BPEL HUMAN WORKFLOW 11g Tutorial

In SOA 10g, human workflow is an independent component. It had to be deployed and configured separately. In SOA 11g, it’s tightly integrated with other components through the SCA architecture. The main components of SOA 11g human workflow are shown in the following figure.  On the left are the workflow initiators (typically BPEL or a mediator). However, the Human Task component is also exposed as a SOAP service that can be invoked independently. In the middle is the core human workflow component that is formed by a combination of workflow services. We will discuss about these services later. On the right, there are the client applications that present the user the necessary web (or another) interfaces to act on the task.

• BPEL invokes human task component when a manual task needs to be performed

• A task is created in the Human Task service component. (The task metadata is used by the component to manage lifecycle of the task)

• The Human task service component identifies the necessary users/roles/groups using an identity service and assigns the task

• These tasks are presented to the user through the client apps. (Oracle BPM worklist is the default app)

Human workflow Features

Here is a list of features that are supported by human workflow.  (http://docs.oracle.com/cd/E23943_01/dev.1111/e10224/bp_introhwf_shared.htm#CIHGEFCI). 

• Human interactions with processes, including assignment and routing of tasks to the correct users or groups

• Deadlines, escalations, notifications, and other features required for ensuring the timely performance of a task (human activity)

• Presentation of tasks to end users through a variety of mechanisms, including a worklist application (Oracle BPM Worklist)

• Organization, filtering, prioritization, and other features required for end users to productively perform their tasks

• Reports, reassignments, load balancing, and other features required by supervisors and business owners to manage the performance of tasks

These descriptions are at 1000 foot level. The real question is what’s behind the curtain that’s providing these capabilities? Let’s dive into the human workflow architecture to understand the inner workings.

Architecture

At the core, the human workflow is made up of several workflow services that are orchestrated to provide the different capabilities. 

Service Name	Description
Task Service	Primary service that manages the lifecycle of a Task. This service is invoked by the BPEL to initiate a Task.
Task Routing Service	Task Routing, Assigning and escalations are taken care by this service
Task Query Service	Queries tasks based on several criteria. (Used by client apps)
Task Metadata Service	Provides metadata of the task
Identity Service	This service is part of security infrastructure of the weblogic server.
Notification Service	Sends notifications through User Messaging services
User Metadata Service	Maintains metadata about workflow users. (Vacations, preferences, delegation rules…)
Runtime Config Service	Manages metadata used by task service
Evidence service	Provides storage services for audit trail. Supports digital signatures.

  

The following figure shows how the different components of human workflow are tied together with SOA 11g infrastructure components.: