opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/Shard.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.cluster.datastore;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.ActorSelection;
  13 import akka.actor.Props;
  14 import akka.event.Logging;
  15 import akka.event.LoggingAdapter;
  16 import akka.japi.Creator;
  17 import akka.serialization.Serialization;
  18
  19 import com.google.common.util.concurrent.ListenableFuture;
  20 import com.google.common.util.concurrent.ListeningExecutorService;
  21 import com.google.common.util.concurrent.MoreExecutors;
  22
  23 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardMBeanFactory;
  24 import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardStats;
  25 import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
  26 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
  27 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionChain;
  28 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionChainReply;
  29 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply;
  30 import org.opendaylight.controller.cluster.datastore.messages.EnableNotification;
  31 import org.opendaylight.controller.cluster.datastore.messages.ForwardedCommitTransaction;
  32 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
  33 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListener;
  34 import org.opendaylight.controller.cluster.datastore.messages.RegisterChangeListenerReply;
  35 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  36 import org.opendaylight.controller.cluster.datastore.modification.Modification;
  37 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
  38 import org.opendaylight.controller.cluster.raft.RaftActor;
  39 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
  40 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStore;
  41 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  42 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  43 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
  44 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  45 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  46 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  47
  48 import java.util.ArrayList;
  49 import java.util.HashMap;
  50 import java.util.List;
  51 import java.util.Map;
  52 import java.util.concurrent.ExecutionException;
  53 import java.util.concurrent.Executors;
  54
  55 /**
  56  * A Shard represents a portion of the logical data tree <br/>
  57  * <p>
  58  * Our Shard uses InMemoryDataStore as it's internal representation and delegates all requests it
  59  * </p>
  60  */
  61 public class Shard extends RaftActor {
  62
  63     public static final String DEFAULT_NAME = "default";
  64
  65     private final ListeningExecutorService storeExecutor =
  66         MoreExecutors.listeningDecorator(Executors.newFixedThreadPool(2));
  67
  68     private final InMemoryDOMDataStore store;
  69
  70     private final Map<Object, DOMStoreThreePhaseCommitCohort>
  71         modificationToCohort = new HashMap<>();
  72
  73     private final LoggingAdapter LOG =
  74         Logging.getLogger(getContext().system(), this);
  75
  76     // By default persistent will be true and can be turned off using the system
  77     // property persistent
  78     private final boolean persistent;
  79
  80     private final String name;
  81
  82     private volatile SchemaContext schemaContext;
  83
  84     private final ShardStats shardMBean;
  85
  86     private final List<ActorSelection> dataChangeListeners = new ArrayList<>();
  87
  88     private Shard(String name, Map<String, String> peerAddresses) {
  89         super(name, peerAddresses);
  90
  91         this.name = name;
  92
  93         String setting = System.getProperty("shard.persistent");
  94
  95         this.persistent = !"false".equals(setting);
  96
  97         LOG.info("Creating shard : {} persistent : {}", name, persistent);
  98
  99         store = new InMemoryDOMDataStore(name, storeExecutor);
 100
 101         shardMBean = ShardMBeanFactory.getShardStatsMBean(name);
 102
 103     }
 104
 105     public static Props props(final String name, final Map<String, String> peerAddresses) {
 106         return Props.create(new Creator<Shard>() {
 107
 108             @Override
 109             public Shard create() throws Exception {
 110                 return new Shard(name, peerAddresses);
 111             }
 112
 113         });
 114     }
 115
 116
 117     @Override public void onReceiveCommand(Object message){
 118         LOG.debug("Received message {} from {}", message.getClass().toString(), getSender());
 119
 120         if (message.getClass().equals(CreateTransactionChain.SERIALIZABLE_CLASS)) {
 121             if(isLeader()) {
 122                 createTransactionChain();
 123             } else if(getLeader() != null){
 124                 getLeader().forward(message, getContext());
 125             }
 126         } else if (message.getClass().equals(RegisterChangeListener.SERIALIZABLE_CLASS)) {
 127             registerChangeListener(RegisterChangeListener.fromSerializable(getContext().system(), message));
 128         } else if (message instanceof UpdateSchemaContext) {
 129             updateSchemaContext((UpdateSchemaContext) message);
 130         } else if (message instanceof ForwardedCommitTransaction) {
 131             handleForwardedCommit((ForwardedCommitTransaction) message);
 132         } else if (message.getClass().equals(CreateTransaction.SERIALIZABLE_CLASS)) {
 133             if(isLeader()) {
 134                 createTransaction(CreateTransaction.fromSerializable(message));
 135             } else if(getLeader() != null){
 136                 getLeader().forward(message, getContext());
 137             }
 138         } else if (message instanceof PeerAddressResolved){
 139             PeerAddressResolved resolved = (PeerAddressResolved) message;
 140             setPeerAddress(resolved.getPeerId(), resolved.getPeerAddress());
 141         } else {
 142           super.onReceiveCommand(message);
 143         }
 144     }
 145
 146     private void createTransaction(CreateTransaction createTransaction) {
 147         DOMStoreReadWriteTransaction transaction =
 148             store.newReadWriteTransaction();
 149         String transactionId = "shard-" + createTransaction.getTransactionId();
 150         LOG.info("Creating transaction : {} " , transactionId);
 151         ActorRef transactionActor = getContext().actorOf(
 152             ShardTransaction.props(transaction, getSelf(), schemaContext), transactionId);
 153
 154         getSender()
 155             .tell(new CreateTransactionReply(Serialization.serializedActorPath(transactionActor), createTransaction.getTransactionId()).toSerializable(),
