public void OnNotifyIdle()
{
bool isTrySetCompleted = activeTaskCompletionSources.TrySetCompleted();
if (completionState != null)
{
if (instance.WorkflowInstanceState == WorkflowInstanceState.Complete)
{
// Completed as expected.
instance = null;
}
else
{
// Typically aborted after completion due to a persistence failure.
completionState = null;
}
}
if (!isTrySetCompleted)
{
idle.Set();
}
}
public Task OnCompletedAsync(ActivityInstanceState completionState, IDictionary <string, object> outputArguments, Exception terminationException)
{
this.completionState = new WorkflowCompletionState(completionState, outputArguments, terminationException);
return(RaiseCompletedAsync(completionState, outputArguments, terminationException));
}
// TODO handle timeout? TimeoutException on this task, and finish preparation in the background and set idle at the end, problem: it shouldn't know about idle!
// Can be called only after a successful WaitIdleAsync()!
private async Task PrepareAsync()
{
if (completionState == null)
{
if (instance != null && instance.WorkflowInstanceState == WorkflowInstanceState.Aborted)
{
// We try to restart or reload it from the previous persisted state.
await grain.LoadWorkflowStateAsync();
instance = null;
}
if (instance == null)
{
IWorkflowState workflowState = grain.WorkflowState;
WorkflowIdentity workflowDefinitionIdentity = null;
IWorkflowInstance instance = null;
WorkflowCompletionState completionState = null;
if (workflowState.InstanceValues == null)
{
// Start, there is no previous persisted state.
workflowDefinitionIdentity = workflowDefinitionIdentityFactory();
instance = new WorkflowInstance(this, workflowDefinitionFactory(workflowDefinitionIdentity), workflowDefinitionIdentity);
instance.Start(await RaiseStartingAsync(), Extensions);
}
else if (!WorkflowInstance.IsCompleted(workflowState.InstanceValues))
{
// Load previous persisted state.
instance = new WorkflowInstance(this, workflowDefinitionFactory(workflowState.WorkflowDefinitionIdentity), workflowState.WorkflowDefinitionIdentity);
// TODO If workflowState.WorkflowDefinitionIdentity differs from workflowDefinitionIdentity, we should create a DynamicUpdateMap and update the loaded instance.
// Currently we downgrade the workflowDefinitionIdentity to the loaded value.
// NOTE The workflowDefinitionFactory usually yields the same singleton workflow definition (ie. activity) for the same WorkflowDefinitionIdentity,
// what happens with these activity trees during update???
// await instance.LoadAsync(workflowState.InstanceValues, GetExtensions(), >>>DynamicUpdateMap: workflowState.WorkflowDefinitionIdentity -> workflowDefinitionIdentity<<<);
await instance.LoadAsync(workflowState.InstanceValues, Extensions);
workflowDefinitionIdentity = workflowState.WorkflowDefinitionIdentity;
}
else
{
completionState = new WorkflowCompletionState();
await completionState.LoadAsync(workflowState.InstanceValues, HostExtensions, Parameters);
}
// Set the the values only, when the instance/completionState was successfully initialized.
this.workflowDefinitionIdentity = workflowDefinitionIdentity;
this.instance = instance;
this.completionState = completionState;
}
if (instance != null && instance.WorkflowInstanceState == WorkflowInstanceState.Runnable)
{
TaskCompletionSource <object> taskCompletionSource = new TaskCompletionSource <object>();
try
{
activeTaskCompletionSources.ProtectionLevel = ActiveTaskCompletionSources.TaskCompletionSourceProtectionLevel.Preparation;
activeTaskCompletionSources.Add(taskCompletionSource);
await instance.RunAsync();
await taskCompletionSource.Task;
}
finally
{
activeTaskCompletionSources.ProtectionLevel = ActiveTaskCompletionSources.TaskCompletionSourceProtectionLevel.Normal;
activeTaskCompletionSources.Remove(taskCompletionSource);
}
}
}
}
