Implement DataChangeListener
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / ShardTransaction.java
1 /*
2  * Copyright (c) 2014 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.cluster.datastore;
10
11 import akka.actor.ActorRef;
12 import akka.actor.PoisonPill;
13 import akka.actor.Props;
14 import akka.event.Logging;
15 import akka.event.LoggingAdapter;
16 import akka.japi.Creator;
17 import com.google.common.base.Optional;
18 import com.google.common.util.concurrent.ListenableFuture;
19 import org.opendaylight.controller.cluster.datastore.messages.CloseTransaction;
20 import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionReply;
21 import org.opendaylight.controller.cluster.datastore.messages.DeleteData;
22 import org.opendaylight.controller.cluster.datastore.messages.DeleteDataReply;
23 import org.opendaylight.controller.cluster.datastore.messages.MergeData;
24 import org.opendaylight.controller.cluster.datastore.messages.MergeDataReply;
25 import org.opendaylight.controller.cluster.datastore.messages.ReadData;
26 import org.opendaylight.controller.cluster.datastore.messages.ReadDataReply;
27 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransaction;
28 import org.opendaylight.controller.cluster.datastore.messages.ReadyTransactionReply;
29 import org.opendaylight.controller.cluster.datastore.messages.WriteData;
30 import org.opendaylight.controller.cluster.datastore.messages.WriteDataReply;
31 import org.opendaylight.controller.cluster.datastore.modification.CompositeModification;
32 import org.opendaylight.controller.cluster.datastore.modification.DeleteModification;
33 import org.opendaylight.controller.cluster.datastore.modification.ImmutableCompositeModification;
34 import org.opendaylight.controller.cluster.datastore.modification.MergeModification;
35 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
36 import org.opendaylight.controller.cluster.datastore.modification.WriteModification;
37 import org.opendaylight.controller.sal.core.spi.data.DOMStoreReadWriteTransaction;
38 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
39 import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
40 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
41 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
42
43 import java.util.concurrent.ExecutionException;
44
45 /**
46  * The ShardTransaction Actor represents a remote transaction
47  * <p>
48  * The ShardTransaction Actor delegates all actions to DOMDataReadWriteTransaction
49  * </p>
50  * <p>
51  * Even though the DOMStore and the DOMStoreTransactionChain implement multiple types of transactions
52  * the ShardTransaction Actor only works with read-write transactions. This is just to keep the logic simple. At this
53  * time there are no known advantages for creating a read-only or write-only transaction which may change over time
54  * at which point we can optimize things in the distributed store as well.
55  * </p>
56  * <p>
57  * Handles Messages <br/>
58  * ---------------- <br/>
59  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.ReadData}
60  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.WriteData}
61  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.MergeData}
62  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.DeleteData}
63  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.ReadyTransaction}
64  * <li> {@link org.opendaylight.controller.cluster.datastore.messages.CloseTransaction}
65  * </p>
66  */
67 public class ShardTransaction extends AbstractUntypedActor {
68
69     private final ActorRef shardActor;
70
71     // FIXME : see below
72     // If transactionChain is not null then this transaction is part of a
73     // transactionChain. Not really clear as to what that buys us
74     private final DOMStoreTransactionChain transactionChain;
75
76     private final DOMStoreReadWriteTransaction transaction;
77
78     private final MutableCompositeModification modification =
79         new MutableCompositeModification();
80
81     private final LoggingAdapter log =
82         Logging.getLogger(getContext().system(), this);
83
84     public ShardTransaction(DOMStoreReadWriteTransaction transaction,
85         ActorRef shardActor) {
86         this(null, transaction, shardActor);
87     }
88
89     public ShardTransaction(DOMStoreTransactionChain transactionChain, DOMStoreReadWriteTransaction transaction,
90         ActorRef shardActor) {
91         this.transactionChain = transactionChain;
92         this.transaction = transaction;
93         this.shardActor = shardActor;
94     }
95
96
97
98     public static Props props(final DOMStoreReadWriteTransaction transaction,
99         final ActorRef shardActor) {
100         return Props.create(new Creator<ShardTransaction>() {
101
102             @Override
103             public ShardTransaction create() throws Exception {
104                 return new ShardTransaction(transaction, shardActor);
105             }
106         });
107     }
108
