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Iterare sobre la lista de actividades en base a la entrada proporcionada usando AWS SWF

Question

Tengo dos servidores (instancias EC2). En un servidor (servidor 1) tengo 5 lotes y en otro (servidor 2) tengo 6 lotes. Envolví cada lote en actividades y la clase de implementación del flujo de trabajo se proporciona a continuación. Quiero repetir las actividades (actividades completas, incluido el servidor 1 y 2) en función de la fecha de ejecución. Por ejemplo, si la fecha es menor que la fecha actual, ejecute todas las actividades del servidor 1 y 2 a partir de la fecha indicada hasta la fecha actual. Si la fecha de ejecución es igual a la fecha actual, ejecute todas las actividades del servidor 1 y 2 para la fecha actual. Además, si alguna de las actividades de un día arroja alguna excepción, entonces no ejecute las actividades para el día siguiente (<= fecha actual).

 public class JobWorkflowImpl implements JobWorkflow{
private DecisionContextProvider contextProvider
= new DecisionContextProviderImpl();
private WorkflowClock clock
= contextProvider.getDecisionContext().getWorkflowClock();
private BS1JobActivitiesClient bs1ActivitiesClient
= new BS1JobActivitiesClientImpl();
private BS2JobActivitiesClient bs2ActivitiesClient
= new BS2JobActivitiesClientImpl();
@Override
public void executeJob(Date exedate) {
Date today = new Date(clock.currentTimeMillis());
Date toProcess = exedate;
// All date manipulations are pseudocode here as I''m lazy
// to look up the real ones.
Promise<Void> previousDateDone = null;
while(toProcess <= today) {
// Create chain of executeJobForExactDate
// linked by previousDateDone to ensure that they are executed sequentially.
// null Promise is treated as ready promise by the framework.
previousDateDone = executeJobForExactDate(toProcess, previousDateDone);
toProcess.addDay(1);
}
}
Promise<Void> void executeJobForExactDate(Date date, Promise<Void> previous) {
Settable<Integer> firstServerDone = new Settable<Integer>();
Settable<Integer> secondServerDone = new Settable<Integer>();
Settable<Integer> resultODLSLBs1 = new Settable<Integer>();
//TODO Iterate over the activities
new TryCatchFinally(previous){
@Override
protected void doTry(){
Promise<Integer> resultFARBs1 = bs1ActivitiesClient.executecommand1(date);
Promise<Integer> resultUAMLFBs1 = bs1ActivitiesClient.executecommand2(date, resultFARBs1);
Promise<Integer> resultLLPBs1 = bs1ActivitiesClient.executecommand3(date, resultUAMLFBs1);
Promise<Integer> resultODLDLBs1 = bs1ActivitiesClient.executecommand4(date, resultLLPBs1);
// Chain links result of the activity execution
// to an aready existing Settable.
resultODLSLBs1.chain(bs1ActivitiesClient.executecommand5(date, resultODLDLBs1));
}
@Override
protected void doCatch(Throwable e){
throw new MyException("Failed");
}
@Override
protected void doFinally() throws Throwable {
firstServerDone.set(null);
}
};
new TryCatchFinally(previous){
@Override
protected void doTry() {
Promise<Integer> resultFARBs2 = bs2ActivitiesClient.executecommand1(date);
Promise<Integer> resultUAMLFBs2 = bs2ActivitiesClient.executecommand2(date, resultFARBs2);
Promise<Integer> resultLLPBs2 = bs2ActivitiesClient.executecommand3(date, resultUAMLFBs2);
Promise<Integer> resultODLDLBs2 = bs2ActivitiesClient.executecommand4(date, resultLLPBs2);
Promise<Integer> resultODLSLBs2 = bs2ActivitiesClient.executecommand5(date, resultODLDLBs2, resultODLSLBs1);
bs2ActivitiesClient.executecommand6(date, resultODLSLBs2);
}
@Override
protected void doCatch(Throwable e){
throw new MyException("Failed");
}
@Override
protected void doFinally(){
secondServerDone.set(null);
}
};
// AndPromise is done when all of its constructor parameters are done.
// I decided to consider the date processing done when both
// TryCatchFinallies are done. You can implement more complex logic depending on
// the business requirements. One option is to wrap both TryCatcFinallies
// in another TryCatchFinally.
return new AndPromise(firstServerDone, secondServerDone);
}
}

El problema es que, si alguna actividad del servidor 1 arroja alguna excepción, se cancela toda la actividad que no ha comenzado tanto para el servidor 1 como para el servidor 2. Pero solo quiero que la actividad que no se haya ejecutado dentro de un servidor cancelado ya que su propia actividad del servidor ha fallado, el otro servidor debe continuar lo más lejos posible (es decir, el lugar de donde depende).

