/// <summary>
/// Process activity task
/// </summary>
/// <param name="input">Input for the activity task</param>
/// <returns>Processing result: either an updated SWF activity, or an error message</returns>
private async Task <ProcessSwfActivityResult> ProcessTask(string input)
{
ProcessSwfActivityResult result = new ProcessSwfActivityResult();
try
{
//read SWF activity info
SwfActivity swfActivity = JsonSerializer.Deserialize <SwfActivity>(input);
//based on SWF activity's info create an EMR activity
SingleEmrActivityIterator singleEmrActivityIterator = new SingleEmrActivityIterator(swfActivity);
//Run this activity on EMR Service
using (EmrActivitiesRunner emrRunner = new EmrActivitiesRunner(this.EmrJobLogger, this.EmrJobStateChecker, this.EmrClient, this.Settings, singleEmrActivityIterator))
{
emrRunner.JobFlowId = swfActivity.JobFlowId; //set JobFlowId for the current activity
bool emrJobOk = await emrRunner.Start();
if (emrJobOk)
{
swfActivity.JobFlowId = emrRunner.JobFlowId; //read JobFlowId in case it was changed (for example, during starting a new EMR job)
result.Output = swfActivity;
}
else
{
result.ErrorMessage = emrRunner.ErrorMessage;
}
}
}
catch (Exception ex)
{
result.ErrorMessage = ex.Message;
}
return(result);
}
private List <Decision> Decide(DecisionTask task)
{
List <Decision> decisions = new List <Decision>();
SwfActivity latestActivity = null;
HistoryEvent latestEvent = task.Events[0];
if (latestEvent.EventType == EventType.ActivityTaskCompleted)
{
latestActivity = JsonSerializer.Deserialize <SwfActivity>(latestEvent.ActivityTaskCompletedEventAttributes.Result);
}
SwfActivity nextActivity = this.CreateNextEmrActivity(latestActivity);
if (nextActivity == null)
{
decisions.Add(this.CreateCompleteWorkflowExecutionDecision());
}
else
{
decisions.Add(this.CreateActivityDecision(nextActivity));
}
return(decisions);
}
private SwfActivity CreateNextEmrActivity(SwfActivity previousActivity)
{
if (previousActivity == null)
{
return(new SwfActivity()
{
Name = "startCluster",
Type = EmrActivityType.StartJob
});
}
switch (previousActivity.Name)
{
case "startCluster":
return(new SwfActivity()
{
Name = "runSteps",
JobFlowId = previousActivity.JobFlowId,
Type = EmrActivityType.AddSteps
});
case "runSteps":
return(new SwfActivity()
{
Name = "terminateCluster",
JobFlowId = previousActivity.JobFlowId,
Type = EmrActivityType.TerminateJob
});
}
return(null);
}
private async Task CompleteTask(String taskToken, SwfActivity swfActivity)
{
RespondActivityTaskCompletedRequest request = new RespondActivityTaskCompletedRequest()
{
Result = JsonSerializer.Serialize <SwfActivity>(swfActivity),
TaskToken = taskToken
};
RespondActivityTaskCompletedResponse response = await this.SwfClient.RespondActivityTaskCompletedAsync(request);
this.EmrJobLogger.PrintInfo(string.Format(SwfResources.Info_ActivityCompletedTemplate, swfActivity.Name, swfActivity.JobFlowId));
}
private Decision CreateActivityDecision(SwfActivity nextActivity)
{
Decision decision = new Decision()
{
DecisionType = DecisionType.ScheduleActivityTask,
ScheduleActivityTaskDecisionAttributes = new ScheduleActivityTaskDecisionAttributes()
{
ActivityType = new ActivityType()
{
Name = this.SwfConfiguration.ActivityName,
Version = this.SwfConfiguration.ActivityVersion
},
ActivityId = this.SwfConfiguration.ActivityIdPrefix + DateTime.Now.TimeOfDay,
Input = JsonSerializer.Serialize <SwfActivity>(nextActivity)
}
};
this.EmrJobLogger.PrintAddingNewActivity(nextActivity.Name);
return(decision);
}
private static EmrActivity CreateStrategy(SwfActivity swfActivity)
{
XmlDocument xml = new XmlDocument();
xml.Load(swfActivity.Path);
switch (swfActivity.Type)
{
case EmrActivityType.StartJob:
return(new StartJobActivity(swfActivity.Name, xml));
case EmrActivityType.AddSteps:
return(new AddStepsActivity(swfActivity.Name, xml));
case EmrActivityType.TerminateJob:
return(new TerminateJobActivity(swfActivity.Name));
default:
throw new InvalidOperationException(string.Format(SwfResources.E_UnsupportedEmrActivityTypeTemplate, swfActivity.Type));
}
}
public SingleEmrActivityIterator(SwfActivity swfActivity)
{
this.emrActivity = SingleEmrActivityIterator.CreateStrategy(swfActivity);
}
