opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/ShardManager.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.ActorPath;
  12 import akka.actor.ActorRef;
  13 import akka.actor.Address;
  14 import akka.actor.OneForOneStrategy;
  15 import akka.actor.Props;
  16 import akka.actor.SupervisorStrategy;
  17 import akka.cluster.ClusterEvent;
  18 import akka.japi.Creator;
  19 import akka.japi.Function;
  20 import com.google.common.base.Preconditions;
  21 import org.opendaylight.controller.cluster.datastore.messages.FindLocalShard;
  22 import org.opendaylight.controller.cluster.datastore.messages.FindPrimary;
  23 import org.opendaylight.controller.cluster.datastore.messages.LocalShardFound;
  24 import org.opendaylight.controller.cluster.datastore.messages.LocalShardNotFound;
  25 import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
  26 import org.opendaylight.controller.cluster.datastore.messages.PrimaryFound;
  27 import org.opendaylight.controller.cluster.datastore.messages.PrimaryNotFound;
  28 import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContext;
  29 import scala.concurrent.duration.Duration;
  30
  31 import java.util.HashMap;
  32 import java.util.List;
  33 import java.util.Map;
  34
  35 /**
  36  * The ShardManager has the following jobs,
  37  * <ul>
  38  * <li> Create all the local shard replicas that belong on this cluster member
  39  * <li> Find the address of the local shard
  40  * <li> Find the primary replica for any given shard
  41  * <li> Monitor the cluster members and store their addresses
  42  * <ul>
  43  */
  44 public class ShardManager extends AbstractUntypedActor {
  45
  46     // Stores a mapping between a member name and the address of the member
  47     // Member names look like "member-1", "member-2" etc and are as specified
  48     // in configuration
  49     private final Map<String, Address> memberNameToAddress = new HashMap<>();
  50
  51     // Stores a mapping between a shard name and it's corresponding information
  52     // Shard names look like inventory, topology etc and are as specified in
  53     // configuration
  54     private final Map<String, ShardInformation> localShards = new HashMap<>();
  55
  56     // The type of a ShardManager reflects the type of the datastore itself
  57     // A data store could be of type config/operational
  58     private final String type;
  59
  60     private final ClusterWrapper cluster;
  61
  62     private final Configuration configuration;
  63
  64     /**
  65      * @param type defines the kind of data that goes into shards created by this shard manager. Examples of type would be
  66      *             configuration or operational
  67      */
  68     private ShardManager(String type, ClusterWrapper cluster, Configuration configuration) {
  69
  70         this.type = Preconditions.checkNotNull(type, "type should not be null");
  71         this.cluster = Preconditions.checkNotNull(cluster, "cluster should not be null");
  72         this.configuration = Preconditions.checkNotNull(configuration, "configuration should not be null");
  73
  74         // Subscribe this actor to cluster member events
  75         cluster.subscribeToMemberEvents(getSelf());
  76
  77         // Create all the local Shards and make them a child of the ShardManager
  78         // TODO: This may need to be initiated when we first get the schema context
  79         createLocalShards();
  80     }
  81
  82     public static Props props(final String type,
  83         final ClusterWrapper cluster,
  84         final Configuration configuration) {
  85         return Props.create(new Creator<ShardManager>() {
  86
  87             @Override
  88             public ShardManager create() throws Exception {
  89                 return new ShardManager(type, cluster, configuration);
  90             }
  91         });
  92     }
  93
  94
  95     @Override
  96     public void handleReceive(Object message) throws Exception {
  97         if (message.getClass().equals(FindPrimary.SERIALIZABLE_CLASS)) {
  98             findPrimary(
  99                 FindPrimary.fromSerializable(message));
 100         } else if(message instanceof FindLocalShard){
 101             findLocalShard((FindLocalShard) message);
 102         } else if (message instanceof UpdateSchemaContext) {
 103             updateSchemaContext(message);
 104         } else if (message instanceof ClusterEvent.MemberUp){
 105             memberUp((ClusterEvent.MemberUp) message);
 106         } else if(message instanceof ClusterEvent.MemberRemoved) {
 107             memberRemoved((ClusterEvent.MemberRemoved) message);
 108         } else if(message instanceof ClusterEvent.UnreachableMember) {
 109             ignoreMessage(message);
 110         } else{
 111           throw new Exception ("Not recognized message received, message="+message);
 112         }
 113
 114     }
 115
 116     private void findLocalShard(FindLocalShard message) {
 117         ShardInformation shardInformation =
 118             localShards.get(message.getShardName());
 119
 120         if(shardInformation != null){
 121             getSender().tell(new LocalShardFound(shardInformation.getActor()), getSelf());
 122             return;
 123         }
 124
 125         getSender().tell(new LocalShardNotFound(message.getShardName()), getSelf());
 126     }
 127
 128     private void ignoreMessage(Object message){
 129         LOG.debug("Unhandled message : " + message);
 130     }
 131
 132     private void memberRemoved(ClusterEvent.MemberRemoved message) {
 133         memberNameToAddress.remove(message.member().roles().head());
 134     }
 135
 136     private void memberUp(ClusterEvent.MemberUp message) {
 137         String memberName = message.member().roles().head();
 138
 139         memberNameToAddress.put(memberName , message.member().address());
 140
 141         for(ShardInformation info : localShards.values()){
 142             String shardName = info.getShardName();
 143             info.updatePeerAddress(getShardActorName(memberName, shardName),
 144                 getShardActorPath(shardName, memberName));
 145         }
 146     }
 147
 148     /**
 149      * Notifies all the local shards of a change in the schema context
 150      *
 151      * @param message
 152      */
 153     private void updateSchemaContext(Object message) {
 154         for(ShardInformation info : localShards.values()){
