opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/AbstractProxyTransaction.java

   1 /*
   2  * Copyright (c) 2016 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.controller.cluster.databroker.actors.dds;
   9
  10 import akka.actor.ActorRef;
  11 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.base.Verify;
  14 import com.google.common.util.concurrent.CheckedFuture;
  15 import com.google.common.util.concurrent.ListenableFuture;
  16 import com.google.common.util.concurrent.SettableFuture;
  17 import java.util.function.Consumer;
  18 import javax.annotation.Nullable;
  19 import org.opendaylight.controller.cluster.access.commands.TransactionAbortRequest;
  20 import org.opendaylight.controller.cluster.access.commands.TransactionAbortSuccess;
  21 import org.opendaylight.controller.cluster.access.commands.TransactionCanCommitSuccess;
  22 import org.opendaylight.controller.cluster.access.commands.TransactionCommitSuccess;
  23 import org.opendaylight.controller.cluster.access.commands.TransactionDoCommitRequest;
  24 import org.opendaylight.controller.cluster.access.commands.TransactionPreCommitRequest;
  25 import org.opendaylight.controller.cluster.access.commands.TransactionPreCommitSuccess;
  26 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
  27 import org.opendaylight.controller.cluster.access.concepts.RequestException;
  28 import org.opendaylight.controller.cluster.access.concepts.RequestFailure;
  29 import org.opendaylight.controller.cluster.access.concepts.Response;
  30 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
  31 import org.opendaylight.mdsal.common.api.ReadFailedException;
  32 import org.opendaylight.yangtools.concepts.Identifiable;
  33 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  34 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  35 import org.slf4j.Logger;
  36 import org.slf4j.LoggerFactory;
  37
  38 /**
  39  * Class translating transaction operations towards a particular backend shard.
  40  *
  41  * <p>
  42  * This class is not safe to access from multiple application threads, as is usual for transactions. Internal state
  43  * transitions coming from interactions with backend are expected to be thread-safe.
  44  *
  45  * <p>
  46  * This class interacts with the queueing mechanism in ClientActorBehavior, hence once we arrive at a decision
  47  * to use either a local or remote implementation, we are stuck with it. We can re-evaluate on the next transaction.
  48  *
  49  * @author Robert Varga
  50  */
  51 abstract class AbstractProxyTransaction implements Identifiable<TransactionIdentifier> {
  52     private static final Logger LOG = LoggerFactory.getLogger(AbstractProxyTransaction.class);
  53
  54     private final ProxyHistory parent;
  55
  56     private AbstractProxyTransaction successor;
  57     private long sequence;
  58     private boolean sealed;
  59
  60     AbstractProxyTransaction(final ProxyHistory parent) {
  61         this.parent = Preconditions.checkNotNull(parent);
  62     }
  63
  64     final ActorRef localActor() {
  65         return parent.localActor();
  66     }
  67
  68     final long nextSequence() {
  69         return sequence++;
  70     }
  71
  72     final void delete(final YangInstanceIdentifier path) {
  73         checkNotSealed();
  74         doDelete(path);
  75     }
  76
  77     final void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  78         checkNotSealed();
  79         doMerge(path, data);
  80     }
  81
  82     final void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
  83         checkNotSealed();
  84         doWrite(path, data);
  85     }
  86
  87     final CheckedFuture<Boolean, ReadFailedException> exists(final YangInstanceIdentifier path) {
  88         checkNotSealed();
  89         return doExists(path);
  90     }
  91
  92     final CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> read(final YangInstanceIdentifier path) {
  93         checkNotSealed();
  94         return doRead(path);
  95     }
  96
  97     final void sendRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
  98         LOG.debug("Transaction proxy {} sending request {} callback {}", this, request, callback);
  99         parent.sendRequest(request, callback);
 100     }
 101
 102     /**
 103      * Seal this transaction before it is either committed or aborted.
 104      */
 105     final void seal() {
 106         checkNotSealed();
 107         doSeal();
 108         sealed = true;
 109         parent.onTransactionSealed(this);
 110     }
 111
 112     private void checkNotSealed() {
 113         Preconditions.checkState(!sealed, "Transaction %s has already been sealed", getIdentifier());
 114     }
 115
 116     private void checkSealed() {
 117         Preconditions.checkState(sealed, "Transaction %s has not been sealed yet", getIdentifier());
 118     }
 119
 120     /**
 121      * Abort this transaction. This is invoked only for read-only transactions and will result in an explicit message
 122      * being sent to the backend.
 123      */
 124     final void abort() {
 125         checkNotSealed();
 126         doAbort();
 127         parent.abortTransaction(this);
 128     }
 129
 130     final void abort(final VotingFuture<Void> ret) {
 131         checkSealed();
 132
 133         sendAbort(t -> {
 134             if (t instanceof TransactionAbortSuccess) {
 135                 ret.voteYes();
 136             } else if (t instanceof RequestFailure) {
 137                 ret.voteNo(((RequestFailure<?, ?>) t).getCause());
 138             } else {
 139                 ret.voteNo(new IllegalStateException("Unhandled response " + t.getClass()));
 140             }
 141
 142             parent.completeTransaction(this);
 143         });
 144     }
 145
 146     final void sendAbort(final Consumer<Response<?, ?>> callback) {
 147         sendRequest(new TransactionAbortRequest(getIdentifier(), nextSequence(), localActor()), callback);
 148     }
 149
 150     /**
 151      * Commit this transaction, possibly in a coordinated fashion.
