Selecting the service port with PHP's SoapClient

I’m currently integrating with a SOAP service which has two different services defined.

The relevant part of the WSDL is:

<wsdl:service name="Config">
    <wsdl:port name="BasicHttpBinding_IConfiguration" binding="tns:BasicHttpBinding_IConfiguration">
        <soap:address location="http://nonsecure.example.com/Configuration.svc"/>
    </wsdl:port>
    <wsdl:port name="BasicHttpsBinding_IConfiguration" binding="tns:BasicHttpsBinding_IConfiguration">
        <soap:address location="https://secure.example.com/Configuration.svc"/>
    </wsdl:port>
</wsdl:service>

I discovered that PHP’s SoapClient will select the first port it encounters and doesn’t provide a way to select another one. This was a nuisance as I wanted to use the SSL one.

Through research, I discovered that I can use __setLocation():

$client->__setLocation('https://secure.example.com/Configuration.svc');

However, I don’t control that endpoint, so I would rather select based on the port’s name.

As I couldn’t find a way to get the data from SoapClient, I decided to parse the WSDL myself and pull the information out. I don’t do a lot with XML namespaces, so had to look up how to handle them and then how to extract the right data using XPath.

As I had to look it up, I’m putting it here, so I can find it again more easily!

I converted my new found knowledge into a method to extract the location attribute from the <soap:address> element of the <wsdl:port> with the correct name element:

function getLocationForPort($wsdl, $portName)
{
    $file = file_get_contents($wsdl);

    $xml = new SimpleXmlElement($file);

    $query = "wsdl:service/wsdl:port[@name='$portName']/soap:address";
    $address = $xml->xpath($query);
    if (!empty($address)) {
        $location = (string)$address[0]['location'];
        return $location;
    }

    return false;
}

Xpath is ideal for this job!

Usage is simply:

$client = new SoapClient($wsdl);
$sslLocation = getLocationForPort($wsdl, 'BasicHttpsBinding_IConfiguration');
if ($sslLocation) {
    $client->__setLocation($location);
}
// work with $client as normal

Now, all my calls to the SOAP service are via SSL as they should be!