import akka.japi.Creator;
import akka.japi.Function;
import com.google.common.base.Preconditions;
+import org.opendaylight.controller.cluster.datastore.messages.FindLocalShard;
import org.opendaylight.controller.cluster.datastore.messages.FindPrimary;
+import org.opendaylight.controller.cluster.datastore.messages.LocalShardFound;
+import org.opendaylight.controller.cluster.datastore.messages.LocalShardNotFound;
import org.opendaylight.controller.cluster.datastore.messages.PeerAddressResolved;
import org.opendaylight.controller.cluster.datastore.messages.PrimaryFound;
import org.opendaylight.controller.cluster.datastore.messages.PrimaryNotFound;
/**
* The ShardManager has the following jobs,
- * <p>
+ * <ul>
* <li> Create all the local shard replicas that belong on this cluster member
+ * <li> Find the address of the local shard
* <li> Find the primary replica for any given shard
- * <li> Engage in shard replica elections which decide which replica should be the primary
- * </p>
- * <p/>
- * <h3>>Creation of Shard replicas</h3
- * <p>
- * When the ShardManager is constructed it reads the cluster configuration to find out which shard replicas
- * belong on this member. It finds out the name of the current cluster member from the Akka Clustering Service.
- * </p>
- * <p/>
- * <h3> Replica Elections </h3>
- * <p/>
- * <p>
- * The Shard Manager uses multiple cues to initiate election.
- * <li> When a member of the cluster dies
- * <li> When a local shard replica dies
- * <li> When a local shard replica comes alive
- * </p>
+ * <li> Monitor the cluster members and store their addresses
+ * <ul>
*/
public class ShardManager extends AbstractUntypedActor {
// Stores a mapping between a member name and the address of the member
+ // Member names look like "member-1", "member-2" etc and are as specified
+ // in configuration
private final Map<String, Address> memberNameToAddress = new HashMap<>();
+ // Stores a mapping between a shard name and it's corresponding information
+ // Shard names look like inventory, topology etc and are as specified in
+ // configuration
private final Map<String, ShardInformation> localShards = new HashMap<>();
-
+ // The type of a ShardManager reflects the type of the datastore itself
+ // A data store could be of type config/operational
private final String type;
private final ClusterWrapper cluster;
if (message.getClass().equals(FindPrimary.SERIALIZABLE_CLASS)) {
findPrimary(
FindPrimary.fromSerializable(message));
-
+ } else if(message instanceof FindLocalShard){
+ findLocalShard((FindLocalShard) message);
} else if (message instanceof UpdateSchemaContext) {
updateSchemaContext(message);
} else if (message instanceof ClusterEvent.MemberUp){
}
+ private void findLocalShard(FindLocalShard message) {
+ ShardInformation shardInformation =
+ localShards.get(message.getShardName());
+
+ if(shardInformation != null){
+ getSender().tell(new LocalShardFound(shardInformation.getActor()), getSelf());
+ return;
+ }
+
+ getSender().tell(new LocalShardNotFound(message.getShardName()), getSelf());
+ }
+
private void ignoreMessage(Object message){
LOG.debug("Unhandled message : " + message);
}
}
}
+ /**
+ * Notifies all the local shards of a change in the schema context
+ *
+ * @param message
+ */
private void updateSchemaContext(Object message) {
for(ShardInformation info : localShards.values()){
info.getActor().tell(message,getSelf());
getSender().tell(new PrimaryNotFound(shardName).toSerializable(), getSelf());
}
- private String
-
-
- getShardActorPath(String shardName, String memberName) {
+ private String getShardActorPath(String shardName, String memberName) {
Address address = memberNameToAddress.get(memberName);
if(address != null) {
return address.toString() + "/user/shardmanager-" + this.type + "/"
return null;
}
+ /**
+ * Construct the name of the shard actor given the name of the member on
+ * which the shard resides and the name of the shard
+ *
+ * @param memberName
+ * @param shardName
+ * @return
+ */
private String getShardActorName(String memberName, String shardName){
return memberName + "-shard-" + shardName + "-" + this.type;
}
- // Create the shards that are local to this member
+ /**
+ * Create shards that are local to the member on which the ShardManager
+ * runs
+ *
+ */
private void createLocalShards() {
String memberName = this.cluster.getCurrentMemberName();
List<String> memberShardNames =
}
+ /**
+ * Given the name of the shard find the addresses of all it's peers
+ *
+ * @param shardName
+ * @return
+ */
private Map<String, String> getPeerAddresses(String shardName){
Map<String, String> peerAddresses = new HashMap<>();