/*
*
* 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;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import com.google.common.collect.Maps;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.amazonaws.services.ec2.model.Instance;
import com.amazonaws.services.ec2.model.Tag;
import com.amazonaws.services.ec2.model.Volume;
import com.amazonaws.services.ec2.model.VolumeAttachment;
import com.netflix.simianarmy.EventType;
import com.netflix.simianarmy.Monkey;
import com.netflix.simianarmy.MonkeyCalendar;
import com.netflix.simianarmy.MonkeyConfiguration;
import com.netflix.simianarmy.MonkeyRecorder.Event;
import com.netflix.simianarmy.MonkeyType;
import com.netflix.simianarmy.aws.AWSResource;
import com.netflix.simianarmy.client.aws.AWSClient;
import com.netflix.simianarmy.janitor.JanitorMonkey;
/**
* A companion monkey of Janitor Monkey for tagging EBS volumes with the last attachment information.
* In many scenarios, EBS volumes generated by applications remain unattached to instances. Amazon
* does not keep track of last unattached time, which makes it difficult to determine its usage.
* To solve this, this monkey will tag all EBS volumes with last owner and instance to which they are attached
* and the time they got detached from instance. The monkey will poll and monitor EBS volumes hourly (by default).
*
*/
public class VolumeTaggingMonkey extends Monkey {
/** The Constant LOGGER. */
private static final Logger LOGGER = LoggerFactory.getLogger(VolumeTaggingMonkey.class);
/**
* The Interface Context.
*/
public interface Context extends Monkey.Context {
/**
* Configuration.
*
* @return the monkey configuration
*/
@Override
MonkeyConfiguration configuration();
/**
* AWS clients. Using a collection of clients for supporting running one monkey for multiple regions.
*
* @return the collection of AWS clients
*/
Collection<AWSClient> awsClients();
}
private final MonkeyConfiguration config;
private final Collection<AWSClient> awsClients;
private final MonkeyCalendar calendar;
/** We cache the global map from instance id to its owner when starting the monkey. */
private final Map<AWSClient, Map<String, String>> awsClientToInstanceToOwner;
/**
* The constructor.
* @param ctx the context
*/
public VolumeTaggingMonkey(Context ctx) {
super(ctx);
this.config = ctx.configuration();
this.awsClients = ctx.awsClients();
this.calendar = ctx.calendar();
awsClientToInstanceToOwner = Maps.newHashMap();
for (AWSClient awsClient : awsClients) {
Map<String, String> instanceToOwner = Maps.newHashMap();
awsClientToInstanceToOwner.put(awsClient, instanceToOwner);
for (Instance instance : awsClient.describeInstances()) {
for (Tag tag : instance.getTags()) {
if (tag.getKey().equals(JanitorMonkey.OWNER_TAG_KEY)) {
instanceToOwner.put(instance.getInstanceId(), tag.getValue());
}
}
}
}
}
/**
* The monkey Type.
*/
public enum Type implements MonkeyType {
/** Volume tagging monkey. */
VOLUME_TAGGING
}
/**
* The event types that this monkey causes.
*/
public enum EventTypes implements EventType {
/** The event type for tagging the volume with Janitor meta data information. */
TAGGING_JANITOR
}
@Override
public Type type() {
return Type.VOLUME_TAGGING;
}
@Override
public void doMonkeyBusiness() {
String prop = "simianarmy.volumeTagging.enabled";
if (config.getBoolOrElse(prop, false)) {
for (AWSClient awsClient : awsClients) {
tagVolumesWithLatestAttachment(awsClient);
}
} else {
LOGGER.info(String.format("Volume tagging monkey is not enabled. You can set %s to true to enable it.",
prop));
}
}
private void tagVolumesWithLatestAttachment(AWSClient awsClient) {
List<Volume> volumes = awsClient.describeVolumes();
LOGGER.info(String.format("Trying to tag %d volumes for Janitor Monkey meta data.",
volumes.size()));
Date now = calendar.now().getTime();
for (Volume volume : volumes) {
String owner = null, instanceId = null;
Date lastDetachTime = null;
List<VolumeAttachment> attachments = volume.getAttachments();
List<Tag> tags = volume.getTags();
// The volume can have a special tag is it does not want to be changed/tagged
// by Janitor monkey.
if ("donotmark".equals(getTagValue(JanitorMonkey.JANITOR_TAG, tags))) {
LOGGER.info(String.format("The volume %s is tagged as not handled by Janitor",
volume.getVolumeId()));
continue;
}
Map<String, String> janitorMetadata = parseJanitorTag(tags);
// finding the instance attached most recently.
VolumeAttachment latest = null;
for (VolumeAttachment attachment : attachments) {
if (latest == null || latest.getAttachTime().before(attachment.getAttachTime())) {
latest = attachment;
}
}
if (latest != null) {
instanceId = latest.getInstanceId();
owner = getOwnerEmail(instanceId, janitorMetadata, tags, awsClient);
}
if (latest == null || "detached".equals(latest.getState())) {
if (janitorMetadata.get(JanitorMonkey.DETACH_TIME_TAG_KEY) == null) {
// There is no attached instance and the last detached time is not set.
// Use the current time as the last detached time.
