opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/TransactionProxy.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.ActorPath;
  12 import akka.actor.ActorRef;
  13 import akka.actor.ActorSelection;
  14 import akka.actor.Props;
  15
  16 import com.google.common.base.Optional;
  17 import com.google.common.util.concurrent.CheckedFuture;
  18 import com.google.common.util.concurrent.Futures;
  19 import com.google.common.util.concurrent.ListeningExecutorService;
  20
  21 import org.opendaylight.controller.cluster.datastore.exceptions.TimeoutException;
  22 import org.opendaylight.controller.cluster.datastore.messages.CloseTransaction;
  23 import org.opendaylight.controller.cluster.datastore.messages.CreateTransaction;
  24 import org.opendaylight.controller.cluster.datastore.messages.CreateTransactionReply;
  25 import org.opendaylight.controller.cluster.datastore.messages.DeleteData;
  26 import org.opendaylight.controller.cluster.datastore.messages.MergeData;
  27 import org.opendaylight.controller.cluster.datastore.messages.ReadData;
  28 import org.opendaylight.controller.cluster.datastore.messages.ReadDataReply;
  29 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransaction;
  30 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
  31 import org.opendaylight.controller.cluster.datastore.messages.WriteData;
  32 import org.opendaylight.controller.cluster.datastore.shardstrategy.ShardStrategyFactory;
  33 import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
  34 import org.opendaylight.controller.md.sal.common.api.data.ReadFailedException;
  35 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
  36 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
  37 import org.opendaylight.yangtools.util.concurrent.MappingCheckedFuture;
  38 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  39 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  40 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  41 import org.slf4j.Logger;
  42 import org.slf4j.LoggerFactory;
  43
  44 import java.util.ArrayList;
  45 import java.util.HashMap;
  46 import java.util.List;
  47 import java.util.Map;
  48 import java.util.concurrent.Callable;
  49 import java.util.concurrent.atomic.AtomicLong;
  50
  51 /**
  52  * TransactionProxy acts as a proxy for one or more transactions that were created on a remote shard
  53  * <p>
  54  * Creating a transaction on the consumer side will create one instance of a transaction proxy. If during
  55  * the transaction reads and writes are done on data that belongs to different shards then a separate transaction will
  56  * be created on each of those shards by the TransactionProxy
  57  *</p>
  58  * <p>
  59  * The TransactionProxy does not make any guarantees about atomicity or order in which the transactions on the various
  60  * shards will be executed.
  61  * </p>
  62  */
  63 public class TransactionProxy implements DOMStoreReadWriteTransaction {
  64     public enum TransactionType {
  65         READ_ONLY,
  66         WRITE_ONLY,
  67         READ_WRITE
  68     }
  69
  70     private static final AtomicLong counter = new AtomicLong();
  71
  72     private static final Logger
  73         LOG = LoggerFactory.getLogger(TransactionProxy.class);
  74
  75
  76     private final TransactionType transactionType;
  77     private final ActorContext actorContext;
  78     private final Map<String, TransactionContext> remoteTransactionPaths = new HashMap<>();
  79     private final String identifier;
  80     private final ListeningExecutorService executor;
  81     private final SchemaContext schemaContext;
  82
  83     public TransactionProxy(
  84         ActorContext actorContext,
  85         TransactionType transactionType,
  86         ListeningExecutorService executor,
  87         SchemaContext schemaContext
  88     ) {
  89
  90         this.identifier = actorContext.getCurrentMemberName() + "-txn-" + counter.getAndIncrement();
  91         this.transactionType = transactionType;
  92         this.actorContext = actorContext;
  93         this.executor = executor;
  94         this.schemaContext = schemaContext;
  95
  96
  97     }
  98
  99     @Override
 100     public CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> read(
 101             final YangInstanceIdentifier path) {
 102
 103         createTransactionIfMissing(actorContext, path);
 104
 105         return transactionContext(path).readData(path);
 106     }
 107
 108     @Override
 109     public void write(YangInstanceIdentifier path, NormalizedNode<?, ?> data) {
 110
 111         createTransactionIfMissing(actorContext, path);
 112
 113         transactionContext(path).writeData(path, data);
 114     }
 115
 116     @Override
 117     public void merge(YangInstanceIdentifier path, NormalizedNode<?, ?> data) {
 118
 119         createTransactionIfMissing(actorContext, path);
