Java tutorial
/* * Copyright 2015 Open Networking Laboratory * * 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 org.onosproject.store.intent.impl; import com.google.common.collect.ImmutableList; import org.apache.commons.lang.math.RandomUtils; import org.apache.felix.scr.annotations.Activate; import org.apache.felix.scr.annotations.Component; import org.apache.felix.scr.annotations.Deactivate; import org.apache.felix.scr.annotations.Reference; import org.apache.felix.scr.annotations.ReferenceCardinality; import org.apache.felix.scr.annotations.Service; import org.onlab.util.KryoNamespace; import org.onosproject.cluster.ClusterService; import org.onosproject.cluster.ControllerNode; import org.onosproject.cluster.NodeId; import org.onosproject.net.intent.Intent; import org.onosproject.net.intent.IntentData; import org.onosproject.net.intent.IntentEvent; import org.onosproject.net.intent.IntentState; import org.onosproject.net.intent.IntentStore; import org.onosproject.net.intent.IntentStoreDelegate; import org.onosproject.net.intent.Key; import org.onosproject.net.intent.PartitionService; import org.onosproject.store.AbstractStore; import org.onosproject.store.service.MultiValuedTimestamp; import org.onosproject.store.service.WallClockTimestamp; import org.onosproject.store.serializers.KryoNamespaces; import org.onosproject.store.service.EventuallyConsistentMap; import org.onosproject.store.service.EventuallyConsistentMapEvent; import org.onosproject.store.service.EventuallyConsistentMapListener; import org.onosproject.store.service.StorageService; import org.slf4j.Logger; import java.util.Collection; import java.util.List; import java.util.Objects; import java.util.concurrent.atomic.AtomicLong; import java.util.stream.Collectors; import static com.google.common.base.Preconditions.checkNotNull; import static org.onosproject.net.intent.IntentState.PURGE_REQ; import static org.slf4j.LoggerFactory.getLogger; /** * Manages inventory of Intents in a distributed data store that uses optimistic * replication and gossip based techniques. */ //FIXME we should listen for leadership changes. if the local instance has just // ... become a leader, scan the pending map and process those @Component(immediate = true, enabled = true) @Service public class GossipIntentStore extends AbstractStore<IntentEvent, IntentStoreDelegate> implements IntentStore { private final Logger log = getLogger(getClass()); // Map of intent key => current intent state private EventuallyConsistentMap<Key, IntentData> currentMap; // Map of intent key => pending intent operation private EventuallyConsistentMap<Key, IntentData> pendingMap; @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) protected ClusterService clusterService; @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) protected StorageService storageService; @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) protected PartitionService partitionService; private final AtomicLong sequenceNumber = new AtomicLong(0); @Activate public void activate() { KryoNamespace.Builder intentSerializer = KryoNamespace.newBuilder().register(KryoNamespaces.API) .register(IntentData.class).register(MultiValuedTimestamp.class).register(WallClockTimestamp.class); currentMap = storageService.<Key, IntentData>eventuallyConsistentMapBuilder().withName("intent-current") .withSerializer(intentSerializer) .withTimestampProvider((key, intentData) -> new MultiValuedTimestamp<>(intentData.version(), sequenceNumber.getAndIncrement())) .withPeerUpdateFunction((key, intentData) -> getPeerNodes(key, intentData)).build(); pendingMap = storageService.<Key, IntentData>eventuallyConsistentMapBuilder().withName("intent-pending") .withSerializer(intentSerializer) .withTimestampProvider( (key, intentData) -> new MultiValuedTimestamp<>(intentData.version(), System.nanoTime())) .withPeerUpdateFunction((key, intentData) -> getPeerNodes(key, intentData)).build(); currentMap.addListener(new InternalCurrentListener()); pendingMap.addListener(new InternalPendingListener()); log.info("Started"); } @Deactivate public void deactivate() { currentMap.destroy(); pendingMap.destroy(); log.info("Stopped"); } @Override public long getIntentCount() { return currentMap.size(); } @Override public Iterable<Intent> getIntents() { return currentMap.values().stream().map(IntentData::intent).collect(Collectors.toList()); } @Override public Iterable<IntentData> getIntentData(boolean localOnly, long olderThan) { if (localOnly || olderThan > 0) { long now = System.currentTimeMillis(); final WallClockTimestamp time = new WallClockTimestamp(now - olderThan); return currentMap.values().stream() .filter(data -> data.version().isOlderThan(time) && (!localOnly || isMaster(data.key()))) .collect(Collectors.toList()); } return