LOGGER.info(String.format("Setting the last detached time to %s for volume %s",
now, volume.getVolumeId()));
lastDetachTime = now;
} else {
LOGGER.debug(String.format("The volume %s was already marked as detached at time %s",
volume.getVolumeId(), janitorMetadata.get(JanitorMonkey.DETACH_TIME_TAG_KEY)));
}
} else {
// The volume is currently attached to an instance
lastDetachTime = null;
}
String existingOwner = janitorMetadata.get(JanitorMonkey.OWNER_TAG_KEY);
if (owner == null && existingOwner != null) {
// Save the current owner in the tag when we are not able to find a owner.
owner = existingOwner;
}
if (needsUpdate(janitorMetadata, owner, instanceId, lastDetachTime)) {
Event evt = updateJanitorMetaTag(volume, instanceId, owner, lastDetachTime, awsClient);
if (evt != null) {
context().recorder().recordEvent(evt);
}
}
}
}
private String getOwnerEmail(String instanceId, Map<String, String> janitorMetadata,
List<Tag> tags, AWSClient awsClient) {
// The owner of the volume is set as the owner of the last instance attached to it.
String owner = awsClientToInstanceToOwner.get(awsClient).get(instanceId);
if (owner == null) {
owner = janitorMetadata.get(JanitorMonkey.OWNER_TAG_KEY);
}
if (owner == null) {
owner = getTagValue(JanitorMonkey.OWNER_TAG_KEY, tags);
}
String emailDomain = getOwnerEmailDomain();
if (owner != null && !owner.contains("@")
&& StringUtils.isNotBlank(emailDomain)) {
owner = String.format("%s@%s", owner, emailDomain);
}
return owner;
}
/**
* Parses the Janitor meta tag set by this monkey and gets a map from key
* to value for the tag values.
* @param tags the tags of the volumes
* @return the map from the Janitor meta tag key to value
*/
private static Map<String, String> parseJanitorTag(List<Tag> tags) {
String janitorTag = getTagValue(JanitorMonkey.JANITOR_META_TAG, tags);
return parseJanitorMetaTag(janitorTag);
}
/**
* Parses the string of Janitor meta-data tag value to get a key value map.
* @param janitorMetaTag the value of the Janitor meta-data tag
* @return the key value map in the Janitor meta-data tag
*/
public static Map<String, String> parseJanitorMetaTag(String janitorMetaTag) {
Map<String, String> metadata = new HashMap<String, String>();
if (janitorMetaTag != null) {
for (String keyValue : janitorMetaTag.split(";")) {
String[] meta = keyValue.split("=");
if (meta.length == 2) {
metadata.put(meta[0], meta[1]);
}
}
}
return metadata;
}
/** Gets the domain name for the owner email. The method can be overridden in subclasses.
*
* @return the domain name for the owner email.
*/
protected String getOwnerEmailDomain() {
return config.getStrOrElse("simianarmy.volumeTagging.ownerEmailDomain", "");
}
private Event updateJanitorMetaTag(Volume volume, String instance, String owner, Date lastDetachTime,
AWSClient awsClient) {
String meta = makeMetaTag(instance, owner, lastDetachTime);
Map<String, String> janitorTags = new HashMap<String, String>();
janitorTags.put(JanitorMonkey.JANITOR_META_TAG, meta);
LOGGER.info(String.format("Setting tag %s to '%s' for volume %s",
JanitorMonkey.JANITOR_META_TAG, meta, volume.getVolumeId()));
String prop = "simianarmy.volumeTagging.leashed";
Event evt = null;
if (config.getBoolOrElse(prop, true)) {
LOGGER.info("Volume tagging monkey is leashed. No real change is made to the volume.");
} else {
try {
awsClient.createTagsForResources(janitorTags, volume.getVolumeId());
evt = context().recorder().newEvent(type(), EventTypes.TAGGING_JANITOR,
awsClient.region(), volume.getVolumeId());
evt.addField(JanitorMonkey.JANITOR_META_TAG, meta);
} catch (Exception e) {
LOGGER.error(String.format("Failed to update the tag for volume %s", volume.getVolumeId()));
}
}
return evt;
}
/**
* Makes the Janitor meta tag for volumes to track the last attachment/detachment information.
* The method is intentionally made public for testing.
* @param instance the last attached instance
* @param owner the last owner
* @param lastDetachTime the detach time
* @return the meta tag of Janitor Monkey
*/
public static String makeMetaTag(String instance, String owner, Date lastDetachTime) {
StringBuilder meta = new StringBuilder();
meta.append(String.format("%s=%s;",
JanitorMonkey.INSTANCE_TAG_KEY, instance == null ? "" : instance));
meta.append(String.format("%s=%s;", JanitorMonkey.OWNER_TAG_KEY, owner == null ? "" : owner));
meta.append(String.format("%s=%s", JanitorMonkey.DETACH_TIME_TAG_KEY,
lastDetachTime == null ? "" : AWSResource.DATE_FORMATTER.print(lastDetachTime.getTime())));
return meta.toString();
}
private static String getTagValue(String key, List<Tag> tags) {
for (Tag tag : tags) {
if (tag.getKey().equals(key)) {
return tag.getValue();
}
}
return null;
}
/** Needs to update tags of the volume if
* 1) owner or instance attached changed or
* 2) the last detached status is changed.
*/
private static boolean needsUpdate(Map<String, String> metadata,
String owner, String instance, Date lastDetachTime) {
return (owner != null && !StringUtils.equals(metadata.get(JanitorMonkey.OWNER_TAG_KEY), owner))
|| (instance != null && !StringUtils.equals(metadata.get(JanitorMonkey.INSTANCE_TAG_KEY), instance))
|| lastDetachTime != null;
}
}