 120
 121         transactionContext(path).mergeData(path, data);
 122     }
 123
 124     @Override
 125     public void delete(YangInstanceIdentifier path) {
 126
 127         createTransactionIfMissing(actorContext, path);
 128
 129         transactionContext(path).deleteData(path);
 130     }
 131
 132     @Override
 133     public DOMStoreThreePhaseCommitCohort ready() {
 134         List<ActorPath> cohortPaths = new ArrayList<>();
 135
 136         for(TransactionContext transactionContext : remoteTransactionPaths.values()) {
 137             Object result = transactionContext.readyTransaction();
 138
 139             if(result.getClass().equals(ReadyTransactionReply.SERIALIZABLE_CLASS)){
 140                 ReadyTransactionReply reply = ReadyTransactionReply.fromSerializable(actorContext.getActorSystem(),result);
 141                 String resolvedCohortPath = transactionContext
 142                     .getResolvedCohortPath(reply.getCohortPath().toString());
 143                 cohortPaths.add(actorContext.actorFor(resolvedCohortPath));
 144             }
 145         }
 146
 147         return new ThreePhaseCommitCohortProxy(actorContext, cohortPaths, identifier, executor);
 148     }
 149
 150     @Override
 151     public Object getIdentifier() {
 152         return this.identifier;
 153     }
 154
 155     @Override
 156     public void close() {
 157         for(TransactionContext transactionContext : remoteTransactionPaths.values()) {
 158             transactionContext.closeTransaction();
 159         }
 160     }
 161
 162     private TransactionContext transactionContext(YangInstanceIdentifier path){
 163         String shardName = shardNameFromIdentifier(path);
 164         return remoteTransactionPaths.get(shardName);
 165     }
 166
 167     private String shardNameFromIdentifier(YangInstanceIdentifier path){
 168         return ShardStrategyFactory.getStrategy(path).findShard(path);
 169     }
 170
 171     private void createTransactionIfMissing(ActorContext actorContext, YangInstanceIdentifier path) {
 172         String shardName = ShardStrategyFactory.getStrategy(path).findShard(path);
 173
 174         TransactionContext transactionContext =
 175             remoteTransactionPaths.get(shardName);
 176
 177         if(transactionContext != null){
 178             // A transaction already exists with that shard
 179             return;
 180         }
 181
 182         try {
 183             Object response = actorContext.executeShardOperation(shardName,
 184                 new CreateTransaction(identifier).toSerializable(),
 185                 ActorContext.ASK_DURATION);
 186             if (response.getClass()
 187                 .equals(CreateTransactionReply.SERIALIZABLE_CLASS)) {
 188                 CreateTransactionReply reply =
 189                     CreateTransactionReply.fromSerializable(response);
 190
 191                 String transactionPath = reply.getTransactionPath();
 192
 193                 LOG.info("Received transaction path = {}"  , transactionPath );
 194
 195                 ActorSelection transactionActor =
 196                     actorContext.actorSelection(transactionPath);
 197                 transactionContext =
 198                     new TransactionContextImpl(shardName, transactionPath,
 199                         transactionActor);
 200
 201                 remoteTransactionPaths.put(shardName, transactionContext);
 202             }
 203         } catch(TimeoutException e){
 204             LOG.warn("Timed out trying to create transaction on shard {}: {}", shardName, e);
 205             remoteTransactionPaths.put(shardName, new NoOpTransactionContext(shardName));
 206         }
 207     }
 208
 209     private interface TransactionContext {
 210         String getShardName();
 211
 212         String getResolvedCohortPath(String cohortPath);
 213
 214         public void closeTransaction();
 215
 216         public Object readyTransaction();
 217
 218         void deleteData(YangInstanceIdentifier path);
 219
 220         void mergeData(YangInstanceIdentifier path, NormalizedNode<?, ?> data);
 221
 222         CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> readData(
 223                 final YangInstanceIdentifier path);
 224
 225         void writeData(YangInstanceIdentifier path, NormalizedNode<?, ?> data);
 226     }
 227
 228
 229     private class TransactionContextImpl implements TransactionContext{
 230         private final String shardName;
 231         private final String actorPath;
 232         private final ActorSelection  actor;
 233
 234
 235         private TransactionContextImpl(String shardName, String actorPath,
 236             ActorSelection actor) {
 237             this.shardName = shardName;
 238             this.actorPath = actorPath;
 239             this.actor = actor;
