dom/mdsal-dom-broker/src/main/java/org/opendaylight/mdsal/dom/broker/ShardedDOMDataTreeProducer.java

   1 /*
   2  * Copyright (c) 2015 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.mdsal.dom.broker;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.collect.BiMap;
  12 import com.google.common.collect.ImmutableBiMap;
  13 import com.google.common.collect.ImmutableBiMap.Builder;
  14 import com.google.common.collect.ImmutableMap;
  15 import com.google.common.collect.ImmutableSet;
  16 import java.util.Collection;
  17 import java.util.Collections;
  18 import java.util.HashMap;
  19 import java.util.LinkedList;
  20 import java.util.Map;
  21 import java.util.Map.Entry;
  22 import java.util.Queue;
  23 import java.util.Set;
  24 import javax.annotation.concurrent.GuardedBy;
  25 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  26 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducer;
  27 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerBusyException;
  28 import org.opendaylight.mdsal.dom.api.DOMDataTreeProducerException;
  29 import org.opendaylight.mdsal.dom.api.DOMDataTreeShard;
  30 import org.opendaylight.mdsal.dom.api.DOMDataWriteTransaction;
  31 import org.opendaylight.mdsal.dom.spi.store.DOMStore;
  32 import org.opendaylight.mdsal.dom.spi.store.DOMStoreTransactionChain;
  33 import org.opendaylight.mdsal.dom.spi.store.DOMStoreWriteTransaction;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 final class ShardedDOMDataTreeProducer implements DOMDataTreeProducer {
  38     private static final Logger LOG = LoggerFactory.getLogger(ShardedDOMDataTreeProducer.class);
  39     private final BiMap<DOMDataTreeShard, DOMStoreTransactionChain> shardToChain;
  40     private final Map<DOMDataTreeIdentifier, DOMDataTreeShard> idToShard;
  41     private final ShardedDOMDataTree dataTree;
  42
  43     @GuardedBy("this")
  44     private Map<DOMDataTreeIdentifier, DOMDataTreeProducer> children = Collections.emptyMap();
  45     @GuardedBy("this")
  46     private DOMDataWriteTransaction openTx;
  47     @GuardedBy("this")
  48     private boolean closed;
  49
  50     @GuardedBy("this")
  51     private ShardedDOMDataTreeListenerContext<?> attachedListener;
  52
  53     ShardedDOMDataTreeProducer(final ShardedDOMDataTree dataTree, final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap, final Set<DOMDataTreeShard> shards) {
  54         this.dataTree = Preconditions.checkNotNull(dataTree);
  55
  56         // Create shard -> chain map
  57         final Builder<DOMDataTreeShard, DOMStoreTransactionChain> cb = ImmutableBiMap.builder();
  58         final Queue<Exception> es = new LinkedList<>();
  59
  60         for (final DOMDataTreeShard s : shards) {
  61             if (s instanceof DOMStore) {
  62                 try {
  63                     final DOMStoreTransactionChain c = ((DOMStore)s).createTransactionChain();
  64                     LOG.trace("Using DOMStore chain {} to access shard {}", c, s);
  65                     cb.put(s, c);
  66                 } catch (final Exception e) {
  67                     LOG.error("Failed to instantiate chain for shard {}", s, e);
  68                     es.add(e);
  69                 }
  70             } else {
  71                 LOG.error("Unhandled shard instance type {}", s.getClass());
  72             }
  73         }
  74         this.shardToChain = cb.build();
  75
  76         // An error was encountered, close chains and report the error
  77         if (shardToChain.size() != shards.size()) {
  78             for (final DOMStoreTransactionChain c : shardToChain.values()) {
  79                 try {
  80                     c.close();
  81                 } catch (final Exception e) {
  82                     LOG.warn("Exception raised while closing chain {}", c, e);
  83                 }
  84             }
  85
  86             final IllegalStateException e = new IllegalStateException("Failed to completely allocate contexts", es.poll());
  87             while (!es.isEmpty()) {
  88                 e.addSuppressed(es.poll());
  89             }
  90
  91             throw e;
  92         }
  93
  94         idToShard = ImmutableMap.copyOf(shardMap);
  95     }
  96
  97     @Override
  98     public synchronized DOMDataWriteTransaction createTransaction(final boolean isolated) {
  99         Preconditions.checkState(!closed, "Producer is already closed");
 100         Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
 101
 102         // Allocate backing transactions
 103         final Map<DOMDataTreeShard, DOMStoreWriteTransaction> shardToTx = new HashMap<>();
 104         for (final Entry<DOMDataTreeShard, DOMStoreTransactionChain> e : shardToChain.entrySet()) {
 105             shardToTx.put(e.getKey(), e.getValue().newWriteOnlyTransaction());
 106         }
 107
 108         // Create the ID->transaction map
 109         final ImmutableMap.Builder<DOMDataTreeIdentifier, DOMStoreWriteTransaction> b = ImmutableMap.builder();
 110         for (final Entry<DOMDataTreeIdentifier, DOMDataTreeShard> e : idToShard.entrySet()) {
