Using Web Services (SAP Library - WebFlow Engine (BC-BMT-WFM))

Using Web Services

Purpose

You can execute your own and external Web services from a workflow. These Web services can require a dialog with a user or be executed in the background. The execution of a Web service can take place asynchronously or synchronously. When execution is asynchronous, the Web service is called and the workflow system transfers a callback address to the Web service, to which the Web service can send a confirmation or a result after execution is completed. When execution is synchronous, the workflow system waits until the Web service sends a result. A Web service can either send just a confirmation that was executed, or also a result in the form of parameters.

The workflow system supports the following types of Web services:

Type	Interaction	Result	Example
Dialog	Asynchronous	No	Search in a search engine
Dialog	Asynchronous	Yes	Reserving a hotel room
Background	Synchronous	Yes	Sending an SMS
Background	Asynchronous	Yes	Sending an SMS and waiting for a confirmation of receipt

The entry No in the result column means that the workflow system cannot process inbound result parameters of the Web service.

Prerequisites

You must know the definition of the Web services that you want to use. You can either use Web services available in the Internet or in an intranet, or create Web services yourself in the SAP Web Application Server.

For example, you can create dialog orientated Web services as a BSP application. For more information, see Creation of Web Application with BSPs.

Web services that run in the background must support the IF_HTTP_EXTENSION interface. For more information, see HTTP Request Handler.

Process Flow

To be able to use Web services with the workflow system, you have to execute the following steps.

Prepare the workflow system to use Web services. This step must only be executed once. For more information, see Configure Workflow System for the Use of Web Services.

Registration of the Web services that you want to use in a Web service directory. You can register the Web service manually. For this, add the relevant URL of the Web service, its interface, and the port. Or you can also import this data from a WSDL file if you have this for the Web service. For more information, see Register Web Service Definition.

You can create a task for registered Web services that you can include in your workflow as an activity. The interface of the Web Service is mapped in the task container. For more information, see Use Web Service in Workflow.