Creating a SOAP Server - PHP

Creating a SOAP server with the native SOAP extension is easier than you think. Although several server-specific methods are provided with the SOAP extension, only three methods are required to create a complete WSDL-enabled server. This section introduces these and other methods, guiding you through the process of creating a functional SOAP server as the section progresses. The section “SOAP Client and Server Interaction” offers a complete working example of the interaction between a WSDL-enabled client and server created using this extension. To illustrate this, the examples in the remainder of this chapter refer to Listing 20-6, which offers a sample WSDL file. Directly following the listing, a few important SOAP configuration directives are introduced that you need to keep in mind when building SOAP services using this extension.

Listing 20-6. A Sample WSDL File (boxing.wsdl)

    <message name="getQuoteRequest">
      <part name="boxer" type="xsd:string" />
    </message>

    <message name="getQuoteResponse">
      <part name="return" type="xsd:string" />
    </message>

    <portType name="QuotePortType">
      <operation name="getQuote">
        <input message="tns:getQuoteRequest" />
        <output message="tns:getQuoteResponse" /> 
      </operation>
    </portType>

    <binding name="QuoteBinding" type="tns:QuotePortType">
      <soap:binding
            style="rpc" transport="http://schemas.xmlsoap.org/soap/http" />
      <operation name="getQuote">
        <soap:operation soapAction="" />
          <input>
            <soap:body use="encoded" 
             encodingStyle="http:// schemas.xmlsoap.org/soap/encoding/" /> 
          </input>
          <output>
            <soap:body use="encoded"
            encodingStyle="http:// schemas.xmlsoap.org/soap/encoding/" /> 
          </output>
      </operation>
    </binding>

   <service name="boxing">
     <documentation>Returns quote from famous pugilists</documentation>
     <port name="QuotePort" binding="tns:QuoteBinding">
        <soap:address 
         location="http:// www.wjgilmore.com/boxingserver.php" />
     </port>
   </service>
</definitions>

TheSoapServer()constructor instantiates a new instance of theSoapServer class in WSDL or non-WSDL mode. Its prototype looks like this:

object SoapServer->SoapServer(mixed wsdl [, array options])

If you require WSDL mode, you need to assign thewsdl parameter the WSDL file’s location, or else set it toNULL. The optionaloptionsparameter is an array used to set the following options:

actor: Identifies the SOAP server as an actor, defining its URI.

encoding: Sets the character encoding.

soap_version: Determines the supported SOAP version and must be set with the syntax

SOAP_x_y, wherex is an integer specifying the major version number, andy is an integer specifying the corresponding minor version number. For example, SOAP version 1.2 would be assigned asSOAP_1_2.

The following example creates aSoapServer object referencing theboxing.wsdlfile:

$soapserver = new SoapServer("boxing.wsdl");

If the WSDL file resides on another server, you can reference it using a valid URI:

$soapserver = new SoapServer("http://www.example.com/boxing.wsdl");

Next, you need to export at least one function, a task accomplished using theaddFunction()method, introduced next.

Note  If you’re interested in exposing all methods in a class through the SOAP server, use the methodsetClass(), introduced later in this section.