@Generated(value="software.amazon.awssdk:codegen") public final class Decision extends Object implements SdkPojo, Serializable, ToCopyableBuilder<Decision.Builder,Decision>
Specifies a decision made by the decider. A decision can be one of these types:
CancelTimer
– Cancels a previously started timer and records a TimerCanceled
event in the
history.
CancelWorkflowExecution
– Closes the workflow execution and records a
WorkflowExecutionCanceled
event in the history.
CompleteWorkflowExecution
– Closes the workflow execution and records a
WorkflowExecutionCompleted
event in the history .
ContinueAsNewWorkflowExecution
– Closes the workflow execution and starts a new workflow execution of
the same type using the same workflow ID and a unique run Id. A WorkflowExecutionContinuedAsNew
event is
recorded in the history.
FailWorkflowExecution
– Closes the workflow execution and records a WorkflowExecutionFailed
event in the history.
RecordMarker
– Records a MarkerRecorded
event in the history. Markers can be used for
adding custom information in the history for instance to let deciders know that they don't need to look at the
history beyond the marker event.
RequestCancelActivityTask
– Attempts to cancel a previously scheduled activity task. If the activity
task was scheduled but has not been assigned to a worker, then it is canceled. If the activity task was already
assigned to a worker, then the worker is informed that cancellation has been requested in the response to
RecordActivityTaskHeartbeat.
RequestCancelExternalWorkflowExecution
– Requests that a request be made to cancel the specified
external workflow execution and records a RequestCancelExternalWorkflowExecutionInitiated
event in the
history.
ScheduleActivityTask
– Schedules an activity task.
SignalExternalWorkflowExecution
– Requests a signal to be delivered to the specified external workflow
execution and records a SignalExternalWorkflowExecutionInitiated
event in the history.
StartChildWorkflowExecution
– Requests that a child workflow execution be started and records a
StartChildWorkflowExecutionInitiated
event in the history. The child workflow execution is a separate
workflow execution with its own history.
StartTimer
– Starts a timer for this workflow execution and records a TimerStarted
event in
the history. This timer fires after the specified delay and record a TimerFired
event.
Access Control
If you grant permission to use RespondDecisionTaskCompleted
, you can use IAM policies to express
permissions for the list of decisions returned by this action as if they were members of the API. Treating decisions
as a pseudo API maintains a uniform conceptual model and helps keep policies readable. For details and example IAM
policies, see Using IAM to
Manage Access to Amazon SWF Workflows in the Amazon SWF Developer Guide.
Decision Failure
Decisions can fail for several reasons
The ordering of decisions should follow a logical flow. Some decisions might not make sense in the current context of the workflow execution and therefore fails.
A limit on your account was reached.
The decision lacks sufficient permissions.
One of the following events might be added to the history to indicate an error. The event attribute's
cause
parameter indicates the cause. If cause
is set to
OPERATION_NOT_PERMITTED
, the decision failed because it lacked sufficient permissions. For details and
example IAM policies, see Using
IAM to Manage Access to Amazon SWF Workflows in the Amazon SWF Developer Guide.
ScheduleActivityTaskFailed
– A ScheduleActivityTask
decision failed. This could happen if
the activity type specified in the decision isn't registered, is in a deprecated state, or the decision isn't
properly configured.
RequestCancelActivityTaskFailed
– A RequestCancelActivityTask
decision failed. This could
happen if there is no open activity task with the specified activityId.
StartTimerFailed
– A StartTimer
decision failed. This could happen if there is another open
timer with the same timerId.
CancelTimerFailed
– A CancelTimer
decision failed. This could happen if there is no open
timer with the specified timerId.
StartChildWorkflowExecutionFailed
– A StartChildWorkflowExecution
decision failed. This
could happen if the workflow type specified isn't registered, is deprecated, or the decision isn't properly
configured.
SignalExternalWorkflowExecutionFailed
– A SignalExternalWorkflowExecution
decision failed.
This could happen if the workflowID
specified in the decision was incorrect.
RequestCancelExternalWorkflowExecutionFailed
– A RequestCancelExternalWorkflowExecution
decision failed. This could happen if the workflowID
specified in the decision was incorrect.
CancelWorkflowExecutionFailed
– A CancelWorkflowExecution
decision failed. This could
happen if there is an unhandled decision task pending in the workflow execution.
CompleteWorkflowExecutionFailed
– A CompleteWorkflowExecution
decision failed. This could
happen if there is an unhandled decision task pending in the workflow execution.
ContinueAsNewWorkflowExecutionFailed
– A ContinueAsNewWorkflowExecution
decision failed.
This could happen if there is an unhandled decision task pending in the workflow execution or the
ContinueAsNewWorkflowExecution decision was not configured correctly.
FailWorkflowExecutionFailed
– A FailWorkflowExecution
decision failed. This could happen if
there is an unhandled decision task pending in the workflow execution.
The preceding error events might occur due to an error in the decider logic, which might put the workflow execution in an unstable state The cause field in the event structure for the error event indicates the cause of the error.
