private async Task <ActivityExecutionResult> ExecuteSynchronousActivities(StateExecutionContext stateExecutionContext, CancellationToken cancellationToken = default)
{
// take only synchronous activities in order they are defined in configuration
var synchronousActivities = stateExecutionContext.StateConfiguration.Activities
.Where(a => a.Type == ActivityTypeConfiguration.Synchronous)
.ToList();
if (synchronousActivities.Any())
{
foreach (var activityConfiguration in synchronousActivities)
{
var activityExecutionContext = new ActivityExecutionContext(
stateExecutionContext, activityConfiguration);
var activityExecutionResult = await _activityProcessor.Process(activityExecutionContext, cancellationToken).ConfigureAwait(false);
if (activityExecutionResult.Status == ActivityExecutionStatus.Failed || activityExecutionResult.Status == ActivityExecutionStatus.FailedNoRetry)
{
return(activityExecutionResult);
}
}
}
else
{
Log.Verbose("State [{state}] does not have any synchronous activity to execute [{workflowInstanceId}]",
stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
}
return(new ActivityExecutionResult(ActivityExecutionStatus.Completed));
}
private async Task <StateExecutionTransition> EvaluateNonDelayTransitions(StateExecutionContext stateExecutionContext, CancellationToken cancellationToken)
{
// evaluate transitions in the same order they came from configuration
var nonDelayTransitions = stateExecutionContext.StateConfiguration.Transitions
.Where(t => t.Type != TransitionTypeConfiguration.AsynchronousWithDelay)
.ToList();
if (nonDelayTransitions.Any())
{
foreach (var transitionConfiguration in nonDelayTransitions)
{
var transitionEvaluationResult = await _transitionProcessor.Evaluate(stateExecutionContext, transitionConfiguration, cancellationToken).ConfigureAwait(false);
if (transitionEvaluationResult.Status == TransitionEvaluationStatus.EvaluatedTrue)
{
// first evaluated to true transition wins
return(new StateExecutionTransition(StateTypeConfiguration.Application, transitionConfiguration));
}
}
}
else
{
Log.Verbose("State [{state}] does not have any synchronous activity to execute [{workflowInstanceId}]",
stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
}
return(new StateExecutionTransition(StateTypeConfiguration.Undefined, null));
}
private static IList <StateExecutionTransition> GetDelayedTransitions(StateExecutionContext stateExecutionContext)
{
var delayedTransitions = stateExecutionContext.StateConfiguration.Transitions
.Where(t => t.Type == TransitionTypeConfiguration.AsynchronousWithDelay)
.ToList();
if (delayedTransitions.Count == 0)
{
return(null);
}
var stateExecutionTransitions = new List <StateExecutionTransition>(delayedTransitions.Count);
foreach (var transitionConfiguration in delayedTransitions)
{
stateExecutionTransitions.Add(new StateExecutionTransition(StateTypeConfiguration.Application, transitionConfiguration));
}
return(stateExecutionTransitions);
}
private async Task ScheduleDelayedTransitions(StateExecutionContext stateExecutionContext,
IEnumerable <StateExecutionTransition> delayedTransitions, CancellationToken cancellationToken)
{
foreach (var delayedTransition in delayedTransitions)
{
var delay = TimeSpan.FromSeconds(delayedTransition.TransitionConfiguration.Delay.GetValueOrDefault());
var workflowMessage = new DelayedTransitionWorkflowMessage(
stateExecutionContext.WorkflowContext.WorkflowConfiguration.Id, stateExecutionContext.WorkflowContext.WorkflowInstance.Id, delay,
stateExecutionContext.StateConfiguration.Code, delayedTransition.TransitionConfiguration.MoveToState);
var endpointConfiguration = stateExecutionContext.WorkflowContext.WorkflowConfiguration.RuntimeConfiguration.EndpointConfiguration;
await _workflowEngine.WorkflowEngineBuilder.WorkflowMessageTransportFactoryProvider
.CreateMessageTransportFactory(endpointConfiguration.Type)
.CreateMessageTransport(endpointConfiguration.Address)
.SendWithDelay(endpointConfiguration, workflowMessage, cancellationToken)