currentMap.values(); } @Override public IntentState getIntentState(Key intentKey) { IntentData data = currentMap.get(intentKey); if (data != null) { return data.state(); } return null; } @Override public List<Intent> getInstallableIntents(Key intentKey) { IntentData data = currentMap.get(intentKey); if (data != null) { return data.installables(); } return null; } @Override public void write(IntentData newData) { checkNotNull(newData); IntentData currentData = currentMap.get(newData.key()); if (IntentData.isUpdateAcceptable(currentData, newData)) { // Only the master is modifying the current state. Therefore assume // this always succeeds if (newData.state() == PURGE_REQ) { currentMap.remove(newData.key(), currentData); } else { currentMap.put(newData.key(), new IntentData(newData)); } // if current.put succeeded pendingMap.remove(newData.key(), newData); } } private Collection<NodeId> getPeerNodes(Key key, IntentData data) { NodeId master = partitionService.getLeader(key); NodeId origin = (data != null) ? data.origin() : null; if (data != null && (master == null || origin == null)) { log.debug("Intent {} missing master and/or origin; master = {}, origin = {}", key, master, origin); } NodeId me = clusterService.getLocalNode().id(); boolean isMaster = Objects.equals(master, me); boolean isOrigin = Objects.equals(origin, me); if (isMaster && isOrigin) { return getRandomNode(); } else if (isMaster) { return origin != null ? ImmutableList.of(origin) : getRandomNode(); } else if (isOrigin) { return master != null ? ImmutableList.of(master) : getRandomNode(); } else { log.warn("No master or origin for intent {}", key); return master != null ? ImmutableList.of(master) : getRandomNode(); } } private List<NodeId> getRandomNode() { NodeId me = clusterService.getLocalNode().id(); List<NodeId> nodes = clusterService.getNodes().stream().map(ControllerNode::id) .filter(node -> !Objects.equals(node, me)).collect(Collectors.toList()); if (nodes.size() == 0) { return null; } return ImmutableList.of(nodes.get(RandomUtils.nextInt(nodes.size()))); } @Override public void batchWrite(Iterable<IntentData> updates) { updates.forEach(this::write); } @Override public Intent getIntent(Key key) { IntentData data = currentMap.get(key); if (data != null) { return data.intent(); } return null; } @Override public IntentData getIntentData(Key key) { IntentData current = currentMap.get(key); if (current == null) { return null; } return new IntentData(current); } @Override public void addPending(IntentData data) { checkNotNull(data); if (data.version() == null) { data.setVersion(new WallClockTimestamp()); } data.setOrigin(clusterService.getLocalNode().id()); pendingMap.put(data.key(), new IntentData(data)); } @Override public boolean isMaster(Key intentKey) { return partitionService.isMine(intentKey); } @Override public Iterable<Intent> getPending() { return pendingMap.values().stream().map(IntentData::intent).collect(Collectors.toList()); } @Override public Iterable<IntentData> getPendingData() { return pendingMap.values(); } @Override public Iterable<IntentData> getPendingData(boolean localOnly, long olderThan) { long now = System.currentTimeMillis(); final WallClockTimestamp time = new WallClockTimestamp(now - olderThan); return pendingMap.values().stream() .filter(data -> data.version().isOlderThan(time) && (!localOnly || isMaster(data.key()))) .collect(Collectors.toList()); } private void notifyDelegateIfNotNull(IntentEvent event) { if (event != null) { notifyDelegate(event); } } private final class InternalCurrentListener implements EventuallyConsistentMapListener<Key, IntentData> { @Override public void event(EventuallyConsistentMapEvent<Key, IntentData> event) { IntentData intentData = event.value(); if (event.type() == EventuallyConsistentMapEvent.Type.PUT) { // The current intents map has been updated. If we are master for // this intent's partition, notify the Manager that it should // emit notifications about updated tracked resources. if (delegate != null && isMaster(event.value().intent().key())) { delegate.onUpdate(new IntentData(intentData)); // copy for safety, likely unnecessary } notifyDelegateIfNotNull(IntentEvent.getEvent(intentData)); } } } private final class InternalPendingListener implements EventuallyConsistentMapListener<Key, IntentData> { @Override public void event(EventuallyConsistentMapEvent<Key, IntentData> event) { if (event.type() == EventuallyConsistentMapEvent.Type.PUT) { // The pending intents map has been updated. If we are master for // this intent's partition, notify the Manager that it should do // some work. if (isMaster(event.value().intent().key())) { if (delegate != null) { delegate.process(new IntentData(event.value())); } } notifyDelegateIfNotNull(IntentEvent.getEvent(event.value())); } } } }