IBM BPM, V8.0.1, All platforms > Programming IBM BPM > Developing using the web service API

Web API and external implementations

IBM BPM includes a sample external implementation that illustrates how to use IBM BPM web API operations when developing a custom application to enable process participants to complete a particular step within a process instance.

You can use external implementations to create your own implementation of a service that is invoked as part of the process. When you do this, you have access to the process context and this access is provided by the web API.

When a process instance reaches a step handled by an external implementation, the process server does not invoke the custom application. Instead, after passing all necessary process data to the custom application, the process server ceases its work on the process instance. When the custom application completes, the process server resumes its work on the process instance, using any updated process data received from the custom application.

Sample

You can find the source files for a sample external implementation in [BPM_install_directory]\BPM\Lombardi\web-api\samples\eclipse. The sample external implementation is a custom Eclipse application that enables managers to either approve or reject expense reports from their employees. It represents one step in a process and can be modeled as an external implementation in Process Designer.

You can also import the sample BPD External Implementation Library, and other associated components in the ExpenseApproval.twx file from [BPM_install_directory]\BPM\Lombardi\web-api\samples\imports. The sample Eclipse application combined with the corresponding library items provide a complete working example of external implementations.

Developing using the web service API

Related reference:
Setting the start time for an external implementation