 240         }
 241
 242         @Override public String getShardName() {
 243             return shardName;
 244         }
 245
 246         private ActorSelection getActor() {
 247             return actor;
 248         }
 249
 250         @Override public String getResolvedCohortPath(String cohortPath){
 251             return actorContext.resolvePath(actorPath, cohortPath);
 252         }
 253
 254         @Override public void closeTransaction() {
 255             getActor().tell(
 256                 new CloseTransaction().toSerializable(), null);
 257         }
 258
 259         @Override public Object readyTransaction() {
 260             return actorContext.executeRemoteOperation(getActor(),
 261                 new ReadyTransaction().toSerializable(),
 262                 ActorContext.ASK_DURATION
 263             );
 264
 265         }
 266
 267         @Override public void deleteData(YangInstanceIdentifier path) {
 268             getActor().tell(new DeleteData(path).toSerializable(), null);
 269         }
 270
 271         @Override public void mergeData(YangInstanceIdentifier path, NormalizedNode<?, ?> data){
 272             getActor().tell(new MergeData(path, data, schemaContext).toSerializable(), null);
 273         }
 274
 275         @Override public CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> readData(
 276                 final YangInstanceIdentifier path) {
 277
 278             Callable<Optional<NormalizedNode<?,?>>> call = new Callable<Optional<NormalizedNode<?,?>>>() {
 279
 280                 @Override public Optional<NormalizedNode<?,?>> call() throws Exception {
 281                     Object response = actorContext
 282                         .executeRemoteOperation(getActor(), new ReadData(path).toSerializable(),
 283                             ActorContext.ASK_DURATION);
 284                     if(response.getClass().equals(ReadDataReply.SERIALIZABLE_CLASS)){
 285                         ReadDataReply reply = ReadDataReply.fromSerializable(schemaContext,path, response);
 286                         if(reply.getNormalizedNode() == null){
 287                             return Optional.absent();
 288                         }
 289                         return Optional.<NormalizedNode<?,?>>of(reply.getNormalizedNode());
 290                     }
 291
 292                     return Optional.absent();
 293                 }
 294             };
 295
 296             return MappingCheckedFuture.create(executor.submit(call), ReadFailedException.MAPPER);
 297         }
 298
 299         @Override public void writeData(YangInstanceIdentifier path, NormalizedNode<?, ?> data) {
 300             getActor().tell(new WriteData(path, data, schemaContext).toSerializable(), null);
 301         }
 302
 303     }
 304
 305     private class NoOpTransactionContext implements TransactionContext {
 306
 307         private final Logger
 308             LOG = LoggerFactory.getLogger(NoOpTransactionContext.class);
 309
 310         private final String shardName;
 311
 312         private ActorRef cohort;
 313
 314         public NoOpTransactionContext(String shardName){
 315             this.shardName = shardName;
 316         }
 317         @Override public String getShardName() {
 318             return  shardName;
 319
 320         }
 321
 322         @Override public String getResolvedCohortPath(String cohortPath) {
 323             return cohort.path().toString();
 324         }
 325
 326         @Override public void closeTransaction() {
 327             LOG.error("closeTransaction called");
 328         }
 329
 330         @Override public Object readyTransaction() {
 331             LOG.error("readyTransaction called");
 332             cohort = actorContext.getActorSystem().actorOf(Props.create(NoOpCohort.class));
 333             return new ReadyTransactionReply(cohort.path()).toSerializable();
 334         }
 335
 336         @Override public void deleteData(YangInstanceIdentifier path) {
 337             LOG.error("deleteData called path = {}", path);
 338         }
 339
 340         @Override public void mergeData(YangInstanceIdentifier path,
 341             NormalizedNode<?, ?> data) {
 342             LOG.error("mergeData called path = {}", path);
 343         }
 344
 345         @Override
 346         public CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> readData(
 347             YangInstanceIdentifier path) {
 348             LOG.error("readData called path = {}", path);
 349             return Futures.immediateCheckedFuture(
 350                 Optional.<NormalizedNode<?, ?>>absent());
 351         }
 352
 353         @Override public void writeData(YangInstanceIdentifier path,
 354             NormalizedNode<?, ?> data) {
 355             LOG.error("writeData called path = {}", path);
 356         }
 357     }
 358
 359
 360
 361 }