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

   1 /*
   2  * Copyright (c) 2016 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.sharding;
  10
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.util.concurrent.Futures;
  13 import com.google.common.util.concurrent.ListenableFuture;
  14 import java.util.Collection;
  15 import javax.annotation.Nonnull;
  16 import org.opendaylight.controller.cluster.databroker.actors.dds.ClientLocalHistory;
  17 import org.opendaylight.controller.cluster.databroker.actors.dds.ClientTransaction;
  18 import org.opendaylight.controller.cluster.databroker.actors.dds.DataStoreClient;
  19 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  20 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteCursor;
  21 import org.opendaylight.mdsal.dom.spi.shard.DOMDataTreeShardWriteTransaction;
  22 import org.opendaylight.mdsal.dom.spi.store.DOMStoreThreePhaseCommitCohort;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25
  26 /**
  27  * Proxy {@link DOMDataTreeShardWriteTransaction} that creates a proxy cursor that translates all calls into
  28  * {@link ClientTransaction} calls.
  29  */
  30 class ShardProxyTransaction implements DOMDataTreeShardWriteTransaction {
  31
  32     private static final Logger LOG = LoggerFactory.getLogger(ShardProxyTransaction.class);
  33     private static final ListenableFuture<Void> NULL_FUTURE = Futures.immediateFuture(null);
  34     private static final ListenableFuture<Boolean> VALIDATE_FUTURE = Futures.immediateFuture(true);
  35
  36     private final DOMDataTreeIdentifier shardRoot;
  37     private final Collection<DOMDataTreeIdentifier> prefixes;
  38     private final DataStoreClient client;
  39     private final ClientLocalHistory history;
  40     private ClientTransaction currentTx;
  41     private DOMStoreThreePhaseCommitCohort cohort;
  42
  43
  44     ShardProxyTransaction(final DOMDataTreeIdentifier shardRoot, final Collection<DOMDataTreeIdentifier> prefixes,
  45                           final DataStoreClient client) {
  46         this.shardRoot = Preconditions.checkNotNull(shardRoot);
  47         this.prefixes = Preconditions.checkNotNull(prefixes);
  48         this.client = Preconditions.checkNotNull(client);
  49         history = client.createLocalHistory();
  50         currentTx = history.createTransaction();
  51     }
  52
  53     @Nonnull
  54     @Override
  55     public DOMDataTreeWriteCursor createCursor(@Nonnull final DOMDataTreeIdentifier prefix) {
  56         checkAvailable(prefix);
  57
  58         return currentTx.openCursor();
  59     }
  60
  61     private void checkAvailable(final DOMDataTreeIdentifier prefix) {
  62         for (final DOMDataTreeIdentifier p : prefixes) {
  63             if (p.contains(prefix)) {
  64                 return;
  65             }
  66         }
  67         throw new IllegalArgumentException("Prefix[" + prefix + "] not available for this transaction. "
  68                 + "Available prefixes: " + prefixes);
  69     }
  70
  71     @Override
  72     public void ready() {
  73         LOG.debug("Readying transaction for shard {}", shardRoot);
  74
  75         Preconditions.checkState(cohort == null, "Transaction was readied already");
  76         cohort = currentTx.ready();
  77         currentTx = null;
  78     }
  79
  80     @Override
  81     public void close() {
  82         if (cohort != null) {
  83             cohort.abort();
  84             cohort = null;
  85         }
  86         if (currentTx != null) {
  87             currentTx.abort();
  88             currentTx = null;
  89         }
  90     }
  91
  92     @Override
  93     public ListenableFuture<Void> submit() {
  94         LOG.debug("Submitting transaction for shard {}", shardRoot);
  95
  96         Preconditions.checkNotNull(cohort, "Transaction not readied yet");
  97         return NULL_FUTURE;
  98     }
  99
 100     @Override
 101     public ListenableFuture<Boolean> validate() {
 102         LOG.debug("Validating transaction for shard {}", shardRoot);
 103
 104         Preconditions.checkNotNull(cohort, "Transaction not readied yet");
 105         return VALIDATE_FUTURE;
 106     }
 107
 108     @Override
 109     public ListenableFuture<Void> prepare() {
 110         LOG.debug("Preparing transaction for shard {}", shardRoot);
 111
 112         Preconditions.checkNotNull(cohort, "Transaction not readied yet");
 113         return NULL_FUTURE;
 114     }
 115
 116     @Override
 117     public ListenableFuture<Void> commit() {
 118         LOG.debug("Committing transaction for shard {}", shardRoot);
 119
 120         Preconditions.checkNotNull(cohort, "Transaction not readied yet");
 121         return NULL_FUTURE;
 122     }
 123 }