/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.brooklyn.entity.messaging.kafka;
import java.util.Collection;
import java.util.List;
import org.apache.brooklyn.api.entity.Entity;
import org.apache.brooklyn.api.entity.EntitySpec;
import org.apache.brooklyn.api.location.Location;
import org.apache.brooklyn.core.entity.AbstractEntity;
import org.apache.brooklyn.core.entity.Entities;
import org.apache.brooklyn.core.entity.trait.Startable;
import org.apache.brooklyn.core.feed.ConfigToAttributes;
import org.apache.brooklyn.core.location.Locations;
import org.apache.brooklyn.enricher.stock.Enrichers;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.brooklyn.entity.group.DynamicCluster;
import org.apache.brooklyn.entity.zookeeper.ZooKeeperNode;
import org.apache.brooklyn.util.collections.MutableList;
import org.apache.brooklyn.util.exceptions.CompoundRuntimeException;
import com.google.common.base.Objects;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
/**
* Implementation of a Kafka cluster containing a {@link KafkaZookeeper} node and a group of {@link KafkaBroker}s.
*/
public class KafkaClusterImpl extends AbstractEntity implements KafkaCluster {
public static final Logger log = LoggerFactory.getLogger(KafkaClusterImpl.class);
public KafkaClusterImpl() {
}
@Override
public void init() {
super.init();
sensors().set(SERVICE_UP, false);
ConfigToAttributes.apply(this, BROKER_SPEC);
ConfigToAttributes.apply(this, ZOOKEEPER);
ConfigToAttributes.apply(this, ZOOKEEPER_SPEC);
log.debug("creating zookeeper child for {}", this);
ZooKeeperNode zookeeper = getAttribute(ZOOKEEPER);
if (zookeeper == null) {
EntitySpec<KafkaZooKeeper> zookeeperSpec = getAttribute(ZOOKEEPER_SPEC);
if (zookeeperSpec == null) {
log.debug("creating zookeeper using default spec for {}", this);
zookeeperSpec = EntitySpec.create(KafkaZooKeeper.class);
sensors().set(ZOOKEEPER_SPEC, zookeeperSpec);
} else {
log.debug("creating zookeeper using custom spec for {}", this);
}
zookeeper = addChild(zookeeperSpec);
sensors().set(ZOOKEEPER, zookeeper);
}
log.debug("creating cluster child for {}", this);
EntitySpec<KafkaBroker> brokerSpec = getAttribute(BROKER_SPEC);
if (brokerSpec == null) {
log.debug("creating default broker spec for {}", this);
brokerSpec = EntitySpec.create(KafkaBroker.class);
sensors().set(BROKER_SPEC, brokerSpec);
}
// Relies on initialSize being inherited by DynamicCluster, because key id is identical
// We add the zookeeper configuration to the KafkaBroker specification here
DynamicCluster cluster = addChild(EntitySpec.create(DynamicCluster.class)
.configure("memberSpec", EntitySpec.create(brokerSpec).configure(KafkaBroker.ZOOKEEPER, zookeeper)));
sensors().set(CLUSTER, cluster);
connectSensors();
}
@Override
public ZooKeeperNode getZooKeeper() {
return getAttribute(ZOOKEEPER);
}
@Override
public DynamicCluster getCluster() {
return getAttribute(CLUSTER);
}
@Override
public void start(Collection<? extends Location> locations) {
if (isLegacyConstruction()) {
// TODO should no longer be needed?
init();
}
locations = MutableList.copyOf(Locations.getLocationsCheckingAncestors(locations, this));
Iterables.getOnlyElement(locations); // Assert just one
// set it; here we don't allow changing locations
addLocations(locations);
List<Entity> childrenToStart = MutableList.<Entity>of(getCluster());
// Set the KafkaZookeeper entity as child of cluster, if it does not already have a parent
if (getZooKeeper().getParent() == null) {
addChild(getZooKeeper());
} // And only start zookeeper if we are parent
if (Objects.equal(this, getZooKeeper().getParent())) childrenToStart.add(getZooKeeper());
Entities.invokeEffector(this, childrenToStart, Startable.START, ImmutableMap.of("locations", locations)).getUnchecked();
}
@Override
public void stop() {
List<Exception> errors = Lists.newArrayList();
if (getZooKeeper() != null && Objects.equal(this, getZooKeeper().getParent())) {
try {
getZooKeeper().stop();
} catch (Exception e) {
errors.add(e);
}
}
if (getCurrentSize() > 0) {
try {
getCluster().stop();
} catch (Exception e) {
errors.add(e);
}
}
clearLocations();
sensors().set(SERVICE_UP, false);
if (errors.size() != 0) {
throw new CompoundRuntimeException("Error stopping Kafka cluster", errors);
}
}
@Override
public void restart() {
// TODO prod the entities themselves to restart, instead?
Collection<Location> locations = Lists.newArrayList(getLocations());
stop();
start(locations);
}
void connectSensors() {
enrichers().add(Enrichers.builder()
.propagatingAllBut(SERVICE_UP)
.from(getCluster())
.build());
enrichers().add(Enrichers.builder()
.propagating(SERVICE_UP)
.from(getZooKeeper())
.build());
}
/*
* All Group and Resizable interface methods are delegated to the broker cluster.
*/
/** {@inheritDoc} */
@Override
public Collection<Entity> getMembers() { return getCluster().getMembers(); }
/** {@inheritDoc} */
@Override
public boolean hasMember(Entity member) { return getCluster().hasMember(member); }
/** {@inheritDoc} */
@Override
public boolean addMember(Entity member) { return getCluster().addMember(member); }
/** {@inheritDoc} */
@Override
public boolean removeMember(Entity member) { return getCluster().removeMember(member); }
/** {@inheritDoc} */
@Override
public Integer getCurrentSize() { return getCluster().getCurrentSize(); }
/** {@inheritDoc} */
@Override
public Integer resize(Integer desiredSize) { return getCluster().resize(desiredSize); }
@Override
public <T extends Entity> T addMemberChild(EntitySpec<T> spec) { return getCluster().addMemberChild(spec); }
@Override
public <T extends Entity> T addMemberChild(T child) { return getCluster().addMemberChild(child); }
}