opendaylight/md-sal/sal-remoterpc-connector/src/main/java/org/opendaylight/controller/remote/rpc/registry/gossip/BucketStore.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.remote.rpc.registry.gossip;
  10
  11 import akka.actor.ActorRef;
  12 import akka.actor.ActorRefProvider;
  13 import akka.actor.Address;
  14 import akka.actor.Props;
  15 import akka.actor.UntypedActor;
  16 import akka.cluster.ClusterActorRefProvider;
  17 import akka.event.Logging;
  18 import akka.event.LoggingAdapter;
  19 import org.opendaylight.controller.remote.rpc.utils.ActorUtil;
  20 import org.opendaylight.controller.utils.ConditionalProbe;
  21
  22 import java.util.HashMap;
  23 import java.util.Map;
  24 import java.util.Set;
  25 import java.util.concurrent.ConcurrentHashMap;
  26 import java.util.concurrent.ConcurrentMap;
  27
  28 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetAllBuckets;
  29 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetAllBucketsReply;
  30 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetBucketVersions;
  31 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetBucketVersionsReply;
  32 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetBucketsByMembers;
  33 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetBucketsByMembersReply;
  34 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetLocalBucket;
  35 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.GetLocalBucketReply;
  36 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.UpdateBucket;
  37 import static org.opendaylight.controller.remote.rpc.registry.gossip.Messages.BucketStoreMessages.UpdateRemoteBuckets;
  38
  39 /**
  40  * A store that syncs its data across nodes in the cluster.
  41  * It maintains a {@link org.opendaylight.controller.remote.rpc.registry.gossip.Bucket} per node. Buckets are versioned.
  42  * A node can write ONLY to its bucket. This way, write conflicts are avoided.
  43  * <p>
  44  * Buckets are sync'ed across nodes using Gossip protocol (http://en.wikipedia.org/wiki/Gossip_protocol)<p>
  45  * This store uses a {@link org.opendaylight.controller.remote.rpc.registry.gossip.Gossiper}.
  46  *
  47  */
  48 public class BucketStore extends UntypedActor {
  49
  50     final LoggingAdapter log = Logging.getLogger(getContext().system(), this);
  51
  52     /**
  53      * Bucket owned by the node
  54      */
  55     private BucketImpl localBucket = new BucketImpl();;
  56
  57     /**
  58      * Buckets ownded by other known nodes in the cluster
  59      */
  60     private ConcurrentMap<Address, Bucket> remoteBuckets = new ConcurrentHashMap<>();
  61
  62     /**
  63      * Bucket version for every known node in the cluster including this node
  64      */
  65     private ConcurrentMap<Address, Long> versions = new ConcurrentHashMap<>();
  66
  67     /**
  68      * Cluster address for this node
  69      */
  70     private Address selfAddress;
  71
  72     private ConditionalProbe probe;
  73
  74     @Override
  75     public void preStart(){
  76         ActorRefProvider provider = getContext().provider();
  77         selfAddress = provider.getDefaultAddress();
  78
  79         if ( provider instanceof ClusterActorRefProvider)
  80             getContext().actorOf(Props.create(Gossiper.class).withMailbox(ActorUtil.MAILBOX), "gossiper");
  81     }
  82
  83     @Override
  84     public void onReceive(Object message) throws Exception {
  85
  86         log.debug("Received message: node[{}], message[{}]", selfAddress, message);
  87
  88         if (probe != null) {
  89             probe.tell(message, getSelf());
  90         }
  91
  92         if (message instanceof ConditionalProbe) {
  93             log.info("Received probe {} {}", getSelf(), message);
  94             probe = (ConditionalProbe) message;
  95         } else if (message instanceof UpdateBucket) {
  96             receiveUpdateBucket(((UpdateBucket) message).getBucket());
  97         } else if (message instanceof GetAllBuckets) {
  98             receiveGetAllBucket();
  99         } else if (message instanceof GetLocalBucket) {
 100             receiveGetLocalBucket();
 101         } else if (message instanceof GetBucketsByMembers) {
 102             receiveGetBucketsByMembers(
 103                 ((GetBucketsByMembers) message).getMembers());
 104         } else if (message instanceof GetBucketVersions) {
 105             receiveGetBucketVersions();
 106         } else if (message instanceof UpdateRemoteBuckets) {
 107             receiveUpdateRemoteBuckets(
 108                 ((UpdateRemoteBuckets) message).getBuckets());
 109         } else {
 110             log.debug("Unhandled message [{}]", message);
 111             unhandled(message);
 112         }
 113
 114     }
 115
 116     /**
 117      * Returns a copy of bucket owned by this node
 118      */
 119     private void receiveGetLocalBucket() {
 120         final ActorRef sender = getSender();
 121         GetLocalBucketReply reply = new GetLocalBucketReply(localBucket);
