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 javax.annotation.Nonnull;
  16 import org.opendaylight.controller.cluster.datastore.identifiers.TransactionIdentifier;
  17 import org.opendaylight.controller.cluster.datastore.messages.CommitTransactionReply;
  18 import org.opendaylight.controller.cluster.datastore.messages.ReadyLocalTransaction;
  19 import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
  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 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     }
  50
  51     protected LocalThreePhaseCommitCohort(final ActorContext actorContext, final ActorSelection leader,
  52             final SnapshotBackedWriteTransaction<TransactionIdentifier> transaction, final Exception operationError) {
  53         this.actorContext = Preconditions.checkNotNull(actorContext);
  54         this.leader = Preconditions.checkNotNull(leader);
  55         this.transaction = Preconditions.checkNotNull(transaction);
  56         this.operationError = Preconditions.checkNotNull(operationError);
  57         this.modification = null;
  58     }
  59
  60     private Future<Object> initiateCommit(final boolean immediate) {
  61         if(operationError != null) {
  62             return Futures.failed(operationError);
  63         }
  64
  65         final ReadyLocalTransaction message = new ReadyLocalTransaction(transaction.getIdentifier().toString(),
  66                 modification, immediate);
  67         return actorContext.executeOperationAsync(leader, message, actorContext.getTransactionCommitOperationTimeout());
  68     }
  69
  70     void setOperationError(@Nonnull Exception operationError) {
  71         if (this.operationError != null) {
  72             LOG.info("Cohort {} already had operation error", this, this.operationError);
  73         }
  74
  75         this.operationError = Preconditions.checkNotNull(operationError);
  76     }
  77
  78     Future<ActorSelection> initiateCoordinatedCommit() {
  79         final Future<Object> messageFuture = initiateCommit(false);
  80         final Future<ActorSelection> ret = TransactionReadyReplyMapper.transform(messageFuture, actorContext,
  81                 transaction.getIdentifier());
  82         ret.onComplete(new OnComplete<ActorSelection>() {
  83             @Override
  84             public void onComplete(final Throwable failure, final ActorSelection success) throws Throwable {
  85                 if (failure != null) {
  86                     LOG.info("Failed to prepare transaction {} on backend", transaction.getIdentifier(), failure);
  87                     transactionAborted(transaction);
  88                     return;
  89                 }
  90
  91                 LOG.debug("Transaction {} resolved to actor {}", transaction.getIdentifier(), success);
  92             }
  93         }, actorContext.getClientDispatcher());
  94
  95         return ret;
  96     }
  97
  98     Future<Object> initiateDirectCommit() {
  99         final Future<Object> messageFuture = initiateCommit(true);
 100         messageFuture.onComplete(new OnComplete<Object>() {
 101             @Override
 102             public void onComplete(final Throwable failure, final Object message) throws Throwable {
 103                 if (failure != null) {
 104                     LOG.error("Failed to prepare transaction {} on backend", transaction.getIdentifier(), failure);
 105                     transactionAborted(transaction);
 106                 } else if (CommitTransactionReply.SERIALIZABLE_CLASS.isInstance(message)) {
 107                     LOG.debug("Transaction {} committed successfully", transaction.getIdentifier());
 108                     transactionCommitted(transaction);
 109                 } else {
 110                     LOG.error("Transaction {} resulted in unhandled message type {}, aborting", message.getClass());
 111                     transactionAborted(transaction);
 112                 }
 113             }
 114         }, actorContext.getClientDispatcher());
 115
 116         return messageFuture;
 117     }
 118
 119     @Override
 120     public final ListenableFuture<Boolean> canCommit() {
 121         // Intended no-op
 122         throw new UnsupportedOperationException();
 123     }
 124
 125     @Override
 126     public final ListenableFuture<Void> preCommit() {
 127         // Intended no-op
 128         throw new UnsupportedOperationException();
 129     }
 130
 131     @Override
 132     public final ListenableFuture<Void> abort() {
 133         // Intended no-op
 134         throw new UnsupportedOperationException();
 135     }
 136
 137     @Override
 138     public final ListenableFuture<Void> commit() {
 139         // Intended no-op
 140         throw new UnsupportedOperationException();
 141     }
 142
 143     protected void transactionAborted(SnapshotBackedWriteTransaction<TransactionIdentifier> transaction) {
 144     }
 145
 146     protected void transactionCommitted(SnapshotBackedWriteTransaction<TransactionIdentifier> transaction) {
 147     }
 148 }