void SetMarkerEvents()

in src/DurableTask.Core/OrchestrationRuntimeState.cs [266:319]
46 lines of code
10 McCabe index (conditional complexity)

        void SetMarkerEvents(HistoryEvent historyEvent)
        {
            if (historyEvent is ExecutionStartedEvent startedEvent)
            {
                if (ExecutionStartedEvent != null)
                {
                    throw new InvalidOperationException(
                        "Multiple ExecutionStartedEvent found, potential corruption in state storage");
                }

                ExecutionStartedEvent = startedEvent;
            }
            else if (historyEvent is ExecutionCompletedEvent completedEvent)
            {
                if (ExecutionCompletedEvent == null)
                {
                    ExecutionCompletedEvent = completedEvent;
                    orchestrationStatus = completedEvent.OrchestrationStatus;
                }
                else
                {
                    // It's not generally expected to receive multiple execution completed events for a given orchestrator, but it's possible under certain race conditions.
                    // For example: when an orchestrator is signaled to terminate at the same time as it attempts to continue-as-new.
                    var log = $"Received new {completedEvent.GetType().Name} event despite the orchestration being already in the {orchestrationStatus} state.";
                    
                    if (orchestrationStatus == OrchestrationStatus.ContinuedAsNew && completedEvent.OrchestrationStatus == OrchestrationStatus.Terminated)
                    {
                        // If the orchestration planned to continue-as-new but termination is requested, we transition to the terminated state.
                        // This is because termination should be considered to be forceful.
                        log += " Discarding previous 'ExecutionCompletedEvent' as termination is forceful.";
                        ExecutionCompletedEvent = completedEvent;
                        orchestrationStatus = completedEvent.OrchestrationStatus;
                    }
                    else
                    {
                        // otherwise, we ignore the new event.
                        log += " Discarding new 'ExecutionCompletedEvent'.";
                    }

                    LogHelper?.OrchestrationDebugTrace(this.OrchestrationInstance?.InstanceId ?? "", this.OrchestrationInstance?.ExecutionId ?? "", log);
                }
            }
            else if (historyEvent is ExecutionSuspendedEvent)
            {
                orchestrationStatus = OrchestrationStatus.Suspended;
            }
            else if (historyEvent is ExecutionResumedEvent)
            {
                if (ExecutionCompletedEvent == null)
                {
                    orchestrationStatus = OrchestrationStatus.Running;
                }
            }
        }