Exception Flows

Events can be added to Appian Smart Services as exceptions. Exceptions are designed to allow you to automatically handle problems that might arise during process execution.

Design Considerations

  • Activities (Smart Services, Sub-Process activities, Script Tasks, and User Input tasks) accept intermediate events.
    • Events such as Rule Events and Timer Events do not accept intermediate events.
  • Error events are not currently supported as exception flow triggers.
  • Activity-Chaining cannot be configured on exception flows.
  • Other actions configured within an activity are skipped when an exception flow is taken.
  • Intermediate events are evaluated as soon as your process flow reaches the activity.
    • The user who starts a process receives an alert whenever an exception is triggered.
    • The triggers for intermediate events are evaluated upon activation of an activity. If the trigger is true, the activity is interrupted/cancelled, and the exception flow is activated.
    • On an unattended activity, the activity and the exception triggers are started at the same time. It is not possible to determine which one completes first. This applies to Rule Events (as well as any Timer Events that have met their schedule conditions prior to node activation).
    • Configuring the Exception Flow on the subsequent node in your process ensures that an exception rule is evaluated in proper sequence for an unattended node.
    • Configure a roll back of any actions taken by the previous activity, if you evaluate exception rules within a subsequent node.

Creating an Exception Flow

  • Double click the activity where you want to add the exception flow.
  • Click the Exceptions tab.
  • Click one of the following event types to use as a trigger.
  • When an exception event is added, the node changes in appearance in the following manner.
Event Name Event Marker
No Event Update document icon
Receive Message Receive message exception flow icon
Timer Timer exception flow icon
Rule Rule exception flow icon
Multiple Events (Appian Smart Services Only) Multiple exception flow icon

One or more events can be added to an activity. When an event is added, a marker representing the event appears on the border of the activity. To create an exception flow, connect the marker to a flow within the process model. The connection between the marker and the flow is shown in red, to indicate an (alternate) exception flow.

  • Although multiple events can be added, you can only configure one exception flow per activity. The execution of any of the events configured within the activity results in the same exception flow being taken.

All events configured within an activity are evaluated before it is executed. Should any of the events execute, the process activity is not executed. The normal flow is skipped and the exception flow is taken instead. When an exception flow is taken, the process initiator is sent a portal alert.

Activity-Chaining cannot be configured on Exception Flows.

See also: Activity-Chaining

Creating an Exception Flow

To create an exception flow, connect the marker (representing the events added to the activity) to a flow in the process model. The connection between the marker and the process flow is highlighted in red.