/*
*
* Copyright 2012 Netflix, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package com.netflix.simianarmy.basic.janitor;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.netflix.simianarmy.Resource;
import com.netflix.simianarmy.janitor.JanitorRuleEngine;
import com.netflix.simianarmy.janitor.Rule;
/**
* Basic implementation of janitor rule engine that runs all containing rules to decide if a resource should be
* a candidate of cleanup.
*/
public class BasicJanitorRuleEngine implements JanitorRuleEngine {
/** The Constant LOGGER. */
private static final Logger LOGGER = LoggerFactory.getLogger(BasicJanitorRuleEngine.class);
/** The rules to decide if a resource should be a candidate for cleanup. **/
private final List<Rule> rules;
/**
* The constructor of JanitorRuleEngine.
*/
public BasicJanitorRuleEngine() {
rules = new ArrayList<Rule>();
}
/**
* Decides whether the resource should be a candidate of cleanup based on the underlying rules. If any rule in the
* rule set thinks the resource should be a candidate of cleanup, the method returns false which indicates that the
* resource should be marked for cleanup. If multiple rules think the resource should be cleaned up, the rule with
* the nearest expected termination time fills the termination reason and expected termination time.
*
* @param resource
* The resource
* @return true if the resource is valid and should not be a candidate of cleanup based on the underlying rules,
* false otherwise.
*/
@Override
public boolean isValid(Resource resource) {
LOGGER.debug(String.format("Checking if resource %s of type %s is a cleanup candidate against %d rules.",
resource.getId(), resource.getResourceType(), rules.size()));
// We create a clone of the resource each time when we try the rule. In the first iteration of the rules
// we identify the rule with the nearest termination date if there is any rule considers the resource
// as a cleanup candidate. Then the rule is applied to the original resource.
Rule nearestRule = null;
if (rules.size() == 1) {
nearestRule = rules.get(0);
} else {
Date nearestTerminationTime = null;
for (Rule rule : rules) {
Resource clone = resource.cloneResource();
if (!rule.isValid(clone) && (nearestTerminationTime == null
|| nearestTerminationTime.after(clone.getExpectedTerminationTime()))) {
nearestRule = rule;
nearestTerminationTime = clone.getExpectedTerminationTime();
}
}
}
if (nearestRule != null && !nearestRule.isValid(resource)) {
LOGGER.info(String.format("Resource %s is marked as a cleanup candidate.", resource.getId()));
return false;
} else {
LOGGER.info(String.format("Resource %s is not marked as a cleanup candidate.", resource.getId()));
return true;
}
}
/** {@inheritDoc} */
@Override
public BasicJanitorRuleEngine addRule(Rule rule) {
rules.add(rule);
return this;
}
}