SoapClient set custom HTTP Header

Try setting a stream context for the soap client:

$client = new SoapClient($webServiceURI, array(
    "exceptions" => 0, 
    "trace" => 1, 
    "encoding" => $phpInternalEncoding,
    'stream_context' => stream_context_create(array(
        'http' => array(
            'header' => 'SomeCustomHeader: value'
        ),
    )),
));

This answer is the proper way to do it in PHP 5.3+ SoapClient set custom HTTP Header

However, PHP 5.2 does not take all of the values from the stream context into consideration. To get around this, you can make a subclass that handles it for you (in a hacky way, but it works).

class SoapClientBackport extends SoapClient {
  public function __construct($wsdl, $options = array()){
    if($options['stream_context'] && is_resource($options['stream_context'])){
      $stream_context_options = stream_context_get_options($options['stream_context']);
      $user_agent = (isset($stream_context_options['http']['user_agent']) ? $stream_context_options['http']['user_agent'] : "PHP-SOAP/" . PHP_VERSION) . "\r\n";
      if(isset($stream_context_options['http']['header'])){
        if(is_string($stream_context_options['http']['header'])){
          $user_agent .= $stream_context_options['http']['header'] . "\r\n";
        }
        else if(is_array($stream_context_options['http']['header'])){
          $user_agent .= implode("\r\n", $stream_context_options['http']['header']);
        }
      }
      $options['user_agent'] = $user_agent;
    }
    parent::__construct($wsdl, $options);
  }
}

I ran into a situation where I had to provide a hash of all the text of the soap request in the HTTP header of the request for authentication purposes. I accomplished this by subclassing SoapClient and using the stream_context option to set the header:

class AuthenticatingSoapClient extends SoapClient {
    private $secretKey = "secretKeyString";
    private $context;

    function __construct($wsdl, $options) {
        // Create the stream_context and add it to the options
        $this->context = stream_context_create();
        $options = array_merge($options, array('stream_context' => $this->context));

        parent::SoapClient($wsdl, $options);
    }

    // Override doRequest to calculate the authentication hash from the $request. 

    function __doRequest($request, $location, $action, $version, $one_way = 0) {
        // Grab all the text from the request.
        $xml = simplexml_load_string($request);
        $innerText = dom_import_simplexml($xml)->textContent;

        // Calculate the authentication hash. 
        $encodedText = utf8_encode($innerText);
        $authHash = base64_encode(hash_hmac("sha256", $encodedText, $this->secretKey, true));

        // Set the HTTP headers.
        stream_context_set_option($this->context, array('http' => array('header' => 'AuthHash: '. $authHash)));

        return (parent::__doRequest($request, $location, $action, $version, $one_way)); 
    }       
}

Maybe someone searching will find this useful.

its easy to implement in nuSoap:

NUSOAP.PHP

add to class nusoap_base:

var additionalHeaders = array();

then goto function send of the same class

and add

foreach ($this->additionalHeaders as $key => $value) {
    $http->setHeader($key, $value);
}

somewhere around (just before)

$http->setSOAPAction($soapaction); (line 7596)

now you can easy set headers:

$soapClient = new nusoap_client('wsdl adress','wsdl');
$soapClient->additionalHeaders = array('key'=>'val','key2'=>'val');

The SoapClient::__soapCall method has an $input_headers argument, which takes an array of SoapHeaders.

You could also use Zend Framework's SOAP client, which provides an addSoapInputHeader convenience method.