/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.stratos.load.balancer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.stratos.load.balancer.context.LoadBalancerContext;
import org.apache.stratos.messaging.domain.tenant.Tenant;
import org.apache.stratos.messaging.domain.topology.Cluster;
import org.apache.stratos.messaging.domain.topology.Service;
import org.apache.stratos.messaging.domain.topology.ServiceType;
import org.apache.stratos.messaging.event.Event;
import org.apache.stratos.messaging.event.tenant.CompleteTenantEvent;
import org.apache.stratos.messaging.event.tenant.TenantSubscribedEvent;
import org.apache.stratos.messaging.event.tenant.TenantUnSubscribedEvent;
import org.apache.stratos.messaging.listener.tenant.CompleteTenantEventListener;
import org.apache.stratos.messaging.listener.tenant.TenantSubscribedEventListener;
import org.apache.stratos.messaging.listener.tenant.TenantUnSubscribedEventListener;
import org.apache.stratos.messaging.message.receiver.tenant.TenantEventReceiver;
import org.apache.stratos.messaging.message.receiver.topology.TopologyManager;
import java.util.HashMap;
import java.util.Map;
/**
* Load balancer tenant receiver updates load balancer context according to
* incoming tenant events.
*/
public class LoadBalancerTenantEventReceiver implements Runnable {
private static final Log log = LogFactory.getLog(LoadBalancerTenantEventReceiver.class);
private final TenantEventReceiver tenantEventReceiver;
private boolean terminated;
public LoadBalancerTenantEventReceiver() {
tenantEventReceiver = new TenantEventReceiver();
addEventListeners();
}
private void addEventListeners() {
tenantEventReceiver.addEventListener(new CompleteTenantEventListener() {
@Override
protected void onEvent(Event event) {
CompleteTenantEvent completeTenantEvent = (CompleteTenantEvent) event;
for (Tenant tenant : completeTenantEvent.getTenants()) {
for (String serviceName : tenant.getServiceSubscriptions()) {
if(isMultiTenantService(serviceName)) {
addTenantSubscriptionToLbContext(serviceName, tenant.getTenantId());
}
}
}
}
});
tenantEventReceiver.addEventListener(new TenantSubscribedEventListener() {
@Override
protected void onEvent(Event event) {
TenantSubscribedEvent tenantSubscribedEvent = (TenantSubscribedEvent) event;
if(log.isDebugEnabled()) {
log.debug(String.format("Tenant subscribed event received: [tenant-id] %d [service] %s",
tenantSubscribedEvent.getTenantId(), tenantSubscribedEvent.getServiceName()));
}
if(isMultiTenantService(tenantSubscribedEvent.getServiceName())) {
addTenantSubscriptionToLbContext(tenantSubscribedEvent.getServiceName(), tenantSubscribedEvent.getTenantId());
}
}
});
tenantEventReceiver.addEventListener(new TenantUnSubscribedEventListener() {
@Override
protected void onEvent(Event event) {
TenantUnSubscribedEvent tenantUnSubscribedEvent = (TenantUnSubscribedEvent) event;
if(log.isDebugEnabled()) {
log.debug(String.format("Tenant un-subscribed event received: [tenant-id] %d [service] %s",
tenantUnSubscribedEvent.getTenantId(), tenantUnSubscribedEvent.getServiceName()));
}
if(isMultiTenantService(tenantUnSubscribedEvent.getServiceName())) {
removeTenantSubscriptionFromLbContext(tenantUnSubscribedEvent.getServiceName(), tenantUnSubscribedEvent.getTenantId());
}
}
});
}
private boolean isMultiTenantService(String serviceName) {
try {
TopologyManager.acquireReadLock();
Service service = TopologyManager.getTopology().getService(serviceName);
if(service != null) {
return (service.getServiceType() == ServiceType.MultiTenant);
}
return false;
}
finally {
TopologyManager.releaseReadLock();
}
}
private void addTenantSubscriptionToLbContext(String serviceName, int tenantId) {
// Find cluster of tenant
Cluster cluster = findCluster(serviceName, tenantId);
if (cluster != null) {
for (String hostName : cluster.getHostNames()) {
// Add hostName, tenantId, cluster to multi-tenant map
Map<Integer, Cluster> clusterMap = LoadBalancerContext.getInstance().getMultiTenantClusterMap().getClusters(hostName);
if (clusterMap == null) {
clusterMap = new HashMap<Integer, Cluster>();
clusterMap.put(tenantId, cluster);
LoadBalancerContext.getInstance().getMultiTenantClusterMap().addClusters(hostName, clusterMap);
} else {
clusterMap.put(tenantId, cluster);
}
if (log.isDebugEnabled()) {
log.debug(String.format("Cluster added to multi-tenant cluster map: [host-name] %s [tenant-id] %d [cluster] %s",
hostName, tenantId, cluster.getClusterId()));
}
}
} else {
if (log.isErrorEnabled()) {
log.error(String.format("Could not