public async Task <WorkflowExecutionContext> InvokeAsync(Workflow workflow, IActivity startActivity = default, Variables arguments = default, CancellationToken cancellationToken = default)
{
workflow.Arguments = arguments ?? new Variables();
var workflowExecutionContext = new WorkflowExecutionContext(workflow);
var isResuming = workflowExecutionContext.Workflow.Status == WorkflowStatus.Resuming;
// If a start activity was provided, remove it from the blocking activities list. If not start activity was provided, pick the first one that has no inbound connections.
if (startActivity != null)
{
workflow.BlockingActivities.Remove(startActivity);
}
else
{
startActivity = workflow.GetStartActivities().FirstOrDefault();
}
if (!isResuming)
{
workflow.StartedAt = clock.GetCurrentInstant();
}
workflowExecutionContext.Workflow.Status = WorkflowStatus.Executing;
if (startActivity != null)
{
workflowExecutionContext.ScheduleActivity(startActivity);
}
// Keep executing activities as long as there are any scheduled.
while (workflowExecutionContext.HasScheduledActivities)
{
var currentActivity = workflowExecutionContext.PopScheduledActivity();
var result = await ExecuteActivityAsync(workflowExecutionContext, currentActivity, isResuming, cancellationToken);
if (result == null)
{
break;
}
await result.ExecuteAsync(this, workflowExecutionContext, cancellationToken);
workflowExecutionContext.IsFirstPass = false;
isResuming = false;
}
// Any other status than Halted means the workflow has ended (either because it reached the final activity, was aborted or has faulted).
if (workflowExecutionContext.Workflow.Status != WorkflowStatus.Halted)
{
workflowExecutionContext.Finish(clock.GetCurrentInstant());
}
else
{
// Persist workflow before executing the halted activities.
await workflowStore.SaveAsync(workflow, cancellationToken);
// Invoke Halted event on activity drivers that halted the workflow.
while (workflowExecutionContext.HasScheduledHaltingActivities)
{
var currentActivity = workflowExecutionContext.PopScheduledHaltingActivity();
var result = await ExecuteActivityHaltedAsync(workflowExecutionContext, currentActivity, cancellationToken);
await result.ExecuteAsync(this, workflowExecutionContext, cancellationToken);
}
}
await workflowStore.SaveAsync(workflow, cancellationToken);
return(workflowExecutionContext);
}