Einfache Abfrage des API von luftdaten.info basierend auf http://fuerles.de/index.php/it-welt/10-iot/59-feinstaub-sensor-api-lesen

luftdatenapi.php

<?php

/**
 * Class LuftdatenApi
 */
class LuftdatenApi
{
    const BASE_URL = 'http://api.luftdaten.info/v1/sensor/';

    /**
     * @param int $sensorId
     * @return string
     */
    public static function pickValues($sensorId)
    {
        $jsonResponse = file_get_contents(self::BASE_URL . $sensorId);
        $response = json_decode($jsonResponse);
        $result = array_pop($response);
        /** @var array $sensorDataValues */
        $sensorDataValues = $result->sensordatavalues;
        $valueString = $sensorDataValues[0]->value_type . ': ' . $sensorDataValues[0]->value;
        if (array_key_exists(1, $sensorDataValues)) {
            $valueString .= ' ' . $sensorDataValues[1]->value_type . ': ' . $sensorDataValues[1]->value;
        }
        return $valueString;
    }
}

$tweet = LuftdatenApi::pickValues(1778) . ' ' . LuftdatenApi::pickValues(1777);
$tweet = str_replace(['temperature', 'humidity', 'P1', 'P2'], ['Temp', 'Hum', 'P10', 'P2.5'], $tweet);
echo $tweet;