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