b22829370336e26f0da06c9c344ba1fba9c8add0
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / databroker / actors / dds / LocalProxyTransaction.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 com.google.common.base.Optional;
11 import com.google.common.base.Preconditions;
12 import com.google.common.util.concurrent.CheckedFuture;
13 import com.google.common.util.concurrent.Futures;
14 import java.util.function.Consumer;
15 import javax.annotation.Nullable;
16 import javax.annotation.concurrent.NotThreadSafe;
17 import org.opendaylight.controller.cluster.access.commands.AbortLocalTransactionRequest;
18 import org.opendaylight.controller.cluster.access.commands.AbstractLocalTransactionRequest;
19 import org.opendaylight.controller.cluster.access.commands.CommitLocalTransactionRequest;
20 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionRequest;
21 import org.opendaylight.controller.cluster.access.commands.ExistsTransactionSuccess;
22 import org.opendaylight.controller.cluster.access.commands.ModifyTransactionRequest;
23 import org.opendaylight.controller.cluster.access.commands.ReadTransactionRequest;
24 import org.opendaylight.controller.cluster.access.commands.ReadTransactionSuccess;
25 import org.opendaylight.controller.cluster.access.commands.TransactionPurgeRequest;
26 import org.opendaylight.controller.cluster.access.commands.TransactionRequest;
27 import org.opendaylight.controller.cluster.access.concepts.Response;
28 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
29 import org.opendaylight.controller.cluster.datastore.util.AbstractDataTreeModificationCursor;
30 import org.opendaylight.mdsal.common.api.ReadFailedException;
31 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
32 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
33 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
34 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
35 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
36 import org.slf4j.Logger;
37 import org.slf4j.LoggerFactory;
38
39 /**
40  * An {@link AbstractProxyTransaction} for dispatching a transaction towards a shard leader which is co-located with
41  * the client instance.
42  *
43  * <p>
44  * It requires a {@link DataTreeSnapshot}, which is used to instantiated a new {@link DataTreeModification}. Operations
45  * are then performed on this modification and once the transaction is submitted, the modification is sent to the shard
46  * leader.
47  *
48  * <p>
49  * This class is not thread-safe as usual with transactions. Since it does not interact with the backend until the
50  * transaction is submitted, at which point this class gets out of the picture, this is not a cause for concern.
51  *
52  * @author Robert Varga
53  */
54 @NotThreadSafe
55 abstract class LocalProxyTransaction extends AbstractProxyTransaction {
56     private static final Logger LOG = LoggerFactory.getLogger(LocalProxyTransaction.class);
57
58     private final TransactionIdentifier identifier;
59
60     LocalProxyTransaction(final ProxyHistory parent, final TransactionIdentifier identifier) {
61         super(parent);
62         this.identifier = Preconditions.checkNotNull(identifier);
63     }
64
65     @Override
66     public final TransactionIdentifier getIdentifier() {
67         return identifier;
68     }
69
70     abstract DataTreeSnapshot readOnlyView();
71
72     abstract void applyModifyTransactionRequest(ModifyTransactionRequest request,
73             @Nullable Consumer<Response<?, ?>> callback);
74
75     abstract void replayModifyTransactionRequest(ModifyTransactionRequest request,
76             @Nullable Consumer<Response<?, ?>> callback, long enqueuedTicks);
77
78     @Override
79     final CheckedFuture<Boolean, ReadFailedException> doExists(final YangInstanceIdentifier path) {
80         return Futures.immediateCheckedFuture(readOnlyView().readNode(path).isPresent());
81     }
82
83     @Override
84     final CheckedFuture<Optional<NormalizedNode<?, ?>>, ReadFailedException> doRead(final YangInstanceIdentifier path) {
85         return Futures.immediateCheckedFuture(readOnlyView().readNode(path));
86     }
87
88     @Override
89     final void doAbort() {
90         sendAbort(new AbortLocalTransactionRequest(identifier, localActor()), response -> {
91             LOG.debug("Transaction {} abort completed with {}", identifier, response);
92         });
93     }
94
95     @Override
96     void handleReplayedLocalRequest(final AbstractLocalTransactionRequest<?> request,
97             final Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
98         if (request instanceof AbortLocalTransactionRequest) {
99             enqueueAbort(request, callback, enqueuedTicks);
100         } else {
101             throw new IllegalArgumentException("Unhandled request" + request);
102         }
103     }
104
105     private boolean handleReadRequest(final TransactionRequest<?> request,
106             final @Nullable Consumer<Response<?, ?>> callback) {
107         if (request instanceof ReadTransactionRequest) {
108             final YangInstanceIdentifier path = ((ReadTransactionRequest) request).getPath();
109             final Optional<NormalizedNode<?, ?>> result = readOnlyView().readNode(path);
