File: http://svn.grimore.org/cool-iot/trunk/main.js -

#!/usr/bin/env nodejs
///////////////////////////////////////////////////////////////////////////
//  Copyright (C) Wizardry and Steamworks 2018 - License: GNU GPLv3      //
//  Please see: http://www.gnu.org/licenses/gpl.html for legal details,  //
//  rights of fair usage, the disclaimer and warranty conditions.        //
///////////////////////////////////////////////////////////////////////////
 
const Gpio = require('onoff').Gpio
const mqtt = require('mqtt')
const YAML = require('yamljs');
const winston = require('winston')
 
// Load configuration file.
const config = YAML.load('config.yml');
 
// Generate GPIO pins for configuration.
var COOL = {};
for(var i in config.GPIO) {
  if(!config.GPIO.hasOwnProperty(i))
    continue;
 
  if(config.GPIO[i] === -1)
    continue;
 
  COOL[i] = new Gpio(config.GPIO[i], 'out')
}
 
// Set up logger.
winston.add(winston.transports.File, {filename: config.log})
 
// Initiate connection to MQTT.
const client  = mqtt.connect(config.mqtt.url, {queueQoSZero: false})
 
client.on('connect', function () {
  winston.info('Connected to MQTT server')
  client.subscribe(config.mqtt.topic)
})
 
client.on('message', function (topic, message) {
  if(message.length === 0)
    return;
 
  // Remove any retained message.
  client.publish(topic, "", {retain: true})
 
  message.
  message = message.toString()
  winston.info('Received message: ' + message)
  if(!(message in config.GPIO)) {
    winston.warn('Request to toggle unknown GPIO: ' + message)
    return;
  }
 
  var pin = config.GPIO[message]
  if(pin === -1) {
    winston.warn('GPIO pin for "' + message + '" is not configured')
    return;
  }
 
  winston.info('Toggling pin ' + pin + ' for ' + message)
  COOL[message].write(1, (err) => {
    if(err) {
      winston.err('Unable to toggle pin ' + pin + ' error message received is: ' + err.message)
      return;
    }
 
    setTimeout(function() {
      winston.info('Toggled pin ' + pin + ' for ' + message)
      COOL[message].write(0)
    }, 1000)
  })
})