 156                 getSelf());
 157     }
 158
 159     private void commit(final ActorRef sender, Object serialized) {
 160         Modification modification = MutableCompositeModification.fromSerializable(serialized, schemaContext);
 161         DOMStoreThreePhaseCommitCohort cohort =
 162             modificationToCohort.remove(serialized);
 163         if (cohort == null) {
 164             LOG.error(
 165                 "Could not find cohort for modification : {}", modification);
 166             LOG.info("Writing modification using a new transaction");
 167             DOMStoreReadWriteTransaction transaction =
 168                 store.newReadWriteTransaction();
 169             modification.apply(transaction);
 170             DOMStoreThreePhaseCommitCohort commitCohort = transaction.ready();
 171             ListenableFuture<Void> future =
 172                 commitCohort.preCommit();
 173             try {
 174                 future.get();
 175                 future = commitCohort.commit();
 176                 future.get();
 177             } catch (InterruptedException e) {
 178                 LOG.error("Failed to commit", e);
 179             } catch (ExecutionException e) {
 180                 LOG.error("Failed to commit", e);
 181             }
 182         }
 183
 184         final ListenableFuture<Void> future = cohort.commit();
 185         shardMBean.incrementCommittedTransactionCount();
 186         final ActorRef self = getSelf();
 187         future.addListener(new Runnable() {
 188             @Override
 189             public void run() {
 190                 try {
 191                     future.get();
 192
 193                     if(sender != null) {
 194                         sender
 195                             .tell(new CommitTransactionReply().toSerializable(),
 196                                 self);
 197                     } else {
 198                         LOG.error("sender is null ???");
 199                     }
 200                 } catch (InterruptedException | ExecutionException e) {
 201                     // FIXME : Handle this properly
 202                     LOG.error(e, "An exception happened when committing");
 203                 }
 204             }
 205         }, getContext().dispatcher());
 206     }
 207
 208     private void handleForwardedCommit(ForwardedCommitTransaction message) {
 209         Object serializedModification = message.getModification().toSerializable();
 210
 211         modificationToCohort
 212             .put(serializedModification , message.getCohort());
 213
 214         if(persistent) {
 215             this.persistData(getSender(), "identifier", new CompositeModificationPayload(serializedModification));
 216         } else {
 217             this.commit(getSender(), serializedModification);
 218         }
 219     }
 220
 221     private void updateSchemaContext(UpdateSchemaContext message) {
 222         this.schemaContext = message.getSchemaContext();
 223         store.onGlobalContextUpdated(message.getSchemaContext());
 224     }
 225
 226     private void registerChangeListener(
 227         RegisterChangeListener registerChangeListener) {
 228
 229         LOG.debug("registerDataChangeListener for " + registerChangeListener.getPath());
 230
 231
 232         ActorSelection dataChangeListenerPath = getContext()
 233             .system().actorSelection(
 234                 registerChangeListener.getDataChangeListenerPath());
 235
 236
 237         // Notify the listener if notifications should be enabled or not
 238         // If this shard is the leader then it will enable notifications else
 239         // it will not
 240         dataChangeListenerPath.tell(new EnableNotification(isLeader()), getSelf());
 241
 242         // Now store a reference to the data change listener so it can be notified
 243         // at a later point if notifications should be enabled or disabled
 244         dataChangeListeners.add(dataChangeListenerPath);
 245
 246         AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>
 247             listener = new DataChangeListenerProxy(schemaContext,dataChangeListenerPath);
 248
 249         org.opendaylight.yangtools.concepts.ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>>
 250             registration =
 251             store.registerChangeListener(registerChangeListener.getPath(),
 252                 listener, registerChangeListener.getScope());
 253         ActorRef listenerRegistration =
 254             getContext().actorOf(
 255                 DataChangeListenerRegistration.props(registration));
 256
 257         LOG.debug("registerDataChangeListener sending reply, listenerRegistrationPath = " + listenerRegistration.path().toString());
 258
 259         getSender()
 260             .tell(new RegisterChangeListenerReply(listenerRegistration.path()).toSerializable(),
 261                 getSelf());
 262     }
 263
 264     private void createTransactionChain() {
 265         DOMStoreTransactionChain chain = store.createTransactionChain();
 266         ActorRef transactionChain =
 267             getContext().actorOf(
 268                 ShardTransactionChain.props(chain, schemaContext));
 269         getSender()
 270             .tell(new CreateTransactionChainReply(transactionChain.path())
 271                 .toSerializable(),
 272                 getSelf());
 273     }
 274
 275     @Override protected void applyState(ActorRef clientActor, String identifier,
 276         Object data) {
 277
 278         if(data instanceof CompositeModificationPayload){
 279             Object modification =
 280                 ((CompositeModificationPayload) data).getModification();
 281
 282             if(modification != null){
 283                 commit(clientActor, modification);
 284             } else {
 285                 LOG.error("modification is null - this is very unexpected");
 286             }
 287
 288
 289         } else {
 290             LOG.error("Unknown state received {}", data);
 291         }
 292
 293     }
 294
 295     @Override protected Object createSnapshot() {
 296         throw new UnsupportedOperationException("createSnapshot");
 297     }
 298
 299     @Override protected void applySnapshot(Object snapshot) {
 300         throw new UnsupportedOperationException("applySnapshot");
 301     }
 302
 303     @Override protected void onStateChanged() {
 304         for(ActorSelection dataChangeListener : dataChangeListeners){
 305             dataChangeListener.tell(new EnableNotification(isLeader()), getSelf());
 306         }
 307     }
 308
 309     @Override public String persistenceId() {
 310         return this.name;
 311     }
 312 }