SOAP API, How It Works

This document briefly describes usage of the SOAP workflow framework when developing a service consumer.

The below diagram illustrates how the SOAP calls can be implemented using workflow inProcess functionality:

The structure of the Request and Response is presented in the image below.

The SOAP layer remains unchanged for all SOAP calls, and each type of SOAP call is associated with the corresponding inProcess workflow.

RequestDTO contains the hookpointKey which identifies the associated workflow and array of ValueDTO objects. Each ValueDTO object contains the KEY and VALUE. Depending on the subclass used, VALUE can be long, String, double, Data or an array of ValueDTO objects.

The SOAP layer transforms the array of ValueDTO objects into the hash table of context objects with the corresponding keys provided in the request and starts the workflow with the hookpointKey provided in the request.

After the workflow is executed, the hash table with the result objects is passed back to the SOAP layer, which performs the transformation of the result hash table to ResponseDTO object, which is returned as a result of the SOAP call.

Getting Started

The first thing to do is to check the service end-point description page and WSDL document using the provided end-point address.

Usually the address of the end-point description page looks like this:

http://<host>:<port>/application-name/InvokerService

and the WSDL location like this:

http://<host>:<port>/application-name/InvokerService?wsdl

Accessing the end-point description page should display something like this:

and when it is attempted to access the WSDL location, the valid WSDL document should be displayed.

When you have the WSDL document, you can start generating the DTO classes. Many programming languages have their own tools for class generation from WSDL.

One of the easiest ways to do this in Java is to use JAX-WS and Maven with a plugin called jaxws-maven-plugin.

When you have successfully generated the class sources, you can start developing your service client using these classes and invoking the workflows.

The WSDL and data types XSD definitions:

WSDL

<?xml version='1.0' encoding='UTF-8'?><!-- Published by JAX-WS RI at http://jax-ws.dev.java.net. RI's version is JAX-WS RI 2.2.7b06  svn-revision#12863. --><!-- Generated by JAX-WS RI at http://jax-ws.dev.java.net. RI's version is JAX-WS RI 2.2.7b06  svn-revision#12863. -->
<definitions xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" xmlns:wsp="http://www.w3.org/ns/ws-policy" xmlns:wsp1_2="http://schemas.xmlsoap.org/ws/2004/09/policy" xmlns:wsam="http://www.w3.org/2007/05/addressing/metadata" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:tns="http://soap.CDRator.com/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://schemas.xmlsoap.org/wsdl/" targetNamespace="http://soap.CDRator.com/" name="InvokerService">
  <types>
    <xsd:schema>
      <xsd:import namespace="http://soap.CDRator.com/" schemaLocation="definition.xsd"/>
    </xsd:schema>
  </types>
  <message name="executeMethod">
    <part name="parameters" element="tns:executeMethod"/>
  </message>
  <message name="executeMethodResponse">
    <part name="parameters" element="tns:executeMethodResponse"/>
  </message>
  <portType name="InvokerService">
    <operation name="executeMethod">
      <input wsam:Action="http://soap.CDRator.com/InvokerService/executeMethodRequest" message="tns:executeMethod"/>
      <output wsam:Action="http://soap.CDRator.com/InvokerService/executeMethodResponse" message="tns:executeMethodResponse"/>
    </operation>
  </portType>
  <binding name="InvokerServicePortBinding" type="tns:InvokerService">
    <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/>
    <operation name="executeMethod">
      <soap:operation soapAction=""/>
      <input>
        <soap:body use="literal"/>
      </input>
      <output>
        <soap:body use="literal"/>
      </output>
    </operation>
  </binding>
  <service name="InvokerService">
    <port name="InvokerServicePort" binding="tns:InvokerServicePortBinding">
      <soap:address location="http://localhost:8080/simyo-workflow-soap/InvokerService"/>
    </port>
  </service>
</definitions>

