/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
private async Task <WorkflowActivityOutput> CompleteInternalAsync <TInput>(
IWorkflowActivityBase activity, CancellationToken cancellationToken, TInput input)
where TInput : WorkflowActivityInput
{
if (CurrentActivityIds.Contains(activity.Id))
{
input = CreateActivityInput(activity, input);
WorkflowActivityOutput result;
try
{
result = await activity.CompleteAsync(input, cancellationToken);
}
catch (Exception exception)
{
return(HandleCompletionException(exception));
}
if (result.Successful)
{
return(await HandleCompletionSuccess(activity, result));
}
else
{
return(HandleCompletionFailed(result));
}
}
throw new WorkflowException("The activity to complete could not be found in the current activity list. ");
}
/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
private TInput CreateActivityInput <TInput>(IWorkflowActivityBase activity, TInput input)
where TInput : WorkflowActivityInput
{
input = input ?? (TInput)Activator.CreateInstance(activity.InputType);
input.Instance = this;
foreach (var route in activity.Routes)
{
var outputData = Data.FirstOrDefault(d => d.ActivityId == route.OutputActivityId);
if (outputData != null)
{
var inputProperty = input.GetType().GetRuntimeProperty(route.InputProperty);
if (inputProperty != null)
{
var outputProperty = outputData.Output.GetType().GetRuntimeProperty(route.OutputProperty);
if (outputProperty != null)
{
inputProperty.SetValue(input, outputProperty.GetValue(outputData.Output));
}
else
{
throw new WorkflowException("The output property of the route could not be found on the output data. ");
}
}
else
{
throw new WorkflowException("The input property of the route could not be found on the input data. ");
}
}
else
{
throw new WorkflowException("The requested input data for the activity could not be found. ");
}
}
return(input);
}
/// <summary>Gets the next activities or null when no condition is available. </summary>
/// <param name="activity">The current workflow activity. </param>
/// <param name="definition">The workflow definition. </param>
/// <returns>The next activities. </returns>
/// <exception cref="WorkflowException">No next activities could be found based on the given condition. </exception>
/// <exception cref="WorkflowException">More then one activity found for condition but activity is not a ForkActivity. </exception>
public IWorkflowActivityBase[] GetNextActivities(IWorkflowActivityBase activity, WorkflowDefinition definition)
{
if (string.IsNullOrEmpty(NextActivitiesCondition))
{
return(null);
}
var nextActivities = definition.GetOutboundTransitions(activity)
.Where(t => t.Condition == NextActivitiesCondition)
.Select(t => definition.GetActivityById(t.To))
.ToArray();
if (nextActivities.Length == 0)
{
throw new WorkflowException(
string.Format("No next activities could be found based on the given condition '{0}'. ", NextActivitiesCondition));
}
if (nextActivities.Length > 1 && !(activity is ForkActivity))
{
throw new WorkflowException(
string.Format("More then one activity found for condition '{0}' " +
"but activity is not a ForkActivity. ", NextActivitiesCondition));
}
return(nextActivities);
}
/// <summary>Initializes a new instance of the <see cref="WorkflowRoute"/> class. </summary>
/// <typeparam name="TOutputActivity">The type of the output activity's output. </typeparam>
/// <typeparam name="TInputActivity">The type of the input activity's input. </typeparam>
/// <param name="outputActivity">The output activity. </param>
/// <param name="outputPropertyExpression">The output property as expression. </param>
/// <param name="inputPropertyExpression">The output property as expression. </param>
/// <returns>The <see cref="WorkflowRoute"/>. </returns>
public static WorkflowRoute Create <TOutputActivity, TInputActivity>(IWorkflowActivityBase outputActivity,
Expression <Func <TOutputActivity, object> > outputPropertyExpression,
Expression <Func <TInputActivity, object> > inputPropertyExpression)
where TInputActivity : WorkflowActivityInput
where TOutputActivity : WorkflowActivityOutput
{
return(Create(outputActivity.Id, outputPropertyExpression, inputPropertyExpression));
}
/// <exception cref="WorkflowException">Default outgoing transitions of cannot be conditional. </exception>
private IWorkflowActivityBase[] GetDefaultNextActivities(IWorkflowActivityBase activity)
{
var transitions = WorkflowDefinition.GetOutboundTransitions(activity).ToArray();
if (transitions.Any(t => t.IsConditional))
{
