Display HTTP headers in PHP.

http_headers.php

<?php
    $http_client_ip = '';
    $http_x_forwarded_for = '';
    $remote_addr = $_SERVER['REMOTE_ADDR'];
    $remote_host = '';
    $remote_port = $_SERVER['REMOTE_PORT'];
    $remote_user = '';
    $redirect_remote_user = '';
    $http_user_agent = $_SERVER['HTTP_USER_AGENT'];

    if (isset($_SERVER['HTTP_CLIENT_IP']))
    {
            $http_client_ip = $_SERVER['HTTP_CLIENT_IP'];
    }

    if (isset($_SERVER['HTTP_X_FORWARDED_FOR']))
    {
            $http_x_forwarded_for = $_SERVER['HTTP_X_FORWARDED_FOR'];
    }

    if (isset($_SERVER['REMOTE_HOST']))
    {
            $remote_host = $_SERVER['REMOTE_HOST'];
    }

    if (isset($_SERVER['REMOTE_USER']))
    {
            $remote_user = $_SERVER['REMOTE_USER'];
    }

    if (isset($_SERVER['REDIRECT_REMOTE_USER']))
    {
            $redirect_remote_user = $_SERVER['REDIRECT_REMOTE_USER'];
    }

    $api_url = 'http://api.hostip.info/get_html.php?ip='. $remote_addr .'&position=true';
    $response = file($api_url);
    foreach ($response as $line) {
            $line = trim($line);
            if (!empty($line)) {
                    $parts = explode(': ', $line);
                    $array[$parts[0]] = $parts[1];
            }
    }

    $country = $array['Country'];
    $city = $array['City'];
    $location = ($city == '(Unknown city)'? $country : $city .', '. $country);

    $lat = $array['Latitude'];
    $long = $array['Longitude'];
    $latlong = ((!empty($lat) && !empty($long))? $lat .','. $long : '');

    echo "HTTP_CLIENT_IP: ". $http_client_ip ."<br>";
    echo "HTTP_X_FORWARDED_FOR: ". $http_x_forwarded_for ."<br>";
    echo "REMOTE_ADDR: ". $remote_addr ."<br>";
    echo "REMOTE_HOST: ". $remote_host ."<br>";
    echo "REMOTE_PORT: ". $remote_port ."<br>";
    echo "REMOTE_USER: ". $remote_user ."<br>";
    echo "REDIRECT_REMOTE_USER: ". $redirect_remote_user ."<br>";
    echo "HTTP_USER_AGENT: ". $http_user_agent ."<br>";
    echo "LOCATION: ". $location ."<br>";
    echo "LAT/LONG: ". $latlong ."<br>";
?>