QueryLocation.php

<?php 

//gestisce la query Overpass di Openstreetmap 

include('settings.php');

function give_osm_data($lat,$lon)
{
	
	$around =AROUND; 				//Number of meters to calculate radius to search
	$max=MAX;						//max number of points to search
	$tag=TAG; 						//tag to search accoring to Overpass_API Query Language

	//inserire qui la query Overpass modificando i paramentri
	$query = 'node(around:'.$around.','.$lat.','.$lon.')['.$tag.'];out '.$max.';';
	 
	$context = stream_context_create( array('http' => array(
		'method'  => 'POST',
		'header' => array('Content-Type: application/x-www-form-urlencoded'), //comment out headers for attachment to app engine
		'content' => 'data=' . urlencode($query),
	)));
	$endpoint = 'http://overpass-api.de/api/interpreter';
	$json = file_get_contents($endpoint, false, $context);
	//echo $json;
	//var_dump(json_decode($json));

	if (false === $json) {
		$error = error_get_last();
		echo $error['message'];
		// throw new ClientException($error['message']);
	}
	//ritorno il dato
	return $json;
}

?>