throw new WorkflowException(string.Format("Default outgoing transitions of ({0}) cannot be conditional. ", activity.Id));
}
return(transitions
.Select(t => WorkflowDefinition.GetActivityById(t.To))
.ToArray());
}
private void AddActivityResultToData(IWorkflowActivityBase activity, WorkflowActivityOutput result)
{
var data = Data.SingleOrDefault(d => d.ActivityId == activity.Id);
if (data != null)
{
Data.Remove(data);
}
Data.Add(new ActivityData {
ActivityId = activity.Id, Output = result
});
}
/// <summary>Executes the given activity with the given arguments. </summary>
/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
public async Task <WorkflowActivityOutput> CompleteAsync <TInput>(
IWorkflowActivityBase activity, CancellationToken cancellationToken, TInput input)
where TInput : WorkflowActivityInput
{
try
{
IsRunning = true;
return(await CompleteInternalAsync(activity, cancellationToken, input));
}
finally
{
IsRunning = false;
RaiseCurrentActivitiesChanged();
}
}
private bool HasCurrentActivityBeforeActivity(WorkflowActivityInput input, WorkflowDefinition definition,
IWorkflowActivityBase activity, List<WorkflowTransition> checkedTransitions)
{
var inboundTransitions = definition.GetInboundTransitions(activity);
if (inboundTransitions.Any(t => input.Instance.CurrentActivityIds.Contains(t.From)))
return true;
checkedTransitions.AddRange(inboundTransitions);
foreach (var transition in inboundTransitions)
{
if (HasCurrentActivityBeforeActivity(input, definition, definition.GetActivityById(transition.From), checkedTransitions))
return true;
}
return false;
}
/// <summary>Gets the next activities or null when no condition is available. </summary>
/// <param name="activity">The current workflow activity. </param>
/// <param name="definition">The workflow definition. </param>
/// <returns>The next activities. </returns>
/// <exception cref="WorkflowException">No next activities could be found based on the given condition. </exception>
/// <exception cref="WorkflowException">More then one activity found for condition but activity is not a ForkActivity. </exception>
public IWorkflowActivityBase[] GetNextActivities(IWorkflowActivityBase activity, WorkflowDefinition definition)
{
if (string.IsNullOrEmpty(NextActivitiesCondition))
return null;
var nextActivities = definition.GetOutboundTransitions(activity)
.Where(t => t.Condition == NextActivitiesCondition)
.Select(t => definition.GetActivityById(t.To))
.ToArray();
if (nextActivities.Length == 0)
throw new WorkflowException(
string.Format("No next activities could be found based on the given condition '{0}'. ", NextActivitiesCondition));
if (nextActivities.Length > 1 && !(activity is ForkActivity))
throw new WorkflowException(
string.Format("More then one activity found for condition '{0}' " +
"but activity is not a ForkActivity. ", NextActivitiesCondition));
return nextActivities;
}
private bool HasCurrentActivityBeforeActivity(WorkflowActivityInput input, WorkflowDefinition definition,
IWorkflowActivityBase activity, List <WorkflowTransition> checkedTransitions)
{
var inboundTransitions = definition.GetInboundTransitions(activity);
if (inboundTransitions.Any(t => input.Instance.CurrentActivityIds.Contains(t.From)))
{
return(true);
}
checkedTransitions.AddRange(inboundTransitions);
foreach (var transition in inboundTransitions)
{
if (HasCurrentActivityBeforeActivity(input, definition, definition.GetActivityById(transition.From), checkedTransitions))
{
return(true);
}
}
return(false);
}
/// <exception cref="WorkflowException">A workflow validation exception occurred. </exception>
private void ValidateRoute(IWorkflowActivityBase inputActivity, WorkflowRoute route)
{
var outputActivity = GetActivityById(route.OutputActivityId);
var outputProperty = outputActivity.OutputType.GetRuntimeProperty(route.OutputProperty);
if (outputProperty == null)
{
throw new WorkflowException("The output property of the route could not be found on the output data type. ");
}
var inputProperty = inputActivity.InputType.GetRuntimeProperty(route.InputProperty);
if (inputProperty == null)
{
throw new WorkflowException("The input property of the route could not be found on the input data type. ");
}
if (outputProperty.PropertyType != inputProperty.PropertyType)
{
throw new WorkflowException("The input property and output property types of a route do not match. ");
}
}
/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
private async Task <WorkflowActivityOutput> HandleCompletionSuccess(IWorkflowActivityBase activity, WorkflowActivityOutput result)
{
AddActivityResultToData(activity, result);
