Avaya SAB User Manual page 62

Setting up a trigger
Certain types of event - including loggable events and Java exceptions - can be handled using
triggers. These are (typically short) alternative dialog flows that are run when the triggering event
occurs.
There are five types of trigger:
Exception - evaluated only when an exception occurs within a dialog flow
•
Before step validated - legacy feature - DO NOT USE
•
Before step runs - evaluated before the step
•
After step runs - evaluated after the step
•
Unhandled control - evaluated if the path required is not defined in the dialog flow.
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Triggers may be configured
as part of a flow, in the Trigger Modeler window. These triggers are used by default when any
•
triggering event occurs in that flow, if the step in which the event occurs does not specifically
handle triggers
as part of a step, in the Edit Step dialog box. Step-based triggers are specific to the particular
•
instance of the component and take priority over any global triggers.
Handling exceptions
If an exception occurs in a flow, and no Exception trigger has been defined, the flow will fail.
There are three ways handle an Exception trigger.
try the step again
•
skip over the offending step
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elegantly end the call
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To configure the flow either to try the step again or to skip over the step, it is necessary to include an
ExceptionFlowControlStep in the trigger dialog flow (see page 63). However, if the
ExceptionFlowControlStep is not defined, the flow will throw and unhandled exception and the caller
will hear the default error message defined by the Voice Stack that is being used.
To end the call elegantly, you must build a trigger dialog flow that hangs up the call and add a
TerminateStep at the end of the flow. This will instruct the runtime that the flow must end immediately
and the flow will not throw an unhandled exception.
Flow trigger
To set up a flow trigger:
1. Select the Trigger Modeler window.
2. Select the type of trigger you want to create (see list above).
3. Check Create. SAB opens a dialog window.
4. Build the alternative dialog flow. If the trigger being defined is an Exception trigger, ensure that the
dialog flow contains an ExceptionFlowControlStep (see below).
Speech Applications Builder Configurator User Guide • May 15, 2004 • page 62 of 116