Reads out a DHT22 sensor and publishes the data to a MQTT broker

readout.py

# Raspberry Pi Tips & Tricks - https://raspberrytips.nl

import Adafruit_DHT

humidity, temperature = Adafruit_DHT.read_retry(Adafruit_DHT.AM2302, 2)

#print temperature
humidity = round(humidity, 2)
temperature = round(temperature, 2)

if humidity is not None and temperature is not None:
        print '{0:0.1f}|{1:0.1f}'.format(temperature, humidity)
else:
        print ''

run.php

<?php

use Monolog\Handler\RotatingFileHandler;
use Monolog\Handler\StreamHandler;
use Monolog\Logger;
use unreal4u\MQTT\Application\Message;
use unreal4u\MQTT\Client;
use unreal4u\MQTT\Protocol\Connect;
use unreal4u\MQTT\Protocol\Connect\Parameters;
use unreal4u\MQTT\Protocol\Publish;

chdir(__DIR__ . '/../');
include 'vendor/autoload.php';

$uniqId = substr(uniqid('fbs' . mt_rand(0, 255), true), -8);

$logger = new Logger('fanBaseroomSensors');
$logger->pushHandler(new StreamHandler('php://stdout', Logger::DEBUG));
$logger->pushHandler(new RotatingFileHandler('logs/fanBaseroomSensors.log', 14, Logger::DEBUG));
$logger->info('Program start, reading python output', ['uniqId' => $uniqId]);

$parts = explode('|', shell_exec('/usr/bin/python readout.py'));
$temperature = (float)$parts[0];
$humidity = (float)trim($parts[1]);
$logger->debug('Readout ready', ['temperature' => $temperature, 'humidity' => $humidity]);

if ($humidity < 100) {
    $connectionParameters = new Parameters('fbs-' . $uniqId, '192.168.1.1');
    $connectionParameters->setUsername('xxxx');
    $connectionParameters->setPassword('xxxx');
    $connect = new Connect();
    $connect->setConnectionParameters($connectionParameters);
    $client = new Client();
    $client->sendData($connect);

    if ($client->isConnected()) {
        $logger->debug('Connected to broker, constructing and sending message');
        $temperatureMessage = new Message();
        $temperatureMessage->setTopicName('sensors/temperature/kelder');
        $temperatureMessage->setPayload((float)$parts[0]);
        $temperatureMessage->setRetainFlag(true);

        $humidityMessage = new Message();
        $humidityMessage->setTopicName('sensors/humidity/kelder');
        $humidityMessage->setPayload((float)trim($parts[1]));
        $humidityMessage->setRetainFlag(true);

        $publish = new Publish();
        $publish->setMessage($temperatureMessage);
        $client->sendData($publish);
        $logger->debug('Published', ['temperature' => (float)$parts[0]]);
        $publish->setMessage($humidityMessage);
        $client->sendData($publish);
        $logger->debug('Published', ['humidity' => (float)trim($parts[1])]);
    } else {
        $logger->critical('Could not connect to MQTT broker!');
    }
} else {
    $logger->warning('Values fall outside scope of acceptable values');
}

$logger->info('Program stop');