/*
* Copyright (c) 2016 Cisco Systems, Inc. and others. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.controller.cluster.sharding;
import com.google.common.base.Preconditions;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.annotation.Nonnull;
import javax.annotation.concurrent.GuardedBy;
import org.opendaylight.controller.cluster.databroker.actors.dds.DataStoreClient;
import org.opendaylight.controller.cluster.datastore.AbstractDataStore;
import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeListener;
import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
import org.opendaylight.mdsal.dom.api.DOMDataTreeShard;
import org.opendaylight.mdsal.dom.spi.shard.ChildShardContext;
import org.opendaylight.mdsal.dom.spi.shard.DOMDataTreeShardProducer;
import org.opendaylight.mdsal.dom.spi.shard.ForeignShardModificationContext;
import org.opendaylight.mdsal.dom.spi.shard.ReadableWriteableDOMDataTreeShard;
import org.opendaylight.mdsal.dom.spi.shard.SubshardProducerSpecification;
import org.opendaylight.mdsal.dom.spi.shard.WriteableDOMDataTreeShard;
import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Proxy implementation of a shard that creates forwarding producers to the backend shard.
*/
class DistributedShardFrontend implements ReadableWriteableDOMDataTreeShard {
private static final Logger LOG = LoggerFactory.getLogger(DistributedShardFrontend.class);
private final DataStoreClient client;
private final DOMDataTreeIdentifier shardRoot;
@GuardedBy("this")
private final Map<DOMDataTreeIdentifier, ChildShardContext> childShards = new HashMap<>();
@GuardedBy("this")
private final List<ShardProxyProducer> producers = new ArrayList<>();
private final DistributedShardChangePublisher publisher;
DistributedShardFrontend(final AbstractDataStore distributedDataStore,
final DataStoreClient client,
final DOMDataTreeIdentifier shardRoot) {
this.client = Preconditions.checkNotNull(client);
this.shardRoot = Preconditions.checkNotNull(shardRoot);
publisher = new DistributedShardChangePublisher(client, Preconditions.checkNotNull(distributedDataStore),
shardRoot, childShards);
}
@Override
public synchronized DOMDataTreeShardProducer createProducer(final Collection<DOMDataTreeIdentifier> paths) {
for (final DOMDataTreeIdentifier prodPrefix : paths) {
Preconditions.checkArgument(shardRoot.contains(prodPrefix), "Prefix %s is not contained under shard root",
prodPrefix, paths);
}
final ShardProxyProducer ret =
new ShardProxyProducer(shardRoot, paths, client, createModificationFactory(paths));
producers.add(ret);
return ret;
}
@Override
public synchronized void onChildAttached(final DOMDataTreeIdentifier prefix, final DOMDataTreeShard child) {
LOG.debug("{} : Child shard attached at {}", shardRoot, prefix);
Preconditions.checkArgument(child != this, "Attempted to attach child %s onto self", this);
addChildShard(prefix, child);
updateProducers();
}
@Override
public synchronized void onChildDetached(final DOMDataTreeIdentifier prefix, final DOMDataTreeShard child) {
LOG.debug("{} : Child shard detached at {}", shardRoot, prefix);
childShards.remove(prefix);
updateProducers();
// TODO we should grab the dataTreeSnapshot that's in the shard and apply it to this shard
}
private void addChildShard(final DOMDataTreeIdentifier prefix, final DOMDataTreeShard child) {
Preconditions.checkArgument(child instanceof WriteableDOMDataTreeShard);
childShards.put(prefix, new ChildShardContext(prefix, (WriteableDOMDataTreeShard) child));
}
DistributedShardModificationFactory createModificationFactory(final Collection<DOMDataTreeIdentifier> prefixes) {
// TODO this could be abstract
final Map<DOMDataTreeIdentifier, SubshardProducerSpecification> affectedSubshards = new HashMap<>();
for (final DOMDataTreeIdentifier producerPrefix : prefixes) {
for (final ChildShardContext maybeAffected : childShards.values()) {
final DOMDataTreeIdentifier bindPath;
if (producerPrefix.contains(maybeAffected.getPrefix())) {
bindPath = maybeAffected.getPrefix();
} else if (maybeAffected.getPrefix().contains(producerPrefix)) {
// Bound path is inside subshard
bindPath = producerPrefix;
} else {
continue;
}
SubshardProducerSpecification spec = affectedSubshards.get(maybeAffected.getPrefix());
if (spec == null) {
spec = new SubshardProducerSpecification(maybeAffected);
affectedSubshards.put(maybeAffected.getPrefix(), spec);
}
spec.addPrefix(bindPath);
}
}
final DistributedShardModificationFactoryBuilder builder =
new DistributedShardModificationFactoryBuilder(shardRoot);
for (final SubshardProducerSpecification spec : affectedSubshards.values()) {
final ForeignShardModificationContext foreignContext =
new ForeignShardModificationContext(spec.getPrefix(), spec.createProducer());
builder.addSubshard(foreignContext);
builder.addSubshard(spec.getPrefix(), foreignContext);
}
return builder.build();
}
private void updateProducers() {
for (final ShardProxyProducer producer : producers) {
producer.setModificationFactory(createModificationFactory(producer.getPrefixes()));
}
}
@Nonnull
@Override
public <L extends DOMDataTreeChangeListener> ListenerRegistration<L> registerTreeChangeListener(
final YangInstanceIdentifier treeId, final L listener) {
return publisher.registerTreeChangeListener(treeId, listener);
}
}