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

   1 /*
   2  * Copyright (c) 2015 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 package org.opendaylight.controller.cluster.datastore;
   9
  10 import akka.actor.ActorSelection;
  11 import akka.dispatch.Futures;
  12 import akka.dispatch.OnComplete;
  13 import com.google.common.base.Preconditions;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import java.util.Optional;
  16 import java.util.SortedSet;
  17 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  18 import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
  19 import org.opendaylight.controller.cluster.datastore.messages.ReadyLocalTransaction;
  20 import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
  21 import org.opendaylight.mdsal.dom.spi.store.DOMStoreThreePhaseCommitCohort;
  22 import org.opendaylight.mdsal.dom.spi.store.SnapshotBackedWriteTransaction;
  23 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
  24 import org.slf4j.Logger;
  25 import org.slf4j.LoggerFactory;
  26 import scala.concurrent.Future;
  27
  28 /**
  29  * Fake {@link DOMStoreThreePhaseCommitCohort} instantiated for local transactions to conform with the DOM
  30  * transaction APIs. It is only used to hold the data from a local DOM transaction ready operation and to
  31  * initiate direct or coordinated commits from the front-end by sending the ReadyLocalTransaction message.
  32  * It is not actually called by the front-end to perform 3PC thus the canCommit/preCommit/commit methods
  33  * are no-ops.
  34  */
  35 class LocalThreePhaseCommitCohort implements DOMStoreThreePhaseCommitCohort {
  36     private static final Logger LOG = LoggerFactory.getLogger(LocalThreePhaseCommitCohort.class);
  37
  38     private final SnapshotBackedWriteTransaction<TransactionIdentifier> transaction;
  39     private final DataTreeModification modification;
  40     private final ActorContext actorContext;
  41     private final ActorSelection leader;
  42     private final Exception operationError;
  43
  44     protected LocalThreePhaseCommitCohort(final ActorContext actorContext, final ActorSelection leader,
  45             final SnapshotBackedWriteTransaction<TransactionIdentifier> transaction,
  46             final DataTreeModification modification,
  47             final Exception operationError) {
  48         this.actorContext = Preconditions.checkNotNull(actorContext);
  49         this.leader = Preconditions.checkNotNull(leader);
  50         this.transaction = Preconditions.checkNotNull(transaction);
  51         this.modification = Preconditions.checkNotNull(modification);
  52         this.operationError = operationError;
  53     }
  54
  55     protected LocalThreePhaseCommitCohort(final ActorContext actorContext, final ActorSelection leader,
  56             final SnapshotBackedWriteTransaction<TransactionIdentifier> transaction, final Exception operationError) {
  57         this.actorContext = Preconditions.checkNotNull(actorContext);
  58         this.leader = Preconditions.checkNotNull(leader);
  59         this.transaction = Preconditions.checkNotNull(transaction);
  60         this.operationError = Preconditions.checkNotNull(operationError);
  61         this.modification = null;
  62     }
  63
  64     private Future<Object> initiateCommit(final boolean immediate,
  65             final Optional<SortedSet<String>> participatingShardNames) {
  66         if (operationError != null) {
  67             return Futures.failed(operationError);
  68         }
  69
  70         final ReadyLocalTransaction message = new ReadyLocalTransaction(transaction.getIdentifier(),
  71                 modification, immediate, participatingShardNames);
  72         return actorContext.executeOperationAsync(leader, message, actorContext.getTransactionCommitOperationTimeout());
  73     }
  74
  75     Future<ActorSelection> initiateCoordinatedCommit(Optional<SortedSet<String>> participatingShardNames) {
  76         final Future<Object> messageFuture = initiateCommit(false, participatingShardNames);
  77         final Future<ActorSelection> ret = TransactionReadyReplyMapper.transform(messageFuture, actorContext,
  78                 transaction.getIdentifier());
  79         ret.onComplete(new OnComplete<ActorSelection>() {
  80             @Override
  81             public void onComplete(final Throwable failure, final ActorSelection success) throws Throwable {
  82                 if (failure != null) {
  83                     LOG.info("Failed to prepare transaction {} on backend", transaction.getIdentifier(), failure);
  84                     transactionAborted(transaction);
  85                     return;
  86                 }
  87
  88                 LOG.debug("Transaction {} resolved to actor {}", transaction.getIdentifier(), success);
  89             }
  90         }, actorContext.getClientDispatcher());
  91
  92         return ret;
  93     }
  94
  95     Future<Object> initiateDirectCommit() {
  96         final Future<Object> messageFuture = initiateCommit(true, Optional.empty());
  97         messageFuture.onComplete(new OnComplete<Object>() {
  98             @Override
  99             public void onComplete(final Throwable failure, final Object message) throws Throwable {
 100                 if (failure != null) {
 101                     LOG.error("Failed to prepare transaction {} on backend", transaction.getIdentifier(), failure);
 102                     transactionAborted(transaction);
 103                 } else if (CommitTransactionReply.isSerializedType(message)) {
 104                     LOG.debug("Transaction {} committed successfully", transaction.getIdentifier());
 105                     transactionCommitted(transaction);
 106                 } else {
 107                     LOG.error("Transaction {} resulted in unhandled message type {}, aborting", message.getClass());
 108                     transactionAborted(transaction);
 109                 }
 110             }
 111         }, actorContext.getClientDispatcher());
 112
 113         return messageFuture;
 114     }
 115
 116     @Override
 117     public final ListenableFuture<Boolean> canCommit() {
 118         // Intended no-op
 119         throw new UnsupportedOperationException();
 120     }
 121
 122     @Override
 123     public final ListenableFuture<Void> preCommit() {
 124         // Intended no-op
 125         throw new UnsupportedOperationException();
 126     }
 127
 128     @Override
 129     public final ListenableFuture<Void> abort() {
 130         // Intended no-op
 131         throw new UnsupportedOperationException();
 132     }
 133
 134     @Override
 135     public final ListenableFuture<Void> commit() {
 136         // Intended no-op
 137         throw new UnsupportedOperationException();
 138     }
 139
 140     protected void transactionAborted(SnapshotBackedWriteTransaction<TransactionIdentifier> aborted) {
 141     }
 142
 143     protected void transactionCommitted(SnapshotBackedWriteTransaction<TransactionIdentifier> comitted) {
 144     }
 145 }