109     public static Props props(final DOMStoreTransactionChain transactionChain, final DOMStoreReadWriteTransaction transaction,
110         final ActorRef shardActor) {
111         return Props.create(new Creator<ShardTransaction>() {
112
113             @Override
114             public ShardTransaction create() throws Exception {
115                 return new ShardTransaction(transactionChain, transaction, shardActor);
116             }
117         });
118     }
119
120
121     @Override
122     public void handleReceive(Object message) throws Exception {
123         if (message instanceof ReadData) {
124             readData((ReadData) message);
125         } else if (message instanceof WriteData) {
126             writeData((WriteData) message);
127         } else if (message instanceof MergeData) {
128             mergeData((MergeData) message);
129         } else if (message instanceof DeleteData) {
130             deleteData((DeleteData) message);
131         } else if (message instanceof ReadyTransaction) {
132             readyTransaction((ReadyTransaction) message);
133         } else if (message instanceof CloseTransaction) {
134             closeTransaction((CloseTransaction) message);
135         } else if (message instanceof GetCompositedModification) {
136             // This is here for testing only
137             getSender().tell(new GetCompositeModificationReply(
138                 new ImmutableCompositeModification(modification)), getSelf());
139         }
140     }
141
142     private void readData(ReadData message) {
143         final ActorRef sender = getSender();
144         final ActorRef self = getSelf();
145         final InstanceIdentifier path = message.getPath();
146         final ListenableFuture<Optional<NormalizedNode<?, ?>>> future =
147             transaction.read(path);
148
149         future.addListener(new Runnable() {
150             @Override
151             public void run() {
152                 try {
153                     Optional<NormalizedNode<?, ?>> optional = future.get();
154                     if (optional.isPresent()) {
155                         sender.tell(new ReadDataReply(optional.get()), self);
156                     } else {
157                         sender.tell(new ReadDataReply(null), self);
158                     }
159                 } catch (InterruptedException | ExecutionException e) {
160                     log.error(e,
161                         "An exception happened when reading data from path : "
162                             + path.toString());
163                 }
164
165             }
166         }, getContext().dispatcher());
167     }
168
169
170     private void writeData(WriteData message) {
171         modification.addModification(
172             new WriteModification(message.getPath(), message.getData()));
173         transaction.write(message.getPath(), message.getData());
174         getSender().tell(new WriteDataReply(), getSelf());
175     }
176
177     private void mergeData(MergeData message) {
178         modification.addModification(
179             new MergeModification(message.getPath(), message.getData()));
180         transaction.merge(message.getPath(), message.getData());
181         getSender().tell(new MergeDataReply(), getSelf());
182     }
183
184     private void deleteData(DeleteData message) {
185         modification.addModification(new DeleteModification(message.getPath()));
186         transaction.delete(message.getPath());
187         getSender().tell(new DeleteDataReply(), getSelf());
188     }
189
190     private void readyTransaction(ReadyTransaction message) {
191         DOMStoreThreePhaseCommitCohort cohort = transaction.ready();
192         ActorRef cohortActor = getContext().actorOf(
193             ThreePhaseCommitCohort.props(cohort, shardActor, modification));
194         getSender()
195             .tell(new ReadyTransactionReply(cohortActor.path()), getSelf());
196
197     }
198
199     private void closeTransaction(CloseTransaction message) {
200         transaction.close();
201         getSender().tell(new CloseTransactionReply(), getSelf());
202         getSelf().tell(PoisonPill.getInstance(), getSelf());
203     }
204
205
206     // These classes are in here for test purposes only
207
208
209     static class GetCompositedModification {
210
211     }
212
213
214     static class GetCompositeModificationReply {
215         private final CompositeModification modification;
216
217
218         GetCompositeModificationReply(CompositeModification modification) {
219             this.modification = modification;
220         }
221
222
223         public CompositeModification getModification() {
224             return modification;
225         }
226     }
227 }

©2013 OpenDaylight, A Linux Foundation Collaborative Project. All Rights Reserved.
OpenDaylight is a registered trademark of The OpenDaylight Project, Inc.
Linux Foundation and OpenDaylight are registered trademarks of the Linux Foundation.
Linux is a registered trademark of Linus Torvalds.