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 package org.opendaylight.controller.cluster.sharding;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.util.concurrent.AsyncFunction;
  14 import com.google.common.util.concurrent.FutureCallback;
  15 import com.google.common.util.concurrent.Futures;
  16 import com.google.common.util.concurrent.ListenableFuture;
  17 import com.google.common.util.concurrent.MoreExecutors;
  18 import com.google.common.util.concurrent.SettableFuture;
  19 import java.util.ArrayList;
  20 import java.util.Collection;
  21 import java.util.List;
  22 import java.util.Map.Entry;
  23 import java.util.Optional;
  24 import java.util.stream.Collectors;
  25 import org.opendaylight.controller.cluster.databroker.actors.dds.ClientTransaction;
  26 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  27 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteCursor;
  28 import org.opendaylight.mdsal.dom.spi.shard.DOMDataTreeShardWriteTransaction;
  29 import org.opendaylight.mdsal.dom.spi.shard.ForeignShardModificationContext;
  30 import org.opendaylight.mdsal.dom.spi.store.DOMStoreThreePhaseCommitCohort;
  31 import org.opendaylight.mdsal.dom.store.inmemory.ForeignShardThreePhaseCommitCohort;
  32 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  33 import org.slf4j.Logger;
  34 import org.slf4j.LoggerFactory;
  35
  36 /**
  37  * Proxy {@link DOMDataTreeShardWriteTransaction} that creates a proxy cursor that translates all calls into
  38  * {@link ClientTransaction} calls.
  39  */
  40 class ShardProxyTransaction implements DOMDataTreeShardWriteTransaction {
  41
  42     private static final Logger LOG = LoggerFactory.getLogger(ShardProxyTransaction.class);
  43
  44     private final DOMDataTreeIdentifier shardRoot;
  45     private final Collection<DOMDataTreeIdentifier> prefixes;
  46     private final DistributedShardModification modification;
  47     private ClientTransaction currentTx;
  48     private final List<DOMStoreThreePhaseCommitCohort> cohorts = new ArrayList<>();
  49
  50     private DOMDataTreeWriteCursor cursor = null;
  51
  52     ShardProxyTransaction(final DOMDataTreeIdentifier shardRoot,
  53                           final Collection<DOMDataTreeIdentifier> prefixes,
  54                           final DistributedShardModification modification) {
  55         this.shardRoot = requireNonNull(shardRoot);
  56         this.prefixes = requireNonNull(prefixes);
  57         this.modification = requireNonNull(modification);
  58     }
  59
  60     private DOMDataTreeWriteCursor getCursor() {
  61         if (cursor == null) {
  62             cursor = new DistributedShardModificationCursor(modification, this);
  63         }
  64         return cursor;
  65     }
  66
  67     @Override
  68     public DOMDataTreeWriteCursor createCursor(final DOMDataTreeIdentifier prefix) {
  69         checkAvailable(prefix);
  70         final YangInstanceIdentifier relativePath = toRelative(prefix.getRootIdentifier());
  71         final DOMDataTreeWriteCursor ret = getCursor();
  72         ret.enter(relativePath.getPathArguments());
  73         return ret;
  74     }
  75
  76     void cursorClosed() {
  77         cursor = null;
  78         modification.cursorClosed();
  79     }
  80
  81     private void checkAvailable(final DOMDataTreeIdentifier prefix) {
  82         for (final DOMDataTreeIdentifier p : prefixes) {
  83             if (p.contains(prefix)) {
  84                 return;
  85             }
  86         }
  87         throw new IllegalArgumentException("Prefix[" + prefix + "] not available for this transaction. "
  88                 + "Available prefixes: " + prefixes);
  89     }
  90
  91     private YangInstanceIdentifier toRelative(final YangInstanceIdentifier path) {
  92         final Optional<YangInstanceIdentifier> relative =
  93                 path.relativeTo(modification.getPrefix().getRootIdentifier());
  94         Preconditions.checkArgument(relative.isPresent());
  95         return relative.get();
  96     }
  97
  98     @Override
  99     public void ready() {
 100         LOG.debug("Readying transaction for shard {}", shardRoot);
 101
 102         Preconditions.checkNotNull(modification, "Attempting to ready an empty transaction.");
 103
