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 factory = function (engineRequest, devicesInfo, avahiCommands, procUtils) {

        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, device, mac) {
            if (device.zeroconf_name !== zeroconfName) {
                console.info('DISCOVERY - (' + SERVICE_NAME + '): Zeroconf name successfully recovered for device %s: ' +
                    '%s', mac, zeroconfName);
                var resource = '/device/' + device.id;
                var name = {zeroconf_name: zeroconfName};
                engineRequest.send(resource, 'PUT', name);
            } else {
                console.debug('DISCOVERY - (' + SERVICE_NAME + '): Zeroconf name for device: %s is not ' +
                    'changed. [%s]', mac, zeroconfName);
            }
        }

        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 devicesInfo.get(mac).then(function (device) {
                    if (!device) {
                        console.info('DISCOVERY - (' + SERVICE_NAME + "): Ignoring missing device %s - most probably the device has been" +
                            " just discovered", mac);
                    } else {
                        procUtils.exec(avahiCommands.getHostResolveCmd(ip))
                            .then(function (res) {
                                update(parseResult(res), device, mac);
                            })
                            .catch(errorHandler).
                            finally(function () {
                                "use strict";
                                devicesInfo.setUpdateTimeToNow(device.mac, SERVICE_NAME);
                            });
                    }
                });
            }
        }

        return {
            resolve: resolve
        };
    }
    ;

module.exports.factory = factory;