Answer 1

La parte engañosa es que Flow Framework requiere que use el reloj que proporciona a través del contexto de decisión. De lo contrario, no va a funcionar correctamente. El resto es solo una programación Java asíncrona.

public class JobWorkflowImpl implements JobWorkflow{
private DecisionContextProvider contextProvider
= new DecisionContextProviderImpl();
private WorkflowClock clock
= contextProvider.getDecisionContext().getWorkflowClock();
private BS1JobActivitiesClient bs1ActivitiesClient
= new BS1JobActivitiesClientImpl();
private BS2JobActivitiesClient bs2ActivitiesClient
= new BS2JobActivitiesClientImpl();
@Override
public void executeJob(Date exedate) {
Date today = new Date(clock.currentTimeMillis());
Date toProcess = exedate;
// All date manipulations are pseudocode here as I''m lazy
// to look up the real ones.
Promise<Void> previousDateDone = null;
while(toProcess <= today) {
// Create chain of executeJobForExactDate
// linked by previousDateDone to ensure that they are executed sequentially.
// null Promise is treated as ready promise by the framework.
previousDateDone = executeJobForExactDate(toProcess, previousDateDone);
toProcess.addDay(1);
}
}
Promise<Void> void executeJobForExactDate(Date date, Promise<Void> previous) {
Settable<Integer> firstServerDone = new Settable<Integer>();
Settable<Integer> secondServerDone = new Settable<Integer>();
Settable<Integer> resultODLSLBs1 = new Settable<Integer>();
//TODO Iterate over the activities
new TryCatchFinally(previous){
@Override
protected void doTry(){
Promise<Integer> resultFARBs1 = bs1ActivitiesClient.executecommand1(date);
Promise<Integer> resultUAMLFBs1 = bs1ActivitiesClient.executecommand2(date, resultFARBs1);
Promise<Integer> resultLLPBs1 = bs1ActivitiesClient.executecommand3(date, resultUAMLFBs1);
Promise<Integer> resultODLDLBs1 = bs1ActivitiesClient.executecommand4(date, resultLLPBs1);
// Chain links result of the activity execution
// to an aready existing Settable.
resultODLSLBs1.chain(bs1ActivitiesClient.executecommand5(date, resultODLDLBs1));
}
@Override
protected void doCatch(Throwable e){
System.out.println("Failed to execute BS1 daily job");
}
@Override
protected void doFinally() throws Throwable {
firstServerDone.set(null);
}
};
new TryCatchFinally(previous){
@Override
protected void doTry() {
Promise<Integer> resultFARBs2 = bs2ActivitiesClient.executecommand1(date);
Promise<Integer> resultUAMLFBs2 = bs2ActivitiesClient.executecommand2(date, resultFARBs2);
Promise<Integer> resultLLPBs2 = bs2ActivitiesClient.executecommand3(date, resultUAMLFBs2);
Promise<Integer> resultODLDLBs2 = bs2ActivitiesClient.executecommand4(date, resultLLPBs2);
Promise<Integer> resultODLSLBs2 = bs2ActivitiesClient.executecommand5(date, resultODLDLBs2, resultODLSLBs1);
bs2ActivitiesClient.executecommand6(date, resultODLSLBs2);
}
@Override
protected void doCatch(Throwable e){
System.out.println("Failed to execute BS2 daily job");
}
@Override
protected void doFinally(){
secondServerDone.set(null);
}
};
// AndPromise is done when all of its constructor parameters are done.
// I decided to consider the date processing done when both
// TryCatchFinallies are done. You can implement more complex logic depending on
// the business requirements. One option is to wrap both TryCatcFinallies
// in another TryCatchFinally.
return new AndPromise(firstServerDone, secondServerDone);
}
}