/*
*
* 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.aws.janitor.rule.asg;
import java.util.List;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.Validate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.netflix.appinfo.InstanceInfo;
import com.netflix.appinfo.InstanceInfo.InstanceStatus;
import com.netflix.discovery.DiscoveryClient;
import com.netflix.simianarmy.Resource;
import com.netflix.simianarmy.aws.janitor.crawler.ASGJanitorCrawler;
/**
* The class is for checking whether an ASG has any active instance using Discovery/Eureka.
* If Discovery/Eureka is enabled, it uses its service to check if the instances in the ASG are
* registered and up there.
*/
public class DiscoveryASGInstanceValidator implements ASGInstanceValidator {
/** The Constant LOGGER. */
private static final Logger LOGGER = LoggerFactory.getLogger(DiscoveryASGInstanceValidator.class);
private final DiscoveryClient discoveryClient;
/**
* Constructor.
* @param discoveryClient
* the client to access the Discovery/Eureka service for checking the status of instances.
*/
public DiscoveryASGInstanceValidator(DiscoveryClient discoveryClient) {
Validate.notNull(discoveryClient);
this.discoveryClient = discoveryClient;
}
/** {@inheritDoc} */
@Override
public boolean hasActiveInstance(Resource resource) {
String instanceIds = resource.getAdditionalField(ASGJanitorCrawler.ASG_FIELD_INSTANCES);
String maxSizeStr = resource.getAdditionalField(ASGJanitorCrawler.ASG_FIELD_MAX_SIZE);
if (StringUtils.isBlank(instanceIds)) {
if (maxSizeStr != null && Integer.parseInt(maxSizeStr) == 0) {
// The ASG is empty when it has no instance and the max size of the ASG is 0.
// If the max size is not 0, the ASG could probably be in the process of starting new instances.
LOGGER.info(String.format("ASG %s is empty.", resource.getId()));
return false;
} else {
LOGGER.info(String.format("ASG %s does not have instances but the max size is %s",
resource.getId(), maxSizeStr));
return true;
}
}
String[] instances = StringUtils.split(instanceIds, ",");
LOGGER.debug(String.format("Checking if the %d instances in ASG %s are active.",
instances.length, resource.getId()));
for (String instanceId : instances) {
if (isActiveInstance(instanceId)) {
LOGGER.info(String.format("ASG %s has active instance.", resource.getId()));
return true;
}
}
LOGGER.info(String.format("ASG %s has no active instance.", resource.getId()));
return false;
}
/**
* Returns true if the instance is registered in Eureka/Discovery.
* @param instanceId the instance id
* @return true if the instance is active, false otherwise
*/
private boolean isActiveInstance(String instanceId) {
Validate.notNull(instanceId);
LOGGER.debug(String.format("Checking if instance %s is active", instanceId));
List<InstanceInfo> instanceInfos = discoveryClient.getInstancesById(instanceId);
for (InstanceInfo info : instanceInfos) {
InstanceStatus status = info.getStatus();
if (status == InstanceStatus.UP || status == InstanceStatus.STARTING) {
LOGGER.debug(String.format("Instance %s is active in Discovery.", instanceId));
return true;
}
}
LOGGER.debug(String.format("Instance %s is not active in Discovery.", instanceId));
return false;
}
}