A workflow execution may be closed by the decider by returning one of the following decisions when completing a
decision task: CompleteWorkflowExecution
, FailWorkflowExecution
,
CancelWorkflowExecution
and ContinueAsNewWorkflowExecution
. An
UnhandledDecision
fault is returned if a workflow closing decision is specified and a signal or activity
event had been added to the history while the decision task was being performed by the decider. Unlike the above
situations which are logic issues, this fault is always possible because of race conditions in a distributed system.
The right action here is to call RespondDecisionTaskCompleted without any decisions. This would result in
another decision task with these new events included in the history. The decider should handle the new events and may
decide to close the workflow execution.
How to Code a Decision
You code a decision by first setting the decision type field to one of the above decision values, and then set the corresponding attributes field shown below:
Modifier and Type | Class and Description |
---|---|
static interface |
Decision.Builder |
copy
public DecisionType decisionType()
Specifies the type of the decision.
If the service returns an enum value that is not available in the current SDK version, decisionType
will
return DecisionType.UNKNOWN_TO_SDK_VERSION
. The raw value returned by the service is available from
decisionTypeAsString()
.
DecisionType
public String decisionTypeAsString()
Specifies the type of the decision.
If the service returns an enum value that is not available in the current SDK version, decisionType
will
return DecisionType.UNKNOWN_TO_SDK_VERSION
. The raw value returned by the service is available from
decisionTypeAsString()
.
DecisionType
public ScheduleActivityTaskDecisionAttributes scheduleActivityTaskDecisionAttributes()
Provides the details of the ScheduleActivityTask
decision. It isn't set for other decision types.
ScheduleActivityTask
decision. It isn't set for other decision
types.public RequestCancelActivityTaskDecisionAttributes requestCancelActivityTaskDecisionAttributes()
Provides the details of the RequestCancelActivityTask
decision. It isn't set for other decision
types.
RequestCancelActivityTask
decision. It isn't set for other
decision types.public CompleteWorkflowExecutionDecisionAttributes completeWorkflowExecutionDecisionAttributes()
Provides the details of the CompleteWorkflowExecution
decision. It isn't set for other decision
types.
CompleteWorkflowExecution
decision. It isn't set for other
decision types.public FailWorkflowExecutionDecisionAttributes failWorkflowExecutionDecisionAttributes()
Provides the details of the FailWorkflowExecution
decision. It isn't set for other decision types.
FailWorkflowExecution
decision. It isn't set for other decision
types.public CancelWorkflowExecutionDecisionAttributes cancelWorkflowExecutionDecisionAttributes()
Provides the details of the CancelWorkflowExecution
decision. It isn't set for other decision types.
CancelWorkflowExecution
decision. It isn't set for other
decision types.public ContinueAsNewWorkflowExecutionDecisionAttributes continueAsNewWorkflowExecutionDecisionAttributes()
Provides the details of the ContinueAsNewWorkflowExecution
decision. It isn't set for other decision
types.
ContinueAsNewWorkflowExecution
decision. It isn't set for other
decision types.public RecordMarkerDecisionAttributes recordMarkerDecisionAttributes()
Provides the details of the RecordMarker
decision. It isn't set for other decision types.
RecordMarker
decision. It isn't set for other decision types.public StartTimerDecisionAttributes startTimerDecisionAttributes()
Provides the details of the StartTimer
decision. It isn't set for other decision types.
StartTimer
decision. It isn't set for other decision types.public CancelTimerDecisionAttributes cancelTimerDecisionAttributes()
Provides the details of the CancelTimer
decision. It isn't set for other decision types.
CancelTimer
decision. It isn't set for other decision types.public SignalExternalWorkflowExecutionDecisionAttributes signalExternalWorkflowExecutionDecisionAttributes()
Provides the details of the SignalExternalWorkflowExecution
decision. It isn't set for other
decision types.
SignalExternalWorkflowExecution
decision. It isn't set for other
decision types.public RequestCancelExternalWorkflowExecutionDecisionAttributes requestCancelExternalWorkflowExecutionDecisionAttributes()
Provides the details of the RequestCancelExternalWorkflowExecution
decision. It isn't set for other
decision types.
RequestCancelExternalWorkflowExecution
decision. It isn't set
for other decision types.public StartChildWorkflowExecutionDecisionAttributes startChildWorkflowExecutionDecisionAttributes()
Provides the details of the StartChildWorkflowExecution
decision. It isn't set for other decision
types.
StartChildWorkflowExecution
decision. It isn't set for other
decision types.public ScheduleLambdaFunctionDecisionAttributes scheduleLambdaFunctionDecisionAttributes()
Provides the details of the ScheduleLambdaFunction
decision. It isn't set for other decision types.
ScheduleLambdaFunction
decision. It isn't set for other decision
types.public Decision.Builder toBuilder()
ToCopyableBuilder
toBuilder
in interface ToCopyableBuilder<Decision.Builder,Decision>
public static Decision.Builder builder()
public static Class<? extends Decision.Builder> serializableBuilderClass()
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