 122         sender.tell(reply, getSelf());
 123     }
 124
 125     /**
 126      * Updates the bucket owned by this node
 127      *
 128      * @param updatedBucket
 129      */
 130     void receiveUpdateBucket(Bucket updatedBucket){
 131
 132         localBucket = (BucketImpl) updatedBucket;
 133         versions.put(selfAddress, localBucket.getVersion());
 134     }
 135
 136     /**
 137      * Returns all the buckets the this node knows about, self owned + remote
 138      */
 139     void receiveGetAllBucket(){
 140         final ActorRef sender = getSender();
 141         sender.tell(new GetAllBucketsReply(getAllBuckets()), getSelf());
 142     }
 143
 144     /**
 145      * Helper to collect all known buckets
 146      *
 147      * @return self owned + remote buckets
 148      */
 149     Map<Address, Bucket> getAllBuckets(){
 150         Map<Address, Bucket> all = new HashMap<>(remoteBuckets.size() + 1);
 151
 152         //first add the local bucket
 153         all.put(selfAddress, localBucket);
 154
 155         //then get all remote buckets
 156         all.putAll(remoteBuckets);
 157
 158         return all;
 159     }
 160
 161     /**
 162      * Returns buckets for requested members that this node knows about
 163      *
 164      * @param members requested members
 165      */
 166     void receiveGetBucketsByMembers(Set<Address> members){
 167         final ActorRef sender = getSender();
 168         Map<Address, Bucket> buckets = getBucketsByMembers(members);
 169         sender.tell(new GetBucketsByMembersReply(buckets), getSelf());
 170     }
 171
 172     /**
 173      * Helper to collect buckets for requested memebers
 174      *
 175      * @param members requested members
 176      * @return buckets for requested memebers
 177      */
 178     Map<Address, Bucket> getBucketsByMembers(Set<Address> members) {
 179         Map<Address, Bucket> buckets = new HashMap<>();
 180
 181         //first add the local bucket if asked
 182         if (members.contains(selfAddress))
 183             buckets.put(selfAddress, localBucket);
 184
 185         //then get buckets for requested remote nodes
 186         for (Address address : members){
 187             if (remoteBuckets.containsKey(address))
 188                 buckets.put(address, remoteBuckets.get(address));
 189         }
 190
 191         return buckets;
 192     }
 193
 194     /**
 195      * Returns versions for all buckets known
 196      */
 197     void receiveGetBucketVersions(){
 198         final ActorRef sender = getSender();
 199         GetBucketVersionsReply reply = new GetBucketVersionsReply(versions);
 200         sender.tell(reply, getSelf());
 201     }
 202
 203     /**
 204      * Update local copy of remote buckets where local copy's version is older
 205      *
 206      * @param receivedBuckets buckets sent by remote
 207      *                        {@link org.opendaylight.controller.remote.rpc.registry.gossip.Gossiper}
 208      */
 209     void receiveUpdateRemoteBuckets(Map<Address, Bucket> receivedBuckets){
 210
 211         if (receivedBuckets == null || receivedBuckets.isEmpty())
 212             return; //nothing to do
 213
 214         //Remote cant update self's bucket
 215         receivedBuckets.remove(selfAddress);
 216
 217         for (Map.Entry<Address, Bucket> entry : receivedBuckets.entrySet()){
 218
 219             Long localVersion = versions.get(entry.getKey());
 220             if (localVersion == null) localVersion = -1L;
 221
 222             Bucket receivedBucket = entry.getValue();
 223
 224             if (receivedBucket == null)
 225                 continue;
 226
 227             Long remoteVersion = receivedBucket.getVersion();
 228             if (remoteVersion == null) remoteVersion = -1L;
 229
 230             //update only if remote version is newer
 231             if ( remoteVersion.longValue() > localVersion.longValue() ) {
 232                 remoteBuckets.put(entry.getKey(), receivedBucket);
 233                 versions.put(entry.getKey(), remoteVersion);
 234             }
 235         }
 236
 237         log.debug("State after update - Local Bucket [{}], Remote Buckets [{}]", localBucket, remoteBuckets);
 238     }
 239
 240     ///
 241     ///Getter Setters
 242     ///
 243
 244     BucketImpl getLocalBucket() {
 245         return localBucket;
 246     }
 247
 248     void setLocalBucket(BucketImpl localBucket) {
 249         this.localBucket = localBucket;
 250     }
 251
 252     ConcurrentMap<Address, Bucket> getRemoteBuckets() {
 253         return remoteBuckets;
 254     }
 255
 256     void setRemoteBuckets(ConcurrentMap<Address, Bucket> remoteBuckets) {
 257         this.remoteBuckets = remoteBuckets;
 258     }
 259
 260     ConcurrentMap<Address, Long> getVersions() {
 261         return versions;
 262     }
 263
 264     void setVersions(ConcurrentMap<Address, Long> versions) {
 265         this.versions = versions;
 266     }
 267
 268     Address getSelfAddress() {
 269         return selfAddress;
 270     }
 271 }