 104         cohorts.add(modification.seal());
 105         for (Entry<DOMDataTreeIdentifier, ForeignShardModificationContext> entry
 106                 : modification.getChildShards().entrySet()) {
 107             cohorts.add(new ForeignShardThreePhaseCommitCohort(entry.getKey(), entry.getValue()));
 108         }
 109     }
 110
 111     @Override
 112     public void close() {
 113         cohorts.forEach(DOMStoreThreePhaseCommitCohort::abort);
 114         cohorts.clear();
 115
 116         if (currentTx != null) {
 117             currentTx.abort();
 118             currentTx = null;
 119         }
 120     }
 121
 122     @Override
 123     public ListenableFuture<Void> submit() {
 124         LOG.debug("Submitting transaction for shard {}", shardRoot);
 125
 126         checkTransactionReadied();
 127
 128         final AsyncFunction<Boolean, Void> validateFunction = input -> prepare();
 129         final AsyncFunction<Void, Void> prepareFunction = input -> commit();
 130
 131         // transform validate into prepare
 132         final ListenableFuture<Void> prepareFuture = Futures.transformAsync(validate(), validateFunction,
 133             MoreExecutors.directExecutor());
 134         // transform prepare into commit and return as submit result
 135         return Futures.transformAsync(prepareFuture, prepareFunction, MoreExecutors.directExecutor());
 136     }
 137
 138     private void checkTransactionReadied() {
 139         Preconditions.checkState(!cohorts.isEmpty(), "Transaction not readied yet");
 140     }
 141
 142     @Override
 143     public ListenableFuture<Boolean> validate() {
 144         LOG.debug("Validating transaction for shard {}", shardRoot);
 145
 146         checkTransactionReadied();
 147         final List<ListenableFuture<Boolean>> futures =
 148                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::canCommit).collect(Collectors.toList());
 149         final SettableFuture<Boolean> ret = SettableFuture.create();
 150
 151         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Boolean>>() {
 152             @Override
 153             public void onSuccess(final List<Boolean> result) {
 154                 ret.set(true);
 155             }
 156
 157             @Override
 158             public void onFailure(final Throwable throwable) {
 159                 ret.setException(throwable);
 160             }
 161         }, MoreExecutors.directExecutor());
 162
 163         return ret;
 164     }
 165
 166     @Override
 167     public ListenableFuture<Void> prepare() {
 168         LOG.debug("Preparing transaction for shard {}", shardRoot);
 169
 170         checkTransactionReadied();
 171         final List<ListenableFuture<Void>> futures =
 172                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::preCommit).collect(Collectors.toList());
 173         final SettableFuture<Void> ret = SettableFuture.create();
 174
 175         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Void>>() {
 176             @Override
 177             public void onSuccess(final List<Void> result) {
 178                 ret.set(null);
 179             }
 180
 181             @Override
 182             public void onFailure(final Throwable throwable) {
 183                 ret.setException(throwable);
 184             }
 185         }, MoreExecutors.directExecutor());
 186
 187         return ret;
 188     }
 189
 190     @Override
 191     public ListenableFuture<Void> commit() {
 192         LOG.debug("Committing transaction for shard {}", shardRoot);
 193
 194         checkTransactionReadied();
 195         final List<ListenableFuture<Void>> futures =
 196                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::commit).collect(Collectors.toList());
 197         final SettableFuture<Void> ret = SettableFuture.create();
 198
 199         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Void>>() {
 200             @Override
 201             public void onSuccess(final List<Void> result) {
 202                 ret.set(null);
 203             }
 204
 205             @Override
 206             public void onFailure(final Throwable throwable) {
 207                 ret.setException(throwable);
 208             }
 209         }, MoreExecutors.directExecutor());
 210
 211         return ret;
 212     }
 213 }