Consuming an XML-RPC Web service

[sukishan]

Consuming an XML-RPC Web service
Now that we have built a server, the next step is to develop a client to call our web service. First, we need to bring in the base class library and define a scalar variable called $amount and assign it a value of $15.00:


<?
include("xmlrpc.inc");
$amount="15.00";
Then we instantiate our XML-RPC client which will connect to our new server. The value of $amount is passed to the server using the xmlrpcmsg object:


$format=new xmlrpcmsg('taxcalc.onttax',
            array(new xmlrpcval($amount, "double")));
$client=new xmlrpc_client("/xmlrpc-server.php", "localhost", 80);
Once a connection is made, the request is sent to the server. The response, which corresponds to the sales tax calculation, is then passed along to $value. $value is then converted to a scalar variable and returned to the user. Of course there is no need to stop there, you can easily create a custom client which manipulates the data returned from the server:


$request=$client->send($format);
$value=$request->value();
print $value->scalarval();
?>
XML-RPC is a simple, effective method of transmitting XML data. It has been implemented in projects such as FreeNET, O'Reilly's Meerkat, Syndic8, the Google API and numerous other applications. For more information about XML-RPC, be sure to visit the official website at http://www.xmlrpc.com or read Programming Web Services with XML-RPC.