Java tutorial
/* * 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.nosql.riak; import static org.apache.brooklyn.util.JavaGroovyEquivalents.groovyTruth; import java.net.URI; import java.util.Collection; import java.util.List; import java.util.Map; import org.apache.brooklyn.api.entity.Entity; import org.apache.brooklyn.api.entity.EntitySpec; import org.apache.brooklyn.api.policy.PolicySpec; import org.apache.brooklyn.api.sensor.AttributeSensor; import org.apache.brooklyn.api.sensor.EnricherSpec; import org.apache.brooklyn.core.entity.Attributes; import org.apache.brooklyn.core.entity.Entities; import org.apache.brooklyn.core.entity.EntityInternal; import org.apache.brooklyn.core.entity.EntityPredicates; import org.apache.brooklyn.core.entity.lifecycle.Lifecycle; import org.apache.brooklyn.core.entity.lifecycle.ServiceStateLogic; import org.apache.brooklyn.core.entity.lifecycle.ServiceStateLogic.ServiceNotUpLogic; import org.apache.brooklyn.core.entity.trait.Startable; import org.apache.brooklyn.core.sensor.DependentConfiguration; import org.apache.brooklyn.enricher.stock.Enrichers; import org.apache.brooklyn.entity.group.AbstractMembershipTrackingPolicy; import org.apache.brooklyn.entity.group.DynamicClusterImpl; import org.apache.brooklyn.util.core.task.Tasks; import org.apache.brooklyn.util.time.Duration; import org.apache.brooklyn.util.time.Time; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.google.common.base.Function; import com.google.common.base.Joiner; import com.google.common.base.Optional; import com.google.common.base.Preconditions; import com.google.common.base.Predicates; import com.google.common.collect.ImmutableMap; import com.google.common.collect.ImmutableSet; import com.google.common.collect.Iterables; import com.google.common.collect.Lists; import com.google.common.collect.Maps; public class RiakClusterImpl extends DynamicClusterImpl implements RiakCluster { private static final Logger log = LoggerFactory.getLogger(RiakClusterImpl.class); private transient Object mutex = new Object[0]; public void init() { super.init(); log.info("Initializing the riak cluster..."); sensors().set(IS_CLUSTER_INIT, false); } @Override protected void doStart() { super.doStart(); connectSensors(); try { Duration delay = getConfig(DELAY_BEFORE_ADVERTISING_CLUSTER); Tasks.setBlockingDetails("Sleeping for " + delay + " before advertising cluster available"); Time.sleep(delay); } finally { Tasks.resetBlockingDetails(); } //FIXME: add a quorum to tolerate failed nodes before setting on fire. @SuppressWarnings("unchecked") Optional<Entity> anyNode = Iterables.tryFind(getMembers(), Predicates.and(Predicates.instanceOf(RiakNode.class), EntityPredicates.attributeEqualTo(RiakNode.RIAK_NODE_HAS_JOINED_CLUSTER, true), EntityPredicates.attributeEqualTo(RiakNode.SERVICE_UP, true))); if (anyNode.isPresent()) { sensors().set(IS_CLUSTER_INIT, true); } else { log.warn("No Riak Nodes are found on the cluster: {}. Initialization Failed", getId()); ServiceStateLogic.setExpectedState(this, Lifecycle.ON_FIRE); } } protected EntitySpec<?> getMemberSpec() { EntitySpec<?> result = config().get(MEMBER_SPEC); if (result != null) return result; return EntitySpec.create(RiakNode.class); } protected void connectSensors() { policies().add(PolicySpec.create(MemberTrackingPolicy.class).displayName("Controller targets tracker") .configure("sensorsToTrack", ImmutableSet.of(RiakNode.SERVICE_UP)).configure("group", this)); EnricherSpec<?> first = Enrichers.builder().aggregating(Attributes.MAIN_URI).publishing(Attributes.MAIN_URI) .computing(new Function<Collection<URI>, URI>() { @Override public URI apply(Collection<URI> input) { return input.iterator().next(); } }).fromMembers().build(); enrichers().add(first); Map<? extends AttributeSensor<? extends Number>, ? extends AttributeSensor<? extends Number>> enricherSetup = ImmutableMap .<AttributeSensor<? extends Number>, AttributeSensor<? extends Number>>builder() .put(RiakNode.NODE_PUTS, RiakCluster.NODE_PUTS_1MIN_PER_NODE) .put(RiakNode.NODE_GETS, RiakCluster.NODE_GETS_1MIN_PER_NODE) .put(RiakNode.NODE_OPS, RiakCluster.NODE_OPS_1MIN_PER_NODE).build(); // construct sum and average over cluster for (AttributeSensor<? extends Number> nodeSensor : enricherSetup.keySet()) { addSummingMemberEnricher(nodeSensor); addAveragingMemberEnricher(nodeSensor, enricherSetup.get(nodeSensor)); } } private void addAveragingMemberEnricher(AttributeSensor<? extends Number> fromSensor, AttributeSensor<? extends Number> toSensor) { enrichers().add(Enrichers.builder().aggregating(fromSensor).publishing(toSensor).fromMembers() .computingAverage().build()); } private void