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