.ConfigureAwait(false);
Log.Debug("Scheduled delayed transition for {workflowInstanceId} to {state}",
stateExecutionContext.WorkflowContext.WorkflowInstance.Id, delayedTransition.TransitionConfiguration.MoveToState);
}
}
private static async Task InvokeListenerOnAfterExecutionActivities(StateExecutionContext stateExecutionContext, IStateListener stateListener, CancellationToken cancellationToken = default)
{
if (null == stateListener)
{
return;
}
Log.Verbose("State processing [{state}] listener [after activities] [{workflowInstanceId}]",
stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
try
{
await stateListener.AfterExecutionActivities(stateExecutionContext, cancellationToken).ConfigureAwait(false);
}
catch (Exception ex)
{
throw new WorkflowException(string.Format(CultureInfo.InvariantCulture,
"An error has occurred during execution of an state [{0}] listener [after activities] for workflow instance [{1}]",
stateExecutionContext.StateConfiguration.Code,
stateExecutionContext.WorkflowContext.WorkflowInstance.Id), ex);
}
}
public async Task <StateExecutionResult> Process(StateExecutionContext stateExecutionContext, CancellationToken cancellationToken = default)
{
// 1. log starting
// 2. listener --> before processing
// 3. run activities
// 3.1. execute all synchronous activities
// 3.2. TODO: schedule all asynchronous activities
// 4. listener --> after activities
// 5. if state is final --> report and exit
// 6. evaluate non-delayed transitions
// 6.1. coded transitions
// 6.2. compiled conditions
// 7. schedule all delayed transitions
// 8. log finishing
IStateListener stateListener = null;
StateExecutionResult stateExecutionResult = null;
var workflowInstance = stateExecutionContext.WorkflowContext.WorkflowInstance;
try
{
Log.Verbose("Starting processing state [{type}::{state}] [{workflowInstanceId}]", stateExecutionContext.StateConfiguration.Type,
stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
workflowInstance.CurrentStateCode = stateExecutionContext.StateConfiguration.Code;
workflowInstance.CurrentStateProgress = StateExecutionProgress.Started;
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
stateListener = GetStateListener(stateExecutionContext.WorkflowContext);
workflowInstance.CurrentStateProgress = StateExecutionProgress.BeforeActivities;
await InvokeListenerOnBeforeExecutingState(stateExecutionContext, stateListener, cancellationToken).ConfigureAwait(false);
var activityExecutionResult = await ExecuteSynchronousActivities(stateExecutionContext, cancellationToken).ConfigureAwait(false);
if (activityExecutionResult.Status.IsFailed())
{
workflowInstance.CurrentStateProgress = StateExecutionProgress.Completed;
if (!string.IsNullOrEmpty(activityExecutionResult.TransitionToUse))
{
var transitionConfiguration = stateExecutionContext.StateConfiguration.Transitions.FirstOrDefault(tc =>
string.Equals(tc.MoveToState, activityExecutionResult.TransitionToUse, StringComparison.OrdinalIgnoreCase));
if (null == transitionConfiguration)
{
throw new WorkflowException(string.Format(CultureInfo.InvariantCulture,
"Cannot not find transition [{0}] for failed activity in status [{1}], [workflow ID={2:D}]",
activityExecutionResult.TransitionToUse,
stateExecutionContext.StateConfiguration.Code,
stateExecutionContext.WorkflowContext.WorkflowInstance.Id));
}
Log.Verbose("[{type}::{state}] has been failed, transitioning to custom {failureState} [{workflowInstanceId}]",
stateExecutionContext.StateConfiguration.Type, stateExecutionContext.StateConfiguration.Code,
transitionConfiguration.MoveToState, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
// stateExecutionResult is being used later in the final block
stateExecutionResult = new StateExecutionResult(StateExecutionStatus.Failed, new StateExecutionTransition(StateTypeConfiguration.Application, transitionConfiguration));
return(stateExecutionResult);
}
Log.Verbose("[{type}::{state}] has been failed [{workflowInstanceId}]", stateExecutionContext.StateConfiguration.Type,
stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
// stateExecutionResult is being used later in the final block
stateExecutionResult = new StateExecutionResult(StateExecutionStatus.Failed, new StateExecutionTransition(StateTypeConfiguration.Failed, null));
return(stateExecutionResult);
}
workflowInstance.CurrentStateProgress = StateExecutionProgress.AfterActivitiesProcessed;
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
await InvokeListenerOnAfterExecutionActivities(stateExecutionContext, stateListener, cancellationToken).ConfigureAwait(false);
if (stateExecutionContext.StateConfiguration.Type == StateTypeConfiguration.Failed ||
stateExecutionContext.StateConfiguration.Type == StateTypeConfiguration.Final)
{
Log.Verbose("[{type}::{state}] has been completed [{workflowInstanceId}]", stateExecutionContext.StateConfiguration.Type,
stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
workflowInstance.CurrentStateProgress = StateExecutionProgress.Completed;
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
// stateExecutionResult is being used later in the final block
stateExecutionResult = new StateExecutionResult(StateExecutionStatus.Finished, new StateExecutionTransition(StateTypeConfiguration.Undefined, null));
return(stateExecutionResult);
}
workflowInstance.CurrentStateProgress = StateExecutionProgress.BeforeTransitions;
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
var stateExecutionTransition = await EvaluateNonDelayTransitions(stateExecutionContext, cancellationToken).ConfigureAwait(false);
var delayedStateExecutionTransitions = GetDelayedTransitions(stateExecutionContext);
if (stateExecutionTransition.NextStateType == StateTypeConfiguration.Undefined && null == delayedStateExecutionTransitions)
{
throw new WorkflowException(string.Format(CultureInfo.InvariantCulture,
"Cannot evaluate transition(s) for non final state [{0}], [workflow ID={1:D}]",
stateExecutionContext.StateConfiguration.Code,
stateExecutionContext.WorkflowContext.WorkflowInstance.Id));
}
if (null != delayedStateExecutionTransitions)
{
await ScheduleDelayedTransitions(stateExecutionContext, delayedStateExecutionTransitions, cancellationToken)
.ConfigureAwait(false);
}
workflowInstance.CurrentStateProgress = StateExecutionProgress.Completed;
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
stateExecutionResult = new StateExecutionResult(StateExecutionStatus.Completed, stateExecutionTransition);
return(stateExecutionResult);
}
catch (Exception ex)
{
Log.Error(ex, "An error has occurred during processing state [{type}::{state}] [{workflowInstanceId}]",
stateExecutionContext.StateConfiguration.Type, stateExecutionContext.StateConfiguration.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
workflowInstance.CurrentStateProgress = StateExecutionProgress.Completed;
if (stateExecutionContext.StateConfiguration.Type == StateTypeConfiguration.Failed)
{
stateExecutionResult = new StateExecutionResult(StateExecutionStatus.Failed, new StateExecutionTransition(StateTypeConfiguration.Undefined, null));
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
return(stateExecutionResult);
}
stateExecutionResult = new StateExecutionResult(StateExecutionStatus.Failed, new StateExecutionTransition(StateTypeConfiguration.Failed, null));
await _workflowEngine.SaveWorkflowInstance(workflowInstance, cancellationToken).ConfigureAwait(false);
return(stateExecutionResult);
}
finally
{
await InvokeListenerOnAfterExecutionState(stateExecutionContext, stateListener, stateExecutionResult, cancellationToken).ConfigureAwait(false);
Log.Debug("Finished processing state [{type}::{code}], {status}, {nextState} [{workflowInstanceId}]",
stateExecutionContext.StateConfiguration.Type, stateExecutionContext.StateConfiguration.Code,
stateExecutionResult?.Status, stateExecutionResult?.Transition.TransitionConfiguration?.Code, stateExecutionContext.WorkflowContext.WorkflowInstance.Id);
}
}