A human task is a component that involves a person interacting
with a service or another person.
The interaction can be initiated either by a person or by an automated
service. A service that is initiated by a person can be either an automated
implementation or a service that is provided by another person. A human task
that is invoked by an automated service can be replaced easily by an automated
implementation.
Tasks can be used to implement staff activities in business processes that
require human interactions, such as manual exception handling and approvals.
All other exception handling is modeled natively in Web Services Business
Process Execution Language (WS-BPEL, abbreviated to BPEL), by using faults
and fault handlers, or compensation.
The types of human tasks are as follows:
- Participating tasks
- Support Web-service-to-person interactions, which enable a person to implement
a service. For example, a participating task can be a staff activity in a
business process.
- Administrative tasks
- Administrative tasks are similar to participating tasks, except that they
are used by administrators to solve technical problems that occur in processes.
Administrative tasks support authorization and user interface settings for
starting or administering business processes and human activities. Currently,
administration tasks are only created and managed by Business Flow Manager.
- Originating tasks
- Support person-to-computer interactions, which enables people to create,
initiate, and start services through a graphical user interface. For example,
a user can start a business process, or send it an event by means of an originating
task.
- Purely human tasks
- Support person-to-person interactions, which enable a person to invoke
a task as though it were an originating task. This invoked task is then performed
by another person, who interacts with it as though it were a participating
task. Purely human tasks do not interact with business processes
or other Web services.
Who can interact with a task can be determined using one of the supported
staff directories. Work items are created for users who have a reason to view
or interact with the task.
The human task manager supports the following types of user registry:
- Lightweight Directory Access Protocol (LDAP) user registry
- WebSphere user registry
Escalations
An escalation is a course of action
that is executed when a task is not completed satisfactorily within a specific
period of time. For example, if tasks are not claimed or are not completed
within a defined time limit. You can specify one, or more, escalations for
a task. These escalations can be started either in parallel or as a chain
of escalations.
Escalations are initialized when the associated task
reaches a certain state in its lifecycle. After a well defined duration, the
task state is verified, and if it does not meet the modeled expectation, the
escalation action is invoked. The following escalations actions are supported:
- Work items are created for a set of users
- E-mails are sent to the designated recipients
- Notification events are sent to registered consumers