addSummingMemberEnricher(AttributeSensor<? extends Number> source) { enrichers().add( Enrichers.builder().aggregating(source).publishing(source).fromMembers().computingSum().build()); } protected void onServerPoolMemberChanged(final Entity member) { synchronized (mutex) { log.trace("For {}, considering membership of {} which is in locations {}", new Object[] { this, member, member.getLocations() }); Map<Entity, String> nodes = getAttribute(RIAK_CLUSTER_NODES); if (belongsInServerPool(member)) { // TODO can we discover the nodes by asking the riak cluster, rather than assuming what we add will be in there? // TODO and can we do join as part of node starting? if (nodes == null) { nodes = Maps.newLinkedHashMap(); } String riakName = getRiakName(member); Preconditions.checkNotNull(riakName); // flag a first node to be the first node in the riak cluster. Boolean firstNode = getAttribute(IS_FIRST_NODE_SET); if (!Boolean.TRUE.equals(firstNode)) { sensors().set(IS_FIRST_NODE_SET, Boolean.TRUE); nodes.put(member, riakName); sensors().set(RIAK_CLUSTER_NODES, nodes); ((EntityInternal) member).sensors().set(RiakNode.RIAK_NODE_HAS_JOINED_CLUSTER, Boolean.TRUE); log.info("Added initial Riak node {}: {}; {} to new cluster", new Object[] { this, member, getRiakName(member) }); } else { // TODO: be wary of erroneous nodes but are still flagged 'in cluster' // add the new node to be part of the riak cluster. Optional<Entity> anyNodeInCluster = Iterables.tryFind(nodes.keySet(), Predicates.and( Predicates.instanceOf(RiakNode.class), EntityPredicates.attributeEqualTo(RiakNode.RIAK_NODE_HAS_JOINED_CLUSTER, true))); if (anyNodeInCluster.isPresent()) { if (!nodes.containsKey(member) && member.getAttribute(RiakNode.RIAK_NODE_HAS_JOINED_CLUSTER) == null) { String anyNodeName = anyNodeInCluster.get().getAttribute(RiakNode.RIAK_NODE_NAME); Entities.invokeEffectorWithArgs(this, member, RiakNode.JOIN_RIAK_CLUSTER, anyNodeName) .blockUntilEnded(); nodes.put(member, riakName); sensors().set(RIAK_CLUSTER_NODES, nodes); log.info("Added Riak node {}: {}; {} to cluster", new Object[] { this, member, getRiakName(member) }); } } else { log.error("isFirstNodeSet, but no cluster members found to add {}", member.getId()); } } } else { if (nodes != null && nodes.containsKey(member)) { DependentConfiguration.attributeWhenReady(member, RiakNode.RIAK_NODE_HAS_JOINED_CLUSTER, Predicates.equalTo(false)).blockUntilEnded(Duration.TWO_MINUTES); @SuppressWarnings("unchecked") Optional<Entity> anyNodeInCluster = Iterables.tryFind(nodes.keySet(), Predicates.and(Predicates.instanceOf(RiakNode.class), EntityPredicates.attributeEqualTo(RiakNode.RIAK_NODE_HAS_JOINED_CLUSTER, true), Predicates.not(Predicates.equalTo(member)))); if (anyNodeInCluster.isPresent()) { Entities.invokeEffectorWithArgs(this, anyNodeInCluster.get(), RiakNode.REMOVE_FROM_CLUSTER, getRiakName(member)).blockUntilEnded(); } nodes.remove(member); sensors().set(RIAK_CLUSTER_NODES, nodes); log.info("Removed Riak node {}: {}; {} from cluster", new Object[] { this, member, getRiakName(member) }); } } ServiceNotUpLogic.updateNotUpIndicatorRequiringNonEmptyMap(this, RIAK_CLUSTER_NODES); calculateClusterAddresses(); } } private void calculateClusterAddresses() { List<String> addresses = Lists.newArrayList(); List<String> addressesPbPort = Lists.newArrayList(); for (Entity entity : this.getMembers()) { if (entity instanceof RiakNode && entity.getAttribute(Attributes.SERVICE_UP)) { RiakNode riakNode = (RiakNode) entity; addresses.add(riakNode.getAttribute(Attributes.SUBNET_HOSTNAME) + ":" + riakNode.getAttribute(RiakNode.RIAK_WEB_PORT)); addressesPbPort.add(riakNode.getAttribute(Attributes.SUBNET_HOSTNAME) + ":" + riakNode.getAttribute(RiakNode.RIAK_PB_PORT)); } } sensors().set(RiakCluster.NODE_LIST, Joiner.on(",").join(addresses)); sensors().set(RiakCluster.NODE_LIST_PB_PORT, Joiner.on(",").join(addressesPbPort)); } protected boolean belongsInServerPool(Entity member) { if (!groovyTruth(member.getAttribute(Startable.SERVICE_UP))) { log.trace("Members of {}, checking {}, eliminating because not up", this, member); return false; } if (!getMembers().contains(member)) { log.trace("Members of {}, checking {}, eliminating because not member", this, member); return false; } log.trace("Members of {}, checking {}, approving", this, member); return true; } private String getRiakName(Entity node) { return node.getAttribute(RiakNode.RIAK_NODE_NAME); } public static class MemberTrackingPolicy extends AbstractMembershipTrackingPolicy { @Override protected void onEntityEvent(EventType type, Entity entity) { ((RiakClusterImpl) super.entity).onServerPoolMemberChanged(entity); } } }