var nextActivities = result.GetNextActivities(activity, WorkflowDefinition);
if (nextActivities == null)
{
nextActivities = GetDefaultNextActivities(activity);
}
if (!(activity is ForkActivity) && nextActivities.Length > 1)
{
throw new WorkflowException(string.Format("Activity ({0}) has multiple next activities ({1}) " +
"but only ForkActivity activities can return multiple activities. ",
activity.Id, string.Join(", ", nextActivities.Select(a => a.Id))));
}
CurrentActivityIds.Remove(activity.Id);
await AddNextActivitiesAsync(activity, nextActivities);
return(result);
}
/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
private async Task AddNextActivitiesAsync(IWorkflowActivityBase activity, IList <IWorkflowActivityBase> nextActivities)
{
var allowedTransitions = WorkflowDefinition.GetOutboundTransitions(activity);
var hasFollowingActivities = allowedTransitions.Length > 0;
if (!hasFollowingActivities)
{
return;
}
var areNextActivitiesAllowed = nextActivities.All(a => allowedTransitions.Any(t => t.To == a.Id));
if (areNextActivitiesAllowed)
{
await PrepareNextActivities(nextActivities);
}
else
{
throw new WorkflowException(
string.Format("Transitions for activities ({0}) produced by activity ({1}) could not be found. ",
string.Join(", ", nextActivities.Select(a => a.Id)), activity.Id));
}
}
/// <summary>Gets the inbound transitions of a given inputActivity. </summary>
/// <param name="activity">The inputActivity. </param>
/// <returns>The transitions. </returns>
public WorkflowTransition[] GetInboundTransitions(IWorkflowActivityBase activity)
{
return(Transitions.Where(t => t.To == activity.Id).ToArray());
}
/// <summary>Initializes a new instance of the <see cref="WorkflowRoute"/> class. </summary>
/// <param name="outputActivity">The output activity. </param>
/// <param name="outputProperty">The output property defined on the output activity's output type. </param>
/// <param name="inputProperty">The input property defined on the input activity's input type. </param>
public WorkflowRoute(IWorkflowActivityBase outputActivity, string outputProperty, string inputProperty)
{
OutputActivityId = outputActivity.Id;
OutputProperty = outputProperty;
InputProperty = inputProperty;
}
/// <exception cref="WorkflowException">A workflow validation exception occurred. </exception>
private void ValidateRoute(IWorkflowActivityBase inputActivity, WorkflowRoute route)
{
var outputActivity = GetActivityById(route.OutputActivityId);
var outputProperty = outputActivity.OutputType.GetRuntimeProperty(route.OutputProperty);
if (outputProperty == null)
throw new WorkflowException("The output property of the route could not be found on the output data type. ");
var inputProperty = inputActivity.InputType.GetRuntimeProperty(route.InputProperty);
if (inputProperty == null)
throw new WorkflowException("The input property of the route could not be found on the input data type. ");
if (outputProperty.PropertyType != inputProperty.PropertyType)
throw new WorkflowException("The input property and output property types of a route do not match. ");
}
/// <summary>Gets the inbound transitions of a given inputActivity. </summary>
/// <param name="activity">The inputActivity. </param>
/// <returns>The transitions. </returns>
public WorkflowTransition[] GetInboundTransitions(IWorkflowActivityBase activity)
{
return Transitions.Where(t => t.To == activity.Id).ToArray();
}
/// <summary>Initializes a new instance of the <see cref="WorkflowTransition"/> class. </summary>
public WorkflowTransition(IWorkflowActivityBase from, IWorkflowActivityBase to)
{
From = from.Id;
To = to.Id;
}
/// <summary>Initializes a new instance of the <see cref="WorkflowTransition"/> class. </summary>
public WorkflowTransition(IWorkflowActivityBase from, IWorkflowActivityBase to)
{
From = from.Id;
To = to.Id;
}
/// <summary>Executes the given activity with the given arguments. </summary>
/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
public Task <WorkflowActivityOutput> CompleteAsync(IWorkflowActivityBase activity, CancellationToken cancellationToken)
{
return(CompleteAsync <WorkflowActivityInput>(activity, cancellationToken, null));
}
/// <summary>Executes the given activity with the given arguments. </summary>
/// <exception cref="WorkflowException">A workflow exception occurred. </exception>
public Task <WorkflowActivityOutput> CompleteAsync <TInput>(IWorkflowActivityBase activity, TInput input)
where TInput : WorkflowActivityInput
{
return(CompleteAsync(activity, CancellationToken.None, input));
}