110             callback.accept(new ReadTransactionSuccess(request.getTarget(), request.getSequence(), result));
111             return true;
112         } else if (request instanceof ExistsTransactionRequest) {
113             final YangInstanceIdentifier path = ((ExistsTransactionRequest) request).getPath();
114             final boolean result = readOnlyView().readNode(path).isPresent();
115             callback.accept(new ExistsTransactionSuccess(request.getTarget(), request.getSequence(), result));
116             return true;
117         } else {
118             return false;
119         }
120     }
121
122     @Override
123     void handleReplayedRemoteRequest(final TransactionRequest<?> request,
124             final @Nullable Consumer<Response<?, ?>> callback, final long enqueuedTicks) {
125         if (request instanceof ModifyTransactionRequest) {
126             replayModifyTransactionRequest((ModifyTransactionRequest) request, callback, enqueuedTicks);
127         } else if (handleReadRequest(request, callback)) {
128             // No-op
129         } else if (request instanceof TransactionPurgeRequest) {
130             enqueuePurge(enqueuedTicks);
131         } else {
132             throw new IllegalArgumentException("Unhandled request " + request);
133         }
134     }
135
136     /**
137      * Remote-to-local equivalent of {@link #handleReplayedRemoteRequest(TransactionRequest, Consumer, long)},
138      * except it is invoked in the forwarding path from
139      * {@link RemoteProxyTransaction#forwardToLocal(LocalProxyTransaction, TransactionRequest, Consumer)}.
140      *
141      * @param request Forwarded request
142      * @param callback Callback to be invoked once the request completes
143      */
144     void handleForwardedRemoteRequest(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
145         if (request instanceof ModifyTransactionRequest) {
146             applyModifyTransactionRequest((ModifyTransactionRequest) request, callback);
147         } else if (handleReadRequest(request, callback)) {
148             // No-op
149         } else if (request instanceof TransactionPurgeRequest) {
150             sendPurge();
151         } else {
152             throw new IllegalArgumentException("Unhandled request " + request);
153         }
154     }
155
156     @Override
157     final void forwardToRemote(final RemoteProxyTransaction successor, final TransactionRequest<?> request,
158                          final Consumer<Response<?, ?>> callback) {
159         if (request instanceof CommitLocalTransactionRequest) {
160             final CommitLocalTransactionRequest req = (CommitLocalTransactionRequest) request;
161             final DataTreeModification mod = req.getModification();
162
163             LOG.debug("Applying modification {} to successor {}", mod, successor);
164             mod.applyToCursor(new AbstractDataTreeModificationCursor() {
165                 @Override
166                 public void write(final PathArgument child, final NormalizedNode<?, ?> data) {
167                     successor.write(current().node(child), data);
168                 }
169
170                 @Override
171                 public void merge(final PathArgument child, final NormalizedNode<?, ?> data) {
172                     successor.merge(current().node(child), data);
173                 }
174
175                 @Override
176                 public void delete(final PathArgument child) {
177                     successor.delete(current().node(child));
178                 }
179             });
180
181             successor.ensureSealed();
182
183             final ModifyTransactionRequest successorReq = successor.commitRequest(req.isCoordinated());
184             successor.sendRequest(successorReq, callback);
185         } else if (request instanceof AbortLocalTransactionRequest) {
186             LOG.debug("Forwarding abort {} to successor {}", request, successor);
187             successor.abort();
188         } else if (request instanceof TransactionPurgeRequest) {
189             LOG.debug("Forwarding purge {} to successor {}", request, successor);
190             successor.sendPurge();
191         } else {
192             throw new IllegalArgumentException("Unhandled request" + request);
193         }
194     }
195
196     @Override
197     void forwardToLocal(final LocalProxyTransaction successor, final TransactionRequest<?> request,
198             final Consumer<Response<?, ?>> callback) {
199         if (request instanceof AbortLocalTransactionRequest) {
200             successor.sendAbort(request, callback);
201         } else if (request instanceof TransactionPurgeRequest) {
202             successor.sendPurge();
203         } else {
204             throw new IllegalArgumentException("Unhandled request" + request);
205         }
206
207         LOG.debug("Forwarded request {} to successor {}", request, successor);
208     }
209
210     void sendAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback) {
211         sendRequest(request, callback);
212     }
213
214     void enqueueAbort(final TransactionRequest<?> request, final Consumer<Response<?, ?>> callback,
215             final long enqueuedTicks) {
216         enqueueRequest(request, callback, enqueuedTicks);
217     }
218 }