org.btrplace.plan.ReconfigurationPlanChecker Maven / Gradle / Ivy
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/*
* Copyright 2020 The BtrPlace Authors. All rights reserved.
* Use of this source code is governed by a LGPL-style
* license that can be found in the LICENSE.txt file.
*/
package org.btrplace.plan;
import org.btrplace.model.Model;
import org.btrplace.model.constraint.SatConstraint;
import org.btrplace.model.constraint.SatConstraintChecker;
import org.btrplace.plan.event.Action;
import org.btrplace.plan.event.ActionVisitor;
import org.btrplace.plan.event.Allocate;
import org.btrplace.plan.event.AllocateEvent;
import org.btrplace.plan.event.BootNode;
import org.btrplace.plan.event.BootVM;
import org.btrplace.plan.event.Event;
import org.btrplace.plan.event.ForgeVM;
import org.btrplace.plan.event.KillVM;
import org.btrplace.plan.event.MigrateVM;
import org.btrplace.plan.event.ResumeVM;
import org.btrplace.plan.event.ShutdownNode;
import org.btrplace.plan.event.ShutdownVM;
import org.btrplace.plan.event.SubstitutedVMEvent;
import org.btrplace.plan.event.SuspendVM;
import org.btrplace.scheduler.InconsistentSolutionException;
import java.util.ArrayList;
import java.util.List;
import java.util.PriorityQueue;
/**
* Checker to verify if a reconfiguration plan satisfies a set of
* {@link org.btrplace.model.constraint.SatConstraintChecker}.
*
* In practice, the origin model is send to each of the checkers.
* Then it notifies all the checkers for the beginning and the end moment of each of the actions and events.
* Finally, it sends the resulting model to each of the checkers.
*
* Actions start and end moment are notified in the increasing order of their associated moment with
* a priority given to the end moments.
*
* @author Fabien Hermenier
*/
public class ReconfigurationPlanChecker implements ActionVisitor {
private boolean startingEvent = true;
private static final TimedBasedActionComparator STARTS_CMP = new TimedBasedActionComparator(true, true);
private static final TimedBasedActionComparator ENDS_CMP = new TimedBasedActionComparator(false, true);
private final List> checkers;
/**
* Make a new instance.
*/
public ReconfigurationPlanChecker() {
checkers = new ArrayList<>();
}
/**
* Add an additional checker.
*
* @param c the checker to add
* @return {@code true} iff the checker has been added
*/
public boolean addChecker(SatConstraintChecker c) {
return checkers.add(c);
}
/**
* Remove a checker.
*
* @param c the checker to remove
* @return {@code true} iff the checker was present
*/
public boolean removeChecker(SatConstraintChecker c) {
return checkers.remove(c);
}
@Override
public SatConstraint visit(Allocate a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public Object visit(AllocateEvent a) {
for (SatConstraintChecker c : checkers) {
if (!c.consume(a)) {
return c.getConstraint();
}
}
return null;
}
@Override
public SatConstraint visit(SubstitutedVMEvent a) {
for (SatConstraintChecker c : checkers) {
if (!c.consume(a)) {
return c.getConstraint();
}
}
return null;
}
@Override
public SatConstraint visit(BootNode a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public SatConstraint visit(BootVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public SatConstraint visit(ForgeVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public SatConstraint visit(KillVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public SatConstraint visit(MigrateVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public Object visit(ResumeVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public Object visit(ShutdownNode a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public Object visit(ShutdownVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
@Override
public Object visit(SuspendVM a) {
for (SatConstraintChecker c : checkers) {
if (startingEvent) {
if (!c.start(a)) {
return c.getConstraint();
}
} else {
c.end(a);
}
}
return null;
}
/**
* Check if a plan satisfies all the {@link SatConstraintChecker}.
*
* @param p the plan to check
* @throws SatConstraintViolationException if a violation is detected
*/
public void check(ReconfigurationPlan p) throws SatConstraintViolationException {
if (checkers.isEmpty()) {
return;
}
checkModel(p.getOrigin(), true);
if (!p.getActions().isEmpty()) {
PriorityQueue starts = new PriorityQueue<>(p.getActions().size(), STARTS_CMP);
PriorityQueue ends = new PriorityQueue<>(p.getActions().size(), ENDS_CMP);
starts.addAll(p.getActions());
ends.addAll(p.getActions());
//Starts the actions
int curMoment = starts.peek().getStart();
while (!starts.isEmpty() || !ends.isEmpty()) {
Action a = ends.peek();
while (a != null && a.getEnd() == curMoment) {
ends.remove();
startingEvent = false;
visitAndThrowOnViolation(a);
visitEvents(a, Action.Hook.POST);
a = ends.peek();
}
a = starts.peek();
while (a != null && a.getStart() == curMoment) {
starts.remove();
startingEvent = true;
visitEvents(a, Action.Hook.PRE);
visitAndThrowOnViolation(a);
a = starts.peek();
}
int nextEnd = Integer.MAX_VALUE;
if (!ends.isEmpty()) {
nextEnd = ends.peek().getEnd();
}
int nextStart = Integer.MAX_VALUE;
if (!starts.isEmpty()) {
nextStart = starts.peek().getStart();
}
curMoment = Math.min(nextEnd, nextStart);
}
}
Model mo = p.getResult();
if (mo == null) {
throw new InconsistentSolutionException(p, "The resulting reconfiguration plan is not applyable");
}
checkModel(mo, false);
}
private void visitAndThrowOnViolation(Action a) throws SatConstraintViolationException {
SatConstraint c = (SatConstraint) a.visit(this);
if (c != null) {
throw new ContinuousViolationException(c, a);
}
}
private void visitEvents(Action a, Action.Hook k) throws SatConstraintViolationException {
SatConstraint c;
for (Event e : a.getEvents(k)) {
c = (SatConstraint) e.visit(this);
if (c != null) {
throw new ContinuousViolationException(c, a);
}
}
}
/**
* Check for the validity of a model.
*
* @param mo the model to check
* @param start {@code true} iff the model corresponds to the origin model. Otherwise it is considered
* to be the resulting model
* @throws SatConstraintViolationException if at least one constraint is violated.
*/
private void checkModel(Model mo, boolean start) throws SatConstraintViolationException {
for (SatConstraintChecker c : checkers) {
if (start && !c.startsWith(mo)) {
SatConstraint cs = c.getConstraint();
if (cs != null) {
throw new DiscreteViolationException(c.getConstraint(), mo);
}
} else if (!start && !c.endsWith(mo)) {
SatConstraint cs = c.getConstraint();
if (cs != null) {
throw new DiscreteViolationException(c.getConstraint(), mo);
}
}
}
}
}