Access an external web service using SOAP

This sample shows how to make a SOAP request to an external service.

It is based on a working example, but it has been simplified so it is (somewhat) easier to follow. It therefore will not work "as is". Use it as a template to guide your own developments.

Sample WSDL

Here is the sample WSDL (Web Service Description Language) the code is based on:

<definitions xmlns="http://schemas.xmlsoap.org/wsdl/" 
  xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" 
  xmlns:http="http://schemas.xmlsoap.org/wsdl/http/" 
  xmlns:xs="http://www.w3.org/2001/XMLSchema" 
  xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/" 
  xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/" 
  xmlns:y="http://mydomain.com/calculator/" 
  xmlns:ns="http://mydomain.com/calculator/types/" 
  targetNamespace="http://mydomain.com/calculator/">
   <types>
     <xs:schema targetNamespace="http://mydomain.com/calculator/types/" 
       xmlns="http://mydomain.com/calculator/types/" 
       elementFormDefault="unqualified" attributeFormDefault="unqualified">
         <xs:complexType name="CalculatorInput">
            <xs:sequence>
               <xs:element name="x" type="xs:double"/>
               <xs:element name="y" type="xs:double"/>
            </xs:sequence>
         </xs:complexType>
         <xs:complexType name="CalculatorOutput">
            <xs:sequence>
               <xs:element name="result" type="xs:double"/>
            </xs:sequence>
         </xs:complexType>
         <xs:element name="Add" type="CalculatorInput"/>
         <xs:element name="AddResponse" type="CalculatorOutput"/>
      </xs:schema>
   </types>
   <message name="AddMessage">
      <part name="parameters" element="ns:Add"/>
   </message>
   <message name="AddResponseMessage">
      <part name="parameters" element="ns:AddResponse"/>
   </message>
   <portType name="CalculatorInterface">
      <operation name="Add">
         <input message="y:AddMessage"/>
         <output message="y:AddResponseMessage"/>
      </operation>
   </portType>
   <binding name="CalculatorSoapHttpBinding" type="y:CalculatorInterface">
      <soap:binding style="document" 
         transport="http://schemas.xmlsoap.org/soap/http"/>
      <operation name="Add">
         <soap:operation soapAction="http://mydomain.com/calculator/#Add"/>
         <input>
            <soap:body use="literal"/>
         </input>
         <output>
            <soap:body use="literal"/>
         </output>
      </operation>
   </binding>
   <service name="CalculatorService">
      <port name="CalculatorEndpoint" binding="y:CalculatorSoapHttpBinding">
         <soap:address location="http://mydomain.com/Calculator/Calculator.asmx"/>
      </port>
   </service>
</definitions>

Sample Code

Here is the code that uses that WSDL to access the remote service and connect to it. To use this code, you would place it into a Calculator class, and invoke the add() method from a Rule or from other platform code.

import com.platform.api.*;
import org.json.*;
import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;

public class Calculator
{
    // This method makes a request to the external web service to add two params
    public void add(Parameters p) throws Exception
    {
      // Here the parameters are assumed to be "x" and "y".
      // When you invoke a method in the platform, it will always be for some record.
      // The fields defined for that record are available in the Parameters object.
      // Use lines of code like these to extract them, for use in the SOAP request. 
      String x = (String)p.get("x");
      String y = (String)p.get("y");
      
      String soapRequest =
        "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"+
	"<SOAP-ENV:Envelope xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:soap=\"http://schemas.xmlsoap.org/wsdl/soap/\" xmlns:http=\"http://schemas.xmlsoap.org/wsdl/http/\" xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" xmlns:soapenc=\"http://schemas.xmlsoap.org/soap/encoding/\" xmlns:mime=\"http://schemas.xmlsoap.org/wsdl/mime/\" xmlns:y=\"http://mydomain.com/calculator/\" xmlns:ns=\"http://mydomain.com/calculator/types/\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\">"+
	"   <SOAP-ENV:Body>"+
	"      <mns1:Add xmlns:mns1=\"http://mydomain.com/calculator/\">"+
	"         <x>" + x + "</x>"+
	"         <y>" + y + "</y>"+
	"      </mns1:Add>"+
	"   </SOAP-ENV:Body>"+
	"</SOAP-ENV:Envelope>";
      
      // Create an HTTP connection to use for the SOAP request
      HttpConnection con = new HttpConnection(
          CONSTANTS.HTTP.METHOD.POST,
          "http://mydomain.com/Calculator/Calculator.asmx");
      
      con.addHeader("SOAPAction","http://mydomain.com/calculator/#Add");      
      con.addHeader("Content-Type","text/xml");
      con.setRequestBody(soapRequest);
      
      // Send the request and get the response
      int code = con.execute();
      String response = con.getResponse();

      /*********************************************
        Sample Response (as determined by the WSDL)

	<?xml version=\"1.0\" encoding=\"UTF-8\"?>
	<SOAP-ENV:Envelope xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:soap=\"http://schemas.xmlsoap.org/wsdl/soap/\" xmlns:http=\"http://schemas.xmlsoap.org/wsdl/http/\" xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" xmlns:soapenc=\"http://schemas.xmlsoap.org/soap/encoding/\" xmlns:mime=\"http://schemas.xmlsoap.org/wsdl/mime/\" xmlns:y=\"http://mydomain.com/calculator/\" xmlns:ns=\"http://mydomain.com/calculator/types/\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\">"+
	   <SOAP-ENV:Body>"+
	      <mns1:AddResponse xmlns:mns1=\"http://mydomain.com/calculator/\">
	         <result>1</result>
	      </mns1:AddResponse>
	   </SOAP-ENV:Body>
	</SOAP-ENV:Envelope>
      **********************************************/
 
      //Extract the result element from the response:
      // - First convert xml response to JSON using org.json package
      // - Then extract the result element
      JSONObject jo = org.json.XML.toJSONObject(response);	      
      String resultElement = jo.getJSONObject("SOAP-ENV:Envelope")
				.getJSONObject("SOAP-ENV:Body")
	    		  	.getJSONObject("mns1:AddResponse")
	    		  	.getString("result");
    }
}