| /* |
| * Copyright 2014 Open Networking Laboratory |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.onlab.onos.store.service.impl; |
| |
| import java.io.IOException; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| //import net.jodah.expiringmap.ExpiringMap; |
| //import net.jodah.expiringmap.ExpiringMap.ExpirationListener; |
| //import net.jodah.expiringmap.ExpiringMap.ExpirationPolicy; |
| import net.kuujo.copycat.cluster.Member; |
| import net.kuujo.copycat.event.EventHandler; |
| import net.kuujo.copycat.event.LeaderElectEvent; |
| |
| import org.onlab.onos.cluster.ClusterService; |
| import org.onlab.onos.store.cluster.messaging.ClusterCommunicationService; |
| import org.onlab.onos.store.cluster.messaging.ClusterMessage; |
| import org.onlab.onos.store.cluster.messaging.MessageSubject; |
| import org.onlab.onos.store.service.DatabaseService; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Database update event handler. |
| */ |
| public class DatabaseUpdateEventHandler implements |
| DatabaseUpdateEventListener, EventHandler<LeaderElectEvent> { |
| |
| private final Logger log = LoggerFactory.getLogger(getClass()); |
| |
| public static final MessageSubject DATABASE_UPDATES = |
| new MessageSubject("database-update-event"); |
| |
| private DatabaseService databaseService; |
| private ClusterService cluster; |
| private ClusterCommunicationService clusterCommunicator; |
| |
| private final Member localMember; |
| private final AtomicBoolean isLocalMemberLeader = new AtomicBoolean(false); |
| private final Map<String, Map<DatabaseRow, Void>> tableEntryExpirationMap = new HashMap<>(); |
| //private final ExpirationListener<DatabaseRow, Void> expirationObserver = new ExpirationObserver(); |
| |
| DatabaseUpdateEventHandler(Member localMember) { |
| this.localMember = localMember; |
| } |
| |
| @Override |
| public void tableModified(TableModificationEvent event) { |
| DatabaseRow row = new DatabaseRow(event.tableName(), event.key()); |
| Map<DatabaseRow, Void> map = tableEntryExpirationMap.get(event.tableName()); |
| |
| switch (event.type()) { |
| case ROW_DELETED: |
| if (isLocalMemberLeader.get()) { |
| try { |
| clusterCommunicator.broadcast( |
| new ClusterMessage( |
| cluster.getLocalNode().id(), |
| DATABASE_UPDATES, |
| DatabaseStateMachine.SERIALIZER.encode(event))); |
| } catch (IOException e) { |
| log.error("Failed to broadcast a database table modification event.", e); |
| } |
| } |
| break; |
| case ROW_ADDED: |
| case ROW_UPDATED: |
| map.put(row, null); |
| break; |
| default: |
| break; |
| } |
| } |
| |
| @Override |
| public void tableCreated(String tableName, int expirationTimeMillis) { |
| // make this explicit instead of relying on a negative value |
| // to indicate no expiration. |
| if (expirationTimeMillis > 0) { |
| tableEntryExpirationMap.put(tableName, null); |
| /* |
| ExpiringMap.builder() |
| .expiration(expirationTimeMillis, TimeUnit.SECONDS) |
| .expirationListener(expirationObserver) |
| // FIXME: make the expiration policy configurable. |
| .expirationPolicy(ExpirationPolicy.CREATED) |
| .build()); |
| */ |
| } |
| } |
| |
| @Override |
| public void tableDeleted(String tableName) { |
| tableEntryExpirationMap.remove(tableName); |
| } |
| |
| /* |
| private class ExpirationObserver implements ExpirationListener<DatabaseRow, Void> { |
| @Override |
| public void expired(DatabaseRow key, Void value) { |
| try { |
| // TODO: The safety of this check needs to be verified. |
| // Couple of issues: |
| // 1. It is very likely that only one member should attempt deletion of the entry from database. |
| // 2. A potential race condition exists where the entry expires, but before its can be deleted |
| // from the database, a new entry is added or existing entry is updated. |
| // That means ttl and expiration should be for a given version. |
| if (isLocalMemberLeader.get()) { |
| databaseService.remove(key.tableName, key.key); |
| } |
| } catch (Exception e) { |
| log.warn("Failed to delete entry from the database after ttl expiration. Will retry eviction", e); |
| tableEntryExpirationMap.get(key.tableName).put(new DatabaseRow(key.tableName, key.key), null); |
| } |
| } |
| } |
| */ |
| |
| @Override |
| public void handle(LeaderElectEvent event) { |
| if (localMember.equals(event.leader())) { |
| isLocalMemberLeader.set(true); |
| } |
| } |
| |
| private class DatabaseRow { |
| |
| String tableName; |
| String key; |
| |
| public DatabaseRow(String tableName, String key) { |
| this.tableName = tableName; |
| this.key = key; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| if (!(obj instanceof DatabaseRow)) { |
| return false; |
| } |
| DatabaseRow that = (DatabaseRow) obj; |
| |
| return Objects.equals(this.tableName, that.tableName) && |
| Objects.equals(this.key, that.key); |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(tableName, key); |
| } |
| } |
| } |