PHP and no Soap action header

Question

I'm trying to call a remote web service, within my company. For proprietary reasons I cannot provide the URL to the web service. The web service has a single function called getItemField. It is a small test service that I'm trying to run PHP against, the service description is as follows:

<definitions xmlns="http://schemas.xmlsoap.org/wsdl/" xmlns:apachesoap="http://xml.apache.org/xml-soap" xmlns:impl="http://www.oracle.com/ws/MyFirstWebService" xmlns:intf="http://www.oracle.com/ws/MyFirstWebService" xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:tns1="http://www.w3.org/1999/XMLSchema" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:wsdlsoap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.oracle.com/ws/MyFirstWebService">
<!--
WSDL created by Apache Axis version: 1.2alpha Built on Oct 23, 2007 (12:09:54 IST)
-->
<wsdl:types>
<schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="http://www.oracle.com/ws/MyFirstWebService">
<import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
<complexType name="ArrayOf_xsd_string">
<complexContent>
<restriction base="soapenc:Array">
<attribute ref="soapenc:arrayType" wsdl:arrayType="xsd:string[]"/>
</restriction>
</complexContent>
</complexType>
</schema>
</wsdl:types>
<message name="getItemFieldRequest">
<part name="args" type="impl:ArrayOf_xsd_string"/>
</message>
<message name="getItemFieldResponse">
<part name="getItemFieldReturn" type="soapenc:string"/>
</message>
<portType name="MyFirstWebService">
<operation name="getItemField" parameterOrder="args">
<input message="impl:getItemFieldRequest" name="getItemFieldRequest"/>
<output message="impl:getItemFieldResponse" name="getItemFieldResponse"/>
</operation>
</portType>
<binding name="MyFirstWebServiceSoapBinding" type="impl:MyFirstWebService">
<wsdlsoap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>
<operation name="getItemField">
<wsdlsoap:operation soapAction=""/>
<input name="getItemFieldRequest">
<wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://first" use="encoded"/>
</input>
<output name="getItemFieldResponse">
<wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" namespace="http://www.oracle.com/ws/MyFirstWebService" use="encoded"/>
</output>
</operation>
</binding>
<service name="MyFirstWebServiceService">
<port binding="impl:MyFirstWebServiceSoapBinding" name="MyFirstWebService">
<wsdlsoap:address location="http://myWebsite.com/services/MyFirstWebService"/>
</port>
</service>
</definitions>

I can connect to the service just fine and print out the name of the single function and type, but when I try to call a function I get 'no SOAPAction header!' error. My PHP code to call the service function is as follows:

$options = array(
                // Dev
                'soap_version'=>SOAP_1_2, 
                'exceptions'=>true, 
                'trace'=>1, 
                'cache_wsdl'=>WSDL_CACHE_NONE,
                'features' => SOAP_SINGLE_ELEMENT_ARRAYS,

                // Credentials
                'login' => 'user', 
                'password' => 'pass'
            );        

// Connected successfully
            $client = new SoapClient( "http://myWebsite.com/services/MyFirstWebService?wsdl", $options );

    //Params
        $params = array( '123456' );

        //Options
        $options = array( 'soapaction' => '""' );

        //Call function (Both methods below throw the same 'no SOAPAction header!' error)
        //$result = $client->getItemField( new SoapParam($params, "getItemFieldRequest") );
        $result = $client->__soapCall( "getItemField", array('123456'), $options );

Based on the description of the service it doesn't appear to have a soapaction defined. The line I see with soapAction is <wsdlsoap:operation soapAction=""/>. I tried to specify a blank soapAction since there's none defined, but that didn't seem to work. Is the web service definition itself incomplete? Or am I missing some parameter in my client-side application call? Thanks in advance.

UPDATE:

Tried to specify the method name as the soap action, but htat didn't work.

    //Params
    $params = array( '123456' );

    //Options
    $options = array( 'soapaction' => 'getItemField' );

    //Call function (STILL THROWS 'no SOAPAction header!')
    $result = $client->__soapCall( "getItemField", $params, $options );

What am I supposed to do if no soapAction is specified in the wsdl, i.e. if it's set to "".

Solution

I had a similar issue, but I was using cURL and not the SoapClient, though the solution may be the same.

When sending a request to the end service, you have to send a header specifying the Content-Type. In this header, you can also specify the action, or "soap action".

$headers = array();
$headers[] = 'Content-Type: application/soap+xml; charset=utf-8; action="[soap action goes here]"';
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

In my case, and what appears to be the same as yours, the wsdl lists the following:

<wsdl:operation name="getProducts">
    <soap:operation soapAction=""/>
    <!-- trimmed -->
</wsdl:operation>

At first, I see soapAction="", so I set action="" in the headers being sent. This failed. The correct data that goes into the header is the operation, making it action="getProducts".

Based on the manual for SoapClient and the answer to php using SOAP with a different SoapAction, your request should have worked with:

$client = new SoapClient( "http://myWebsite.com/services/MyFirstWebService?wsdl", $options );
$result = $client->__soapCall( "getItemField", array('123456') );

Did you ever omit the $options sent to __soapCall() to simply not specify an action (rather than passing in a blank one)?