ajax.php

<?php
include("PachubeAPI/PachubeAPI.php");
include("config.php");

function getInfoscreenData($config) {
	
	// Try to see if there's some recent cached output available
	if (file_exists($config->cache) && (time() < filemtime($config->cache) + $config->cache_expire)) {

		// It is. Let's use that as our output.
		return json_decode(file_get_contents($config->cache),true);

	} else {

		// No recent cached output. We need to get it from Cosm
		$pachube = new PachubeAPI($config->api_key);

		// Get the feed from the Cosm API, as a json
		$json = $pachube->getFeed("json", $config->feed);

		$data = array();
		
		// iterate through all data streams to get the values we need
		foreach (json_decode($json)->datastreams as $datastream) {
			switch ($datastream->id) {
				case $config->temperature:
					$data["temperature"] = $datastream->current_value;
					break;
				case $config->power:
					$data["power"] = $datastream->current_value;
					break;
				case $config->door:
					$data["door"] = $datastream->current_value;
					break;
				case $config->devices:
					$data["devices"] = $datastream->current_value;
					break;
				case $config->members:
					$data["members"] = $datastream->current_value;
					$data["memberratio"] = "" . (round(($data["members"]/314931)*100,3));
					break;
				case $config->account:
					$data["account"] = $datastream->current_value;
					break;
				case $config->internet_up:
					$data["internet_up"] = $datastream->current_value;
					break;
				case $config->internet_down:
					$data["internet_down"] = $datastream->current_value;
					break;
				case $config->payback:
					$data["payback"] = $datastream->current_value;
					break;
			}
		}
		
		$data["mqtt"] = readMQTTData();

		// Write to cache
		$data["source"] = "cache";
		file_put_contents($config->cache, json_encode($data));
		
		// Return live output
		$data["source"] = "live";
		
		return $data;		
	}
}

/**
 * Parses the FHEM JSON tree and extract the devices and their state.
 */
function readMQTTData () {
	$mqttData = array();

	$json = json_decode(file_get_contents("http://infra.raumzeitlabor.de/fhem?cmd=jsonlist&XHR=1"));

	foreach ($json->Results as $result) {
		if ($result->list == "PCA301") {
			foreach ($result->devices as $device) {
				$mqttData[] = array(
					"alias" => $device->ATTR->alias,
					"state" => $device->STATE);
			}
		}
	}

	return $mqttData;	
}	

$config = new Configuration();
readMQTTData();
if(realpath(__FILE__) == realpath($_SERVER['SCRIPT_FILENAME'])) {
	// Send header
	header('Cache-Control: no-cache, must-revalidate');
	header('Expires: Mon, 19 Jul 1997 00:00:00 GMT');
	header('Content-type: application/json');

	// Send output
	echo json_encode(getInfoscreenData($config));
}
?>