 111             b.put(e.getKey(), shardToTx.get(e.getValue()));
 112         }
 113
 114         final ShardedDOMDataWriteTransaction ret = new ShardedDOMDataWriteTransaction(this, b.build());
 115         openTx = ret;
 116         return ret;
 117     }
 118
 119     @GuardedBy("this")
 120     private boolean haveSubtree(final DOMDataTreeIdentifier subtree) {
 121         for (final DOMDataTreeIdentifier i : idToShard.keySet()) {
 122             if (i.contains(subtree)) {
 123                 return true;
 124             }
 125         }
 126
 127         return false;
 128     }
 129
 130     @GuardedBy("this")
 131     private DOMDataTreeProducer lookupChild(final DOMDataTreeIdentifier s) {
 132         for (final Entry<DOMDataTreeIdentifier, DOMDataTreeProducer> e : children.entrySet()) {
 133             if (e.getKey().contains(s)) {
 134                 return e.getValue();
 135             }
 136         }
 137
 138         return null;
 139     }
 140
 141     @Override
 142     public synchronized DOMDataTreeProducer createProducer(final Collection<DOMDataTreeIdentifier> subtrees) {
 143         Preconditions.checkState(!closed, "Producer is already closed");
 144         Preconditions.checkState(openTx == null, "Transaction %s is still open", openTx);
 145
 146         for (final DOMDataTreeIdentifier s : subtrees) {
 147             // Check if the subtree was visible at any time
 148             Preconditions.checkArgument(haveSubtree(s), "Subtree %s was never available in producer %s", s, this);
 149             // Check if the subtree has not been delegated to a child
 150             final DOMDataTreeProducer child = lookupChild(s);
 151             Preconditions.checkArgument(child == null, "Subtree %s is delegated to child producer %s", s, child);
 152
 153             // Check if part of the requested subtree is not delegated to a child.
 154             for (final DOMDataTreeIdentifier c : children.keySet()) {
 155                 if (s.contains(c)) {
 156                     throw new IllegalArgumentException(String.format("Subtree %s cannot be delegated as it is superset of already-delegated %s", s, c));
 157                 }
 158             }
 159         }
 160
 161         final DOMDataTreeProducer ret = dataTree.createProducer(this, subtrees);
 162         final ImmutableMap.Builder<DOMDataTreeIdentifier, DOMDataTreeProducer> cb = ImmutableMap.builder();
 163         cb.putAll(children);
 164         for (final DOMDataTreeIdentifier s : subtrees) {
 165             cb.put(s, ret);
 166         }
 167
 168         children = cb.build();
 169         return ret;
 170     }
 171
 172     boolean isDelegatedToChild(DOMDataTreeIdentifier path) {
 173         for (final DOMDataTreeIdentifier c : children.keySet()) {
 174             if (c.contains(path)) {
 175                 return true;
 176             }
 177         }
 178         return false;
 179     }
 180
 181
 182     @Override
 183     public synchronized void close() throws DOMDataTreeProducerException {
 184         if (!closed) {
 185             if (openTx != null) {
 186                 throw new DOMDataTreeProducerBusyException(String.format("Transaction %s is still open", openTx));
 187             }
 188
 189             closed = true;
 190             dataTree.destroyProducer(this);
 191         }
 192     }
 193
 194     static DOMDataTreeProducer create(final ShardedDOMDataTree dataTree, final Map<DOMDataTreeIdentifier, DOMDataTreeShard> shardMap) {
 195         /*
 196          * FIXME: we do not allow multiple multiple shards in a producer because we do not implement the
 197          *        synchronization primitives yet
 198          */
 199         final Set<DOMDataTreeShard> shards = ImmutableSet.copyOf(shardMap.values());
 200         if (shards.size() > 1) {
 201             throw new UnsupportedOperationException("Cross-shard producers are not supported yet");
 202         }
 203
 204         return new ShardedDOMDataTreeProducer(dataTree, shardMap, shards);
 205     }
 206
 207     Set<DOMDataTreeIdentifier> getSubtrees() {
 208         return idToShard.keySet();
 209     }
 210
 211     synchronized void cancelTransaction(final ShardedDOMDataWriteTransaction transaction) {
 212         if (!openTx.equals(transaction)) {
 213             LOG.warn("Transaction {} is not open in producer {}", transaction, this);
 214             return;
 215         }
 216
 217         LOG.debug("Transaction {} cancelled", transaction);
 218         openTx = null;
 219     }
 220
 221     synchronized void transactionSubmitted(ShardedDOMDataWriteTransaction transaction) {
 222         Preconditions.checkState(openTx.equals(transaction));
 223         openTx = null;
 224     }
 225
 226     synchronized void boundToListener(ShardedDOMDataTreeListenerContext<?> listener) {
 227         // FIXME: Add option to dettach
 228         Preconditions.checkState(this.attachedListener == null,
 229                 "Producer %s is already attached to other listener.",
 230                 listener.getListener());
 231         this.attachedListener = listener;
 232     }
 233 }