definitions.xsd

<?xml version='1.0' encoding='UTF-8'?>
<!-- Published by JAX-WS RI at http://jax-ws.dev.java.net. RI's version is JAX-WS RI 2.2.7b06  svn-revision#12863. -->
  <xs:schema xmlns:tns="http://soap.CDRator.com/" xmlns:xs="http://www.w3.org/2001/XMLSchema" version="1.0" targetNamespace="http://soap.CDRator.com/">
    <xs:element name="executeMethod" type="tns:executeMethod"/>
    <xs:element name="executeMethodResponse" type="tns:executeMethodResponse"/>
    <xs:complexType name="executeMethod">
      <xs:sequence>
        <xs:element name="arg0" type="tns:requestDTO" minOccurs="0"/>
      </xs:sequence>
    </xs:complexType>
    <xs:complexType name="requestDTO">
      <xs:sequence>
        <xs:element name="hookpointKey" type="xs:string" minOccurs="0"/>
        <xs:element name="values" type="tns:valueDTO" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
    </xs:complexType>
    <xs:complexType name="valueDTO" abstract="true">
      <xs:sequence>
        <xs:element name="key" type="xs:string" minOccurs="0"/>
      </xs:sequence>
    </xs:complexType>
    <xs:complexType name="dateValueDTO">
      <xs:complexContent>
        <xs:extension base="tns:valueDTO">
          <xs:sequence>
            <xs:element name="value" type="xs:dateTime" minOccurs="0"/>
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
    <xs:complexType name="complexValueDTO">
      <xs:complexContent>
        <xs:extension base="tns:valueDTO">
          <xs:sequence>
            <xs:element name="value" type="tns:valueDTO" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
    <xs:complexType name="stringValueDTO">
      <xs:complexContent>
        <xs:extension base="tns:valueDTO">
          <xs:sequence>
            <xs:element name="value" type="xs:string" minOccurs="0"/>
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
    <xs:complexType name="longValueDTO">
      <xs:complexContent>
        <xs:extension base="tns:valueDTO">
          <xs:sequence>
            <xs:element name="value" type="xs:long"/>
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
    <xs:complexType name="doubleValueDTO">
      <xs:complexContent>
        <xs:extension base="tns:valueDTO">
          <xs:sequence>
            <xs:element name="value" type="xs:double"/>
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
    <xs:complexType name="booleanValueDTO">
      <xs:complexContent>
        <xs:extension base="tns:valueDTO">
          <xs:sequence>
            <xs:element name="value" type="xs:boolean"/>
          </xs:sequence>
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
    <xs:complexType name="executeMethodResponse">
      <xs:sequence>
        <xs:element name="return" type="tns:responseDTO" minOccurs="0"/>
      </xs:sequence>
    </xs:complexType>
    <xs:complexType name="responseDTO">
      <xs:sequence>
        <xs:element name="errorCode" type="xs:long"/>
        <xs:element name="errorMessage" type="xs:string" minOccurs="0"/>
        <xs:element name="status" type="xs:long"/>
        <xs:element name="values" type="tns:valueDTO" nillable="true" minOccurs="0" maxOccurs="unbounded"/>
      </xs:sequence>
    </xs:complexType>
  </xs:schema>

Assuming the workflow must be invoked which expects you to send the following structure:

Request:

Key	Value type	Mandatory	Description
CONTEXT	ComplexValueDTO	true	Context object, mandatory in each request.

CONTEXT:

Key	Value type	Mandatory	Description
LANGUAGE	StringValueDTO	true	Language code. EN, FR, DK, etc. Used for displaying error messages.
OPERATOR	StringValueDTO	true	Operator information.
BRAND_ID	StringValueDTO	false	Id of the brand if applicable.

then your client code would look something like this:

private static final String YOUR_HOOKPOINT_KEY = "YOUR_HOOKPOINT_KEY";
private static final String CONTEXT_KEY = "CONTEXT";
private static final String LANGUAGE_KEY = "LANGUAGE";
private static final String OPERATOR_KEY = "OPERATOR";

private static final String LANGUAGE_EN = "EN";
private static final String OPERATOR_DUMMY = "DUMMY";

<...>

public void invokeYourWorkflow() {
    InvokerService_Service service = new InvokerService_Service();
    InvokerService servicePort = service.getInvokerServicePort();

    RequestDTO request = new RequestDTO();

    request.setHookpointKey(YOUR_HOOKPOINT_KEY);

    StringValueDTO language = new StringValueDTO();
    language.setKey(LANGUAGE_KEY);
    language.setValue(LANGUAGE_EN);

    StringValueDTO operator = new StringValueDTO();
    language.setKey(OPERATOR_KEY);
    language.setValue(OPERATOR_DUMMY);

    ComplexValueDTO context = new ComplexValueDTO();
    context.setKey(CONTEXT_KEY);
    context.getValue().add(language);
    context.getValue().add(operator);

    request.getValues().add(context);

    ResponseDTO response = servicePort.executeMethod(request);
}

This approach gives a lot of flexibility as the changes to the service may be applied rapidly, it is just a matter of adding another DTO to a value list.

Note: You can also have a tree-like structure using ComplexValueDTO objects, i.e. you can have a list of ComplexValueDTO objects inside another ComplexValueDTO object. The example would look like this:

private static final String ROOT_KEY = "ROOT";

private static final String CHILD_ONE_KEY = "CHILD_ONE";

private static final String SUB_CHILD_ONE_KEY = "SUB_CHILD_ONE";
private static final String SUB_CHILD_TWO_KEY = "SUB_CHILD_TWO";

private static final String DUMMY_KEY = "DUMMY";
private static final String DUMMY_VALUE = "DUMMY"

<...>

public void doSomething() {
    <...>

    StringValueDTO dummy = new StringValueDTO();
    dummy.setKey(DUMMY_KEY);
    dummy.setValue(DUMMY_VALUE);

    ComplexValueDTO subChildOne = new ComplexValueDTO();
    subChildOne.setKey(SUB_CHILD_ONE_KEY);
    subChildOne.getValue().add(dummy);

    ComplexValueDTO subChildTwo = new ComplexValueDTO();
    subChildTwo.setKey(SUB_CHILD_TWO_KEY);
    subChildTwo.getValue().add(dummy);

    ComplexValueDTO childOne = new ComplexValueDTO();
    childOne.setKey(CHILD_ONE_KEY);
    childOne.getValue().add(subChildOne);
    childOne.getValue().add(subChildTwo);

    ComplexValueDTO root = new ComplexValueDTO();
    context.setKey(ROOT_KEY);
    context.getValue().add(childOne);

    <...>
}

<...>

This becomes useful when you have to transfer some kind of very complex object and pass it to the workflow framework.