async Task <OrchestrationExecutionCursor> ExecuteOrchestrationAsync(OrchestrationRuntimeState runtimeState, TaskOrchestrationWorkItem workItem)
{
// Get the TaskOrchestration implementation. If it's not found, it either means that the developer never
// registered it (which is an error, and we'll throw for this further down) or it could be that some custom
// middleware (e.g. out-of-process execution middleware) is intended to implement the orchestration logic.
TaskOrchestration?taskOrchestration = this.objectManager.GetObject(runtimeState.Name, runtimeState.Version !);
var dispatchContext = new DispatchMiddlewareContext();
dispatchContext.SetProperty(runtimeState.OrchestrationInstance);
dispatchContext.SetProperty(taskOrchestration);
dispatchContext.SetProperty(runtimeState);
dispatchContext.SetProperty(workItem);
TaskOrchestrationExecutor?executor = null;
await this.dispatchPipeline.RunAsync(dispatchContext, _ =>
{
// Check to see if the custom middleware intercepted and substituted the orchestration execution
// with its own execution behavior, providing us with the end results. If so, we can terminate
// the dispatch pipeline here.
var resultFromMiddleware = dispatchContext.GetProperty <OrchestratorExecutionResult>();
if (resultFromMiddleware != null)
{
return(CompletedTask);
}
if (taskOrchestration == null)
{
throw TraceHelper.TraceExceptionInstance(
TraceEventType.Error,
"TaskOrchestrationDispatcher-TypeMissing",
runtimeState.OrchestrationInstance,
new TypeMissingException($"Orchestration not found: ({runtimeState.Name}, {runtimeState.Version})"));
}
executor = new TaskOrchestrationExecutor(
runtimeState,
taskOrchestration,
this.orchestrationService.EventBehaviourForContinueAsNew,
this.errorPropagationMode);
OrchestratorExecutionResult resultFromOrchestrator = executor.Execute();
dispatchContext.SetProperty(resultFromOrchestrator);
return(CompletedTask);
});
var result = dispatchContext.GetProperty <OrchestratorExecutionResult>();
IEnumerable <OrchestratorAction> decisions = result?.Actions ?? Enumerable.Empty <OrchestratorAction>();
runtimeState.Status = result?.CustomStatus;
return(new OrchestrationExecutionCursor(runtimeState, taskOrchestration, executor, decisions));
}
async Task ResumeOrchestrationAsync(TaskOrchestrationWorkItem workItem)
{
OrchestrationExecutionCursor cursor = workItem.Cursor;
var dispatchContext = new DispatchMiddlewareContext();
dispatchContext.SetProperty(cursor.RuntimeState.OrchestrationInstance);
dispatchContext.SetProperty(cursor.TaskOrchestration);
dispatchContext.SetProperty(cursor.RuntimeState);
dispatchContext.SetProperty(workItem);
cursor.LatestDecisions = Enumerable.Empty <OrchestratorAction>();
await this.dispatchPipeline.RunAsync(dispatchContext, _ =>
{
OrchestratorExecutionResult result = cursor.OrchestrationExecutor.ExecuteNewEvents();
dispatchContext.SetProperty(result);
return(CompletedTask);
});
var result = dispatchContext.GetProperty <OrchestratorExecutionResult>();
cursor.LatestDecisions = result?.Actions ?? Enumerable.Empty <OrchestratorAction>();
cursor.RuntimeState.Status = result?.CustomStatus;
}