IBM BPM, V8.0.1, All platforms > Programming IBM BPM > Developing client applications for BPEL processes and tasks > Developing web services API client applications > Publishing and exporting artifacts from the server environment

Export WSDL and XSD files for BPEL process and human task web services applications

BPEL processes and human tasks have well-defined interfaces that allow them to be accessed externally as web services. You need to export the WSDL interface definitions and the XML Schema data type definitions to your client programming environment.

This topic applies to the following Business Process Choreographer web services interfaces:

• HTTP transport layer
• JMS transport layer

This procedure must be repeated for each BPEL process or human task that your client application needs to interact with.

For example, to create and start a human task, the following items of information must be passed to the task interface:

• The task template name

• The task template namespace

• An input message, containing formatted business data

• A response wrapper for returning the response message

• A fault message for returning faults and exceptions

These items are encapsulated within a single business object. All operations of the web service interface are modeled as a document/literal wrapped operation. Input and output parameters for these operations are encapsulated in wrapper documents. Other business objects define the corresponding response and fault message formats.

In order to create and start the BPEL process or human task through a web service, these wrapper objects must be made available to the client application on the client side.

This is achieved by exporting the business objects from the WebSphere environment as Web Service Definition Language (WSDL) and XML Schema Definition (XSD) files, and importing the data type definitions into your client programming environment.

Procedure

1. Launch the IBM Integration Designer Workspace if it is not already running.

2. Select the Library module containing the business objects to be exported. A Library module is a compressed file that contains the necessary business objects.
3. Export the Library module.

4. Copy the exported files to your client application development environment.

Example

Assume a BPEL process exposes the following web service operation:

<wsdl:operation name="updateCustomer">
    <wsdl:input message="tns:updateCustomerRequestMsg" 
                name="updateCustomerRequest"/>
    <wsdl:output message="tns:updateCustomerResponseMsg" 
                 name="updateCustomerResponse"/>
    <wsdl:fault message="tns:updateCustomerFaultMsg" 
                name="updateCustomerFault"/>
  </wsdl:operation>

with the WSDL messages defined as:

<wsdl:message name="updateCustomerRequestMsg">  
    <wsdl:part element="types:updateCustomer" 
               name="updateCustomerParameters"/> 
  </wsdl:message>
  <wsdl:message name="updateCustomerResponseMsg">
    <wsdl:part element="types:updateCustomerResponse" 
               name="updateCustomerResult"/> 
  </wsdl:message>
  <wsdl:message name="updateCustomerFaultMsg">
    <wsdl:part element="types:updateCustomerFault" 
               name="updateCustomerFault"/> 
  </wsdl:message>

The concrete customer-defined elements types:updateCustomer, types:updateCustomerResponse, and types:updateCustomerFault must be passed to and received from the web services APIs using UserData parameters in all generic operations (call, sendMessage, and so on) performed by the client application.

The customer-defined elements are created, serialized and deserialized on the client application side using classes generated using the exported XSD files. The generation of these classes is part of the web service proxy generation where the exported WSDL and XSD files are included.

The generic operations of the web service interface propagate the document wrapper element to and from the operation that is implemented by the BPEL process or human task. For the sample operation in the previous example, a web service SOAP message might look as follows:

<soapenv:Envelope xmlns:soapenv="..." ...>
  <soapenv:Header>
    ...
  </soapenv:Header>
  <soapenv:Body>
    <bfm:sendMessage 
         xmlns:bfm="http://www.ibm.com/xmlns/prod/websphere/business-process/services/7.0">
      <processTemplateName>customerProcessTemplate</processTemplateName>
      <portType xmlns:cns="http://example.com/customerProcess">cns:customerProcessPortType</portType>
      <operation>updateCustomer</operation>
      <input>
        <cns:updateCustomer xmlns:cns="http://example.com/customerProcess">
          <street>1600 Pennsylvania Avenue Northwest</street>
          <city>Washington, DC 20006</city>
        </cns:updateCustomer>
      </input>
    </bfm:sendMessage>
  </soapenv:Body>
</soapenv:Envelope>

Publishing and exporting artifacts from the server environment for web services client applications