_EXP);
        return matches[1];
    }

    function update(zeroconfName, mac) {
        if (nameByMac[mac] !== zeroconfName && zeroconfName !== undefined) {
            console.info('DISCOVERY - (' + SERVICE_NAME + '): Zeroconf name successfully recovered for device %s: ' + '%s', mac, zeroconfName);
            var resource = '/subnet/ip/device/' + mac + '/zeroconf-name';
            var name = { zeroconf_name: zeroconfName };
            engineRequest
                .sendWithPromise(resource, 'PUT', name)
                .then(function () {
                    'use strict';
                    console.debug('DISCOVERY - (' + SERVICE_NAME + '): Old name for device [%s] was %s', mac, nameByMac[mac]);
                    nameByMac[mac] = zeroconfName;
                    console.debug('DISCOVERY - (' + SERVICE_NAME + '): Storing name %s for device [%s]', nameByMac[mac], mac);
                })
                .catch(function () {
                    console.error('Error reporting zeroconf name');
                });
        } else {
            console.debug('DISCOVERY - (' + SERVICE_NAME + '): Zeroconf name for device: %s is not changed. [%s]', mac, nameByMac[mac]);
        }
    }

    function resolve(dev) {
        var mac = dev.mac;
        var ip = dev.ip;
        if (devicesInfo.isToBeUpdated(mac, SERVICE_NAME)) {
            console.debug('DISCOVERY - (' + SERVICE_NAME + '): Resolving zeroconf name for device with IP: ' + ip + ' and MAC: ' + mac);

            return procUtils
                .exec(avahiCommands.getHostResolveCmd(ip))
                .then(function (res) {
                    update(parseResult(res), mac);
                })
                .catch(errorHandler)
                .finally(function () {
                    'use strict';
                    devicesInfo.setUpdateTimeToNow(mac, SERVICE_NAME);
                });
        } else {
            return q();
        }
    }

    return {
        resolve: resolve,
    };
};
module.exports.factory = factory;