dom/mdsal-dom-inmemory-datastore/src/main/java/org/opendaylight/mdsal/dom/store/inmemory/InMemoryDOMStoreThreePhaseCommitCohort.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
   9 package org.opendaylight.mdsal.dom.store.inmemory;
  10
  11 import static com.google.common.base.Preconditions.checkState;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import com.google.common.annotations.VisibleForTesting;
  15 import com.google.common.util.concurrent.Futures;
  16 import com.google.common.util.concurrent.ListenableFuture;
  17 import org.opendaylight.mdsal.common.api.OptimisticLockFailedException;
  18 import org.opendaylight.mdsal.common.api.TransactionCommitFailedException;
  19 import org.opendaylight.mdsal.dom.spi.store.AbstractDOMStoreTransaction;
  20 import org.opendaylight.mdsal.dom.spi.store.DOMStoreThreePhaseCommitCohort;
  21 import org.opendaylight.mdsal.dom.spi.store.SnapshotBackedWriteTransaction;
  22 import org.opendaylight.yangtools.yang.data.tree.api.ConflictingModificationAppliedException;
  23 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidate;
  24 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeModification;
  25 import org.opendaylight.yangtools.yang.data.tree.api.DataValidationFailedException;
  26 import org.slf4j.Logger;
  27 import org.slf4j.LoggerFactory;
  28
  29 class InMemoryDOMStoreThreePhaseCommitCohort implements DOMStoreThreePhaseCommitCohort {
  30     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMStoreThreePhaseCommitCohort.class);
  31     private static final ListenableFuture<Void> SUCCESSFUL_FUTURE = Futures.immediateFuture(null);
  32     private static final ListenableFuture<Boolean> CAN_COMMIT_FUTURE = Futures.immediateFuture(Boolean.TRUE);
  33
  34     private final SnapshotBackedWriteTransaction<String> transaction;
  35     private final DataTreeModification modification;
  36     private final InMemoryDOMDataStore store;
  37     private final Exception operationError;
  38
  39     @VisibleForTesting
  40     DataTreeCandidate candidate;
  41
  42     InMemoryDOMStoreThreePhaseCommitCohort(final InMemoryDOMDataStore store,
  43             final SnapshotBackedWriteTransaction<String> transaction, final DataTreeModification modification,
  44             final Exception operationError) {
  45         this.transaction = requireNonNull(transaction);
  46         this.modification = requireNonNull(modification);
  47         this.store = requireNonNull(store);
  48         this.operationError = operationError;
  49     }
  50
  51     private static void warnDebugContext(final AbstractDOMStoreTransaction<?> transaction) {
  52         final Throwable ctx = transaction.getDebugContext();
  53         if (ctx != null) {
  54             LOG.warn("Transaction {} has been allocated in the following context", transaction.getIdentifier(), ctx);
  55         }
  56     }
  57
  58     @SuppressWarnings("checkstyle:IllegalCatch")
  59     @Override
  60     public final ListenableFuture<Boolean> canCommit() {
  61         if (operationError != null) {
  62             return Futures.immediateFailedFuture(operationError);
  63         }
  64
  65         try {
  66             store.validate(modification);
  67             LOG.debug("Store Transaction: {} can be committed", getTransaction().getIdentifier());
  68             return CAN_COMMIT_FUTURE;
  69         } catch (ConflictingModificationAppliedException e) {
  70             LOG.warn("Store Tx: {} Conflicting modification for {}.", getTransaction().getIdentifier(),
  71                     e.getPath());
  72             warnDebugContext(getTransaction());
  73             return Futures.immediateFailedFuture(new OptimisticLockFailedException("Optimistic lock failed.", e));
  74         } catch (DataValidationFailedException e) {
  75             LOG.warn("Store Tx: {} Data Precondition failed for {}.", getTransaction().getIdentifier(),
  76                     e.getPath(), e);
  77             warnDebugContext(getTransaction());
  78
  79             // For debugging purposes, allow dumping of the modification. Coupled with the above
  80             // precondition log, it should allow us to understand what went on.
  81             LOG.trace("Store Tx: {} modifications: {} tree: {}", getTransaction().getIdentifier(),
  82                     modification, store);
  83
  84             return Futures.immediateFailedFuture(
  85                     new TransactionCommitFailedException("Data did not pass validation.", e));
  86         } catch (Exception e) {
  87             LOG.warn("Unexpected failure in validation phase", e);
  88             return Futures.immediateFailedFuture(e);
  89         }
  90     }
  91
  92     @SuppressWarnings("checkstyle:IllegalCatch")
  93     @Override
  94     public final ListenableFuture<Void> preCommit() {
  95         try {
  96             candidate = store.prepare(modification);
  97             return SUCCESSFUL_FUTURE;
  98         } catch (Exception e) {
  99             LOG.warn("Unexpected failure in pre-commit phase", e);
 100             return Futures.immediateFailedFuture(e);
 101         }
 102     }
 103
 104     @Override
 105     public final ListenableFuture<Void> abort() {
 106         candidate = null;
 107         return SUCCESSFUL_FUTURE;
 108     }
 109
 110     protected final SnapshotBackedWriteTransaction<String> getTransaction() {
 111         return transaction;
 112     }
 113
 114     @Override
 115     public ListenableFuture<Void> commit() {
 116         checkState(candidate != null, "Proposed subtree must be computed");
 117
 118         /*
 119          * The commit has to occur atomically with regard to listener
 120          * registrations.
 121          */
 122         store.commit(candidate);
 123         return SUCCESSFUL_FUTURE;
 124     }
 125 }
 126