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