Open Weather PHP caching proxy

index.php

<?
$origin = @$_SERVER['HTTP_ORIGIN'];

$lat = round(floatval($_GET['lat']),2);
$lon = round(floatval($_GET['lon']),2);

if($lat > 90 || $lat < -90 || $lon > 180 || $lon < -180 ) {
    die('Invalid coordinates' . $lat . 'x' . $lon);
}

$cacheFile = 'cache_' . $lat . '_' . $lon;
    

if(
    strpos($origin, "https://localhost") === 0 ||
    strpos($origin, "https://sonictruth") === 0 ||
    strpos($origin, "https://192.") === 0 ||
     strpos($origin, "https://10.") === 0
    ) {
    header("Access-Control-Allow-Methods: GET");
    header("Access-Control-Allow-Origin: " . $origin . "");
}


function request() {
    global $cacheFile, $lat, $lon;
    $_GET['appid'] = 'xxxxxx';
    $_GET['lat'] = $lat;
    $_GET['lon'] = $lon;
    $url = 
    "https://api.openweathermap.org/data/2.5/onecall?" . http_build_query($_GET) ;
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

    $output = curl_exec($ch);

    $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    http_response_code($httpcode);   
    if ($httpcode === 200) {
     file_put_contents($cacheFile , $output);
    }
    return $output;
}
clearstatcache();
$stat = @stat($cacheFile );

if($stat == false || ($stat && time() - $stat["mtime"] > 3000)) {
    echo request();
} else {
    echo file_get_contents($cacheFile ); 
}