 155             info.getActor().tell(message,getSelf());
 156         }
 157     }
 158
 159     private void findPrimary(FindPrimary message) {
 160         String shardName = message.getShardName();
 161
 162         List<String> members =
 163             configuration.getMembersFromShardName(shardName);
 164
 165         // First see if the there is a local replica for the shard
 166         ShardInformation info = localShards.get(shardName);
 167         if(info != null) {
 168             ActorPath shardPath = info.getActorPath();
 169             if (shardPath != null) {
 170                 getSender()
 171                     .tell(
 172                         new PrimaryFound(shardPath.toString()).toSerializable(),
 173                         getSelf());
 174                 return;
 175             }
 176         }
 177
 178         if(cluster.getCurrentMemberName() != null) {
 179             members.remove(cluster.getCurrentMemberName());
 180         }
 181
 182         // There is no way for us to figure out the primary (for now) so assume
 183         // that one of the remote nodes is a primary
 184         for(String memberName : members) {
 185             Address address = memberNameToAddress.get(memberName);
 186             if(address != null){
 187                 String path =
 188                     getShardActorPath(shardName, memberName);
 189                 getSender().tell(new PrimaryFound(path).toSerializable(), getSelf());
 190                 return;
 191             }
 192         }
 193         getSender().tell(new PrimaryNotFound(shardName).toSerializable(), getSelf());
 194     }
 195
 196     private String getShardActorPath(String shardName, String memberName) {
 197         Address address = memberNameToAddress.get(memberName);
 198         if(address != null) {
 199             return address.toString() + "/user/shardmanager-" + this.type + "/"
 200                 + getShardActorName(
 201                 memberName, shardName);
 202         }
 203         return null;
 204     }
 205
 206     /**
 207      * Construct the name of the shard actor given the name of the member on
 208      * which the shard resides and the name of the shard
 209      *
 210      * @param memberName
 211      * @param shardName
 212      * @return
 213      */
 214     private String getShardActorName(String memberName, String shardName){
 215         return memberName + "-shard-" + shardName + "-" + this.type;
 216     }
 217
 218     /**
 219      * Create shards that are local to the member on which the ShardManager
 220      * runs
 221      *
 222      */
 223     private void createLocalShards() {
 224         String memberName = this.cluster.getCurrentMemberName();
 225         List<String> memberShardNames =
 226             this.configuration.getMemberShardNames(memberName);
 227
 228         for(String shardName : memberShardNames){
 229             String shardActorName = getShardActorName(memberName, shardName);
 230             Map<String, String> peerAddresses = getPeerAddresses(shardName);
 231             ActorRef actor = getContext()
 232                 .actorOf(Shard.props(shardActorName, peerAddresses),
 233                     shardActorName);
 234             localShards.put(shardName, new ShardInformation(shardName, actor, peerAddresses));
 235         }
 236
 237     }
 238
 239     /**
 240      * Given the name of the shard find the addresses of all it's peers
 241      *
 242      * @param shardName
 243      * @return
 244      */
 245     private Map<String, String> getPeerAddresses(String shardName){
 246
 247         Map<String, String> peerAddresses = new HashMap<>();
 248
 249         List<String> members =
 250             this.configuration.getMembersFromShardName(shardName);
 251
 252         String currentMemberName = this.cluster.getCurrentMemberName();
 253
 254         for(String memberName : members){
 255             if(!currentMemberName.equals(memberName)){
 256                 String shardActorName = getShardActorName(memberName, shardName);
 257                 String path =
 258                     getShardActorPath(shardName, currentMemberName);
 259                 peerAddresses.put(shardActorName, path);
 260             }
 261         }
 262         return peerAddresses;
 263     }
 264
 265
 266     @Override
 267     public SupervisorStrategy supervisorStrategy() {
 268         return new OneForOneStrategy(10, Duration.create("1 minute"),
 269             new Function<Throwable, SupervisorStrategy.Directive>() {
 270                 @Override
 271                 public SupervisorStrategy.Directive apply(Throwable t) {
 272                     return SupervisorStrategy.resume();
 273                 }
 274             }
 275         );
 276
 277     }
 278
 279     private class ShardInformation {
 280         private final String shardName;
 281         private final ActorRef actor;
 282         private final ActorPath actorPath;
 283         private final Map<String, String> peerAddresses;
 284
 285         private ShardInformation(String shardName, ActorRef actor,
 286             Map<String, String> peerAddresses) {
 287             this.shardName = shardName;
 288             this.actor = actor;
 289             this.actorPath = actor.path();
 290             this.peerAddresses = peerAddresses;
 291         }
 292
 293         public String getShardName() {
 294             return shardName;
 295         }
 296
 297         public ActorRef getActor(){
 298             return actor;
 299         }
 300
 301         public ActorPath getActorPath() {
 302             return actorPath;
 303         }
 304
 305         public Map<String, String> getPeerAddresses() {
 306             return peerAddresses;
 307         }
 308
 309         public void updatePeerAddress(String peerId, String peerAddress){
 310             LOG.info("updatePeerAddress for peer {} with address {}", peerId, peerAddress);
 311             if(peerAddresses.containsKey(peerId)){
 312                 peerAddresses.put(peerId, peerAddress);
 313
 314                 LOG.info("Sending PeerAddressResolved for peer {} with address {} to {}", peerId, peerAddress, actor.path());
 315
 316                 actor
 317                     .tell(new PeerAddressResolved(peerId, peerAddress),
 318                         getSelf());
 319
 320             }
 321         }
 322     }
 323 }