XML-RPC with the Incutio PHP Library

XMP-RPC stands for XML Remote Procedure Calling. It is a protocol for making and receiving procedure calls over the internet.
What this means is that different computers can use XML-RPC to "ask each other questions". Using XML-RPC is just like making a function call in PHP, only the computer that executes the function could be thousands of miles away.
With the Incutio XML-RPC Library, making and receiving XML-RPC requests is almost as simple as calling native PHP functions. Here's some sample code, which calls a function entitled "test.getTime" on our simple demonstration server:

$client = new IXR_Client('http://scripts.incutio.com/xmlrpc/simpleserver.php');
$client->query('test.getTime');
print $client->getResponse();
// Prints the current time, according to our web server

With error checking, the above code looks like this:

$client = new IXR_Client('http://scripts.incutio.com/xmlrpc/simpleserver.php');
if (!$client->query('test.getTime')) {
   die('An error occurred - '.$client->getErrorCode().":".$client->getErrorMessage());
}
print $client->getResponse();

You can also send arguments along with your queries:

$client = new IXR_Client('http://scripts.incutio.com/xmlrpc/simpleserver.php');
if (!$client->query('test.add', 4, 5)) {
   die('An error occurred - '.$client->getErrorCode().":".$client->getErrorMessage());
}
print $client->getResponse();
// Prints '9'

Arguments are not limited to simple values. You can send strings and arrays as well:

$client = new IXR_Client('http://scripts.incutio.com/xmlrpc/simpleserver.php');
if (!$client->query('test.addArray', array(3, 5, 7))) {
   die('An error occurred - '.$client->getErrorCode().":".$client->getErrorMessage());
}
print $client->getResponse();
// Prints '3 + 5 + 7 = 15'

Writing an XML-RPC server is simple as well. Here's the full code for simpleserver.php:

<?php

include('IXR_Library.inc.php');

/* Functions defining the behaviour of the server */

function getTime($args) {
    return date('H:i:s');
}

function add($args) {
    return $args[0] + $args[1];
}

function addArray($array) {
    $total = 0;
    foreach ($array as $number) {
        $total += $number;
    }
    return implode(' + ', $array).' = '.$total;
}

/* Create the server and map the XML-RPC method names to the relevant functions */

$server = new IXR_Server(array(
    'test.getTime' => 'getTime',
    'test.add' => 'add',
    'test.addArray' => 'addArray'
));

?>