 152      *
 153      * @param coordinated True if this transaction should be coordinated across multiple participants.
 154      * @return Future completion
 155      */
 156     final ListenableFuture<Boolean> directCommit() {
 157         checkSealed();
 158
 159         final SettableFuture<Boolean> ret = SettableFuture.create();
 160         sendRequest(Verify.verifyNotNull(commitRequest(false)), t -> {
 161             if (t instanceof TransactionCommitSuccess) {
 162                 ret.set(Boolean.TRUE);
 163             } else if (t instanceof RequestFailure) {
 164                 ret.setException(((RequestFailure<?, ?>) t).getCause());
 165             } else {
 166                 ret.setException(new IllegalStateException("Unhandled response " + t.getClass()));
 167             }
 168
 169             parent.completeTransaction(this);
 170         });
 171         return ret;
 172     }
 173
 174
 175     void canCommit(final VotingFuture<?> ret) {
 176         checkSealed();
 177
 178         sendRequest(Verify.verifyNotNull(commitRequest(true)), t -> {
 179             if (t instanceof TransactionCanCommitSuccess) {
 180                 ret.voteYes();
 181             } else if (t instanceof RequestFailure) {
 182                 ret.voteNo(((RequestFailure<?, ?>) t).getCause());
 183             } else {
 184                 ret.voteNo(new IllegalStateException("Unhandled response " + t.getClass()));
 185             }
 186         });
 187     }
 188
 189     void preCommit(final VotingFuture<?> ret) {
 190         checkSealed();
 191
 192         sendRequest(new TransactionPreCommitRequest(getIdentifier(), nextSequence(), localActor()), t -> {
 193             if (t instanceof TransactionPreCommitSuccess) {
 194                 ret.voteYes();
 195             } else if (t instanceof RequestFailure) {
 196                 ret.voteNo(((RequestFailure<?, ?>) t).getCause());
 197             } else {
 198                 ret.voteNo(new IllegalStateException("Unhandled response " + t.getClass()));
 199             }
 200         });
 201     }
 202
 203     void doCommit(final VotingFuture<?> ret) {
 204         checkSealed();
 205
 206         sendRequest(new TransactionDoCommitRequest(getIdentifier(), nextSequence(), localActor()), t -> {
 207             if (t instanceof TransactionCommitSuccess) {
 208                 ret.voteYes();
 209             } else if (t instanceof RequestFailure) {
 210                 ret.voteNo(((RequestFailure<?, ?>) t).getCause());
 211             } else {
 212                 ret.voteNo(new IllegalStateException("Unhandled response " + t.getClass()));
 213             }
 214
 215             parent.completeTransaction(this);
 216         });
 217     }
 218
 219     void replaySuccessfulRequests(final AbstractProxyTransaction successor) {
 220         this.successor = Preconditions.checkNotNull(successor);
 221     }
 222
 223     /**
 224      * Invoked from a retired connection for requests which have been in-flight and need to be re-adjusted
 225      * and forwarded to the successor connection.
 226      *
 227      * @param request Request to be forwarded
 228      * @param callback Original callback
 229      * @throws RequestException when the request is unhandled by the successor
 230      */
 231     final void replayRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback)
 232             throws RequestException {
 233         Preconditions.checkState(successor != null, "%s does not have a successor set", this);
 234
 235         if (successor instanceof LocalProxyTransaction) {
 236             forwardToLocal((LocalProxyTransaction)successor, request, callback);
 237         } else if (successor instanceof RemoteProxyTransaction) {
 238             forwardToRemote((RemoteProxyTransaction)successor, request, callback);
 239         } else {
 240             throw new IllegalStateException("Unhandled successor " + successor);
 241         }
 242     }
 243
 244     abstract void doDelete(final YangInstanceIdentifier path);
 245
 246     abstract void doMerge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data);
 247
 248     abstract void doWrite(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data);
 249
 250     abstract CheckedFuture<Boolean, ReadFailedException> doExists(final YangInstanceIdentifier path);
 251
 252     abstract CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> doRead(
 253             final YangInstanceIdentifier path);
 254
 255     abstract void doSeal();
 256
 257     abstract void doAbort();
 258
 259     abstract TransactionRequest<?> commitRequest(boolean coordinated);
 260
 261     /**
 262      * Invoked from {@link RemoteProxyTransaction} when it replays its successful requests to its successor. There is
 263      * no equivalent of this call from {@link LocalProxyTransaction} because it does not send a request until all
 264      * operations are packaged in the message.
 265      *
 266      * <p>
 267      * Note: this method is invoked by the predecessor on the successor.
 268      *
 269      * @param request Request which needs to be forwarded
 270      * @param callback Callback to be invoked once the request completes
 271      */
 272     abstract void handleForwardedRemoteRequest(TransactionRequest<?> request,
 273             @Nullable Consumer<Response<?, ?>> callback);
 274
 275     /**
 276      * Replay a request originating in this proxy to a successor remote proxy.
 277      */
 278     abstract void forwardToRemote(RemoteProxyTransaction successor, TransactionRequest<?> request,
 279             Consumer<Response<?, ?>> callback) throws RequestException;
 280
 281     /**
 282      * Replay a request originating in this proxy to a successor local proxy.
 283      */
 284     abstract void forwardToLocal(LocalProxyTransaction successor, TransactionRequest<?> request,
 285             Consumer<Response<?, ?>> callback) throws RequestException;
 286 }