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.Optional;
  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.SettableFuture;
  18 import java.util.ArrayList;
  19 import java.util.Collection;
  20 import java.util.List;
  21 import java.util.Map.Entry;
  22 import java.util.stream.Collectors;
  23 import javax.annotation.Nonnull;
  24 import org.opendaylight.controller.cluster.databroker.actors.dds.ClientTransaction;
  25 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  26 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteCursor;
  27 import org.opendaylight.mdsal.dom.spi.shard.DOMDataTreeShardWriteTransaction;
  28 import org.opendaylight.mdsal.dom.spi.shard.ForeignShardModificationContext;
  29 import org.opendaylight.mdsal.dom.spi.store.DOMStoreThreePhaseCommitCohort;
  30 import org.opendaylight.mdsal.dom.store.inmemory.ForeignShardThreePhaseCommitCohort;
  31 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  32 import org.slf4j.Logger;
  33 import org.slf4j.LoggerFactory;
  34
  35 /**
  36  * Proxy {@link DOMDataTreeShardWriteTransaction} that creates a proxy cursor that translates all calls into
  37  * {@link ClientTransaction} calls.
  38  */
  39 class ShardProxyTransaction implements DOMDataTreeShardWriteTransaction {
  40
  41     private static final Logger LOG = LoggerFactory.getLogger(ShardProxyTransaction.class);
  42
  43     private final DOMDataTreeIdentifier shardRoot;
  44     private final Collection<DOMDataTreeIdentifier> prefixes;
  45     private final DistributedShardModification modification;
  46     private ClientTransaction currentTx;
  47     private final List<DOMStoreThreePhaseCommitCohort> cohorts = new ArrayList<>();
  48
  49     private DOMDataTreeWriteCursor cursor = null;
  50
  51     ShardProxyTransaction(final DOMDataTreeIdentifier shardRoot,
  52                           final Collection<DOMDataTreeIdentifier> prefixes,
  53                           final DistributedShardModification modification) {
  54         this.shardRoot = Preconditions.checkNotNull(shardRoot);
  55         this.prefixes = Preconditions.checkNotNull(prefixes);
  56         this.modification = Preconditions.checkNotNull(modification);
  57     }
  58
  59     private DOMDataTreeWriteCursor getCursor() {
  60         if (cursor == null) {
  61             cursor = new DistributedShardModificationCursor(modification, this);
  62         }
  63         return cursor;
  64     }
  65
  66     @Nonnull
  67     @Override
  68     public DOMDataTreeWriteCursor createCursor(@Nonnull 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         Preconditions.checkState(!cohorts.isEmpty(), "Transaction not readied yet");
 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.transform(validate(), validateFunction);
 133         // transform prepare into commit and return as submit result
 134         return Futures.transform(prepareFuture, prepareFunction);
 135     }
 136
 137     @Override
 138     public ListenableFuture<Boolean> validate() {
 139         LOG.debug("Validating transaction for shard {}", shardRoot);
 140
 141         Preconditions.checkState(!cohorts.isEmpty(), "Transaction not readied yet");
 142         final List<ListenableFuture<Boolean>> futures =
 143                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::canCommit).collect(Collectors.toList());
 144         final SettableFuture<Boolean> ret = SettableFuture.create();
 145
 146         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Boolean>>() {
 147             @Override
 148             public void onSuccess(final List<Boolean> result) {
 149                 ret.set(true);
 150             }
 151
 152             @Override
 153             public void onFailure(final Throwable throwable) {
 154                 ret.setException(throwable);
 155             }
 156         });
 157
 158         return ret;
 159     }
 160
 161     @Override
 162     public ListenableFuture<Void> prepare() {
 163         LOG.debug("Preparing transaction for shard {}", shardRoot);
 164
 165         Preconditions.checkState(!cohorts.isEmpty(), "Transaction not readied yet");
 166         final List<ListenableFuture<Void>> futures =
 167                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::preCommit).collect(Collectors.toList());
 168         final SettableFuture<Void> ret = SettableFuture.create();
 169
 170         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Void>>() {
 171             @Override
 172             public void onSuccess(final List<Void> result) {
 173                 ret.set(null);
 174             }
 175
 176             @Override
 177             public void onFailure(final Throwable throwable) {
 178                 ret.setException(throwable);
 179             }
 180         });
 181
 182         return ret;
 183     }
 184
 185     @Override
 186     public ListenableFuture<Void> commit() {
 187         LOG.debug("Committing transaction for shard {}", shardRoot);
 188
 189         Preconditions.checkState(!cohorts.isEmpty(), "Transaction not readied yet");
 190         final List<ListenableFuture<Void>> futures =
 191                 cohorts.stream().map(DOMStoreThreePhaseCommitCohort::commit).collect(Collectors.toList());
 192         final SettableFuture<Void> ret = SettableFuture.create();
 193
 194         Futures.addCallback(Futures.allAsList(futures), new FutureCallback<List<Void>>() {
 195             @Override
 196             public void onSuccess(final List<Void> result) {
 197                 ret.set(null);
 198             }
 199
 200             @Override
 201             public void onFailure(final Throwable throwable) {
 202                 ret.setException(throwable);
 203             }
 204         });
 205
 206         return ret;
 207     }
 208 }