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 com.google.common.base.Preconditions.checkArgument;
  11 import static com.google.common.base.Preconditions.checkState;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import com.google.common.util.concurrent.AsyncFunction;
  15 import com.google.common.util.concurrent.FutureCallback;
  16 import com.google.common.util.concurrent.Futures;
  17 import com.google.common.util.concurrent.ListenableFuture;
  18 import com.google.common.util.concurrent.MoreExecutors;
  19 import com.google.common.util.concurrent.SettableFuture;
  20 import java.util.ArrayList;
  21 import java.util.Collection;
  22 import java.util.List;
  23 import java.util.Map.Entry;
  24 import java.util.Optional;
  25 import java.util.stream.Collectors;
  26 import org.opendaylight.controller.cluster.databroker.actors.dds.ClientTransaction;
  27 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  28 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteCursor;
  29 import org.opendaylight.mdsal.dom.spi.shard.DOMDataTreeShardWriteTransaction;
  30 import org.opendaylight.mdsal.dom.spi.shard.ForeignShardModificationContext;
  31 import org.opendaylight.mdsal.dom.spi.shard.ForeignShardThreePhaseCommitCohort;
  32 import org.opendaylight.mdsal.dom.spi.store.DOMStoreThreePhaseCommitCohort;
  33 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 /**
  38  * Proxy {@link DOMDataTreeShardWriteTransaction} that creates a proxy cursor that translates all calls into
  39  * {@link ClientTransaction} calls.
  40  */
  41 class ShardProxyTransaction implements DOMDataTreeShardWriteTransaction {
  42
  43     private static final Logger LOG = LoggerFactory.getLogger(ShardProxyTransaction.class);
  44
  45     private final DOMDataTreeIdentifier shardRoot;
  46     private final Collection<DOMDataTreeIdentifier> prefixes;
  47     private final DistributedShardModification modification;
  48     private ClientTransaction currentTx;
  49     private final List<DOMStoreThreePhaseCommitCohort> cohorts = new ArrayList<>();
  50
  51     private DOMDataTreeWriteCursor cursor = null;
  52
  53     ShardProxyTransaction(final DOMDataTreeIdentifier shardRoot,
  54                           final Collection<DOMDataTreeIdentifier> prefixes,
  55                           final DistributedShardModification modification) {
  56         this.shardRoot = requireNonNull(shardRoot);
  57         this.prefixes = requireNonNull(prefixes);
  58         this.modification = requireNonNull(modification);
  59     }
  60
  61     private DOMDataTreeWriteCursor getCursor() {
  62         if (cursor == null) {
  63             cursor = new DistributedShardModificationCursor(modification, this);
  64         }
  65         return cursor;
  66     }
  67
  68     @Override
  69     public DOMDataTreeWriteCursor createCursor(final DOMDataTreeIdentifier prefix) {
  70         checkAvailable(prefix);
  71         final YangInstanceIdentifier relativePath = toRelative(prefix.getRootIdentifier());
  72         final DOMDataTreeWriteCursor ret = getCursor();
  73         ret.enter(relativePath.getPathArguments());
  74         return ret;
  75     }
  76
  77     void cursorClosed() {
  78         cursor = null;
  79         modification.cursorClosed();
  80     }
  81
  82     private void checkAvailable(final DOMDataTreeIdentifier prefix) {
  83         for (final DOMDataTreeIdentifier p : prefixes) {
  84             if (p.contains(prefix)) {
  85                 return;
  86             }
  87         }
  88         throw new IllegalArgumentException("Prefix[" + prefix + "] not available for this transaction. "
  89                 + "Available prefixes: " + prefixes);
  90     }
  91
  92     private YangInstanceIdentifier toRelative(final YangInstanceIdentifier path) {
  93         final Optional<YangInstanceIdentifier> relative =
  94                 path.relativeTo(modification.getPrefix().getRootIdentifier());
  95         checkArgument(relative.isPresent());
  96         return relative.get();
  97     }
  98
  99     @Override
 100     public void ready() {
 101         LOG.debug("Readying transaction for shard {}", shardRoot);
 102
 103         requireNonNull(modification, "Attempting to ready an empty transaction.");
 104
