SOAP server/client example in WSDL mode

organization.wsdl

<?xml version="1.0" encoding="UTF-8"?>
<definitions name="Organization"
             targetNamespace="urn:Organization"
             xmlns:tns="urn:Organization"
             xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/"
             xmlns:xsd="http://www.w3.org/2001/XMLSchema"
             xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/"
             xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"
             xmlns="http://schemas.xmlsoap.org/wsdl/">

    <message name="FilterRequest">
        <part name="params" type="xsd:string"/>
    </message>

    <message name="FilterResponse">
        <part name="result" type="xsd:string"/>
    </message>

    <message name="LoginRequest">
        <part name="login" type="xsd:string"/>
        <part name="password" type="xsd:string"/>
    </message>

    <message name="LoginResponse">
        <part name="result" type="xsd:string"/>
    </message>

    <portType name="FilterPort">
        <operation name="doFilter">
            <input message="tns:FilterRequest"/>
            <output message="tns:FilterResponse"/>
        </operation>
        <operation name="login">
            <input message="tns:LoginRequest"/>
            <output message="tns:LoginResponse"/>
        </operation>
    </portType>

    <binding name="FilterBinding" type="tns:FilterPort">
        <soap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>
        <operation name="doFilter">
            <soap:operation soapAction="urn:FilterAction"/>
            <input>
                <soap:body use="encoded" namespace="urn:Organization" encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
            </input>
            <output>
                <soap:body use="encoded" namespace="urn:Organization" encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
            </output>
        </operation>
        <operation name="login">
            <soap:operation soapAction="urn:LoginAction"/>
            <input>
                <soap:body use="encoded" namespace="urn:Organization" encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
            </input>
            <output>
                <soap:body use="encoded" namespace="urn:Organization" encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
            </output>
        </operation>
    </binding>

    <service name="WSDLService">
        <port name="FilterPort" binding="tns:FilterBinding">
            <soap:address location="http://localhost/api/wsdl/orgs/soap-server.php"/>
        </port>
    </service>
</definitions>

soap-client.php

<?
$client = new SoapClient( "http://localhost/wsdls/organization.wsdl", array( 'cache_wsdl' => WSDL_CACHE_NONE ) );
try {
  $responseLogin = $client->login( 'test_user', 'test_password' ); // call login() from .wsdl
  if($responseLogin == "success") { // if success
    $response = $client->doFilter( $params ); // call doFilter() from .wsdl
    ?>
      <pre><? print_r( $response ); ?></pre>
    <?
  }
} catch ( SoapFault $sf ) {
  echo $sf->getMessage();

// Full SoapFault message
//  echo '<pre>';
//  var_dump( $sf );
//  echo '</pre>';

// Analyze last request
//  $xml = $client->__getLastRequest();
//  echo $xml;
}
?>

soap-server.php

<?
ini_set( "soap.wsdl_cache_enabled", 0 );
ini_set( 'soap.wsdl_cache_ttl', 0 );

function login( $login, $password )
{
  return "some string";
}

function doFilter( $params )
{
  return "some string";
}

$server = new SoapServer( "organization.wsdl" );
$server->addFunction( "login" );
$server->addFunction( "doFilter" );
$server->handle();
?>

any idea why i would be getting this error? "looks like we got no XML document"
what should the generated response look like?