 105         cohorts.add(modification.seal());
 106         for (Entry<DOMDataTreeIdentifier, ForeignShardModificationContext> entry
 107                 : modification.getChildShards().entrySet()) {
 108             cohorts.add(new ForeignShardThreePhaseCommitCohort(entry.getKey(), entry.getValue()));
 109         }
 110     }
 111
 112     @Override
 113     public void close() {
 114         cohorts.forEach(DOMStoreThreePhaseCommitCohort::abort);
 115         cohorts.clear();
 116
 117         if (currentTx != null) {
 118             currentTx.abort();
 119             currentTx = null;
 120         }
 121     }
 122
 123     @Override
 124     public ListenableFuture<Void> submit() {
 125         LOG.debug("Submitting transaction for shard {}", shardRoot);
 126
 127         checkTransactionReadied();
 128
 129         final AsyncFunction<Boolean, Void> validateFunction = input -> prepare();
 130         final AsyncFunction<Void, Void> prepareFunction = input -> commit();
 131
 132         // transform validate into prepare
 133         final ListenableFuture<Void> prepareFuture = Futures.transformAsync(validate(), validateFunction,
 134             MoreExecutors.directExecutor());
 135         // transform prepare into commit and return as submit result
 136         return Futures.transformAsync(prepareFuture, prepareFunction, MoreExecutors.directExecutor());
 137     }
 138
 139     private void checkTransactionReadied() {
 140         checkState(!cohorts.isEmpty(), "Transaction not readied yet");
 141     }
 142
 143     @Override
 144     public ListenableFuture<Boolean> validate() {
 145         LOG.debug("Validating transaction for shard {}", shardRoot);
 146
 147         checkTransactionReadied();
 148         final List<ListenableFuture<Boolean>> futures =
 149                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::canCommit).collect(Collectors.toList());
 150         final SettableFuture<Boolean> ret = SettableFuture.create();
 151
 152         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Boolean>>() {
 153             @Override
 154             public void onSuccess(final List<Boolean> result) {
 155                 ret.set(true);
 156             }
 157
 158             @Override
 159             public void onFailure(final Throwable throwable) {
 160                 ret.setException(throwable);
 161             }
 162         }, MoreExecutors.directExecutor());
 163
 164         return ret;
 165     }
 166
 167     @Override
 168     public ListenableFuture<Void> prepare() {
 169         LOG.debug("Preparing transaction for shard {}", shardRoot);
 170
 171         checkTransactionReadied();
 172         final List<ListenableFuture<Void>> futures =
 173                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::preCommit).collect(Collectors.toList());
 174         final SettableFuture<Void> ret = SettableFuture.create();
 175
 176         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Void>>() {
 177             @Override
 178             public void onSuccess(final List<Void> result) {
 179                 ret.set(null);
 180             }
 181
 182             @Override
 183             public void onFailure(final Throwable throwable) {
 184                 ret.setException(throwable);
 185             }
 186         }, MoreExecutors.directExecutor());
 187
 188         return ret;
 189     }
 190
 191     @Override
 192     public ListenableFuture<Void> commit() {
 193         LOG.debug("Committing transaction for shard {}", shardRoot);
 194
 195         checkTransactionReadied();
 196         final List<ListenableFuture<Void>> futures =
 197                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::commit).collect(Collectors.toList());
 198         final SettableFuture<Void> ret = SettableFuture.create();
 199
 200         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Void>>() {
 201             @Override
 202             public void onSuccess(final List<Void> result) {
 203                 ret.set(null);
 204             }
 205
 206             @Override
 207             public void onFailure(final Throwable throwable) {
 208                 ret.setException(throwable);
 209             }
 210         }, MoreExecutors.directExecutor());
 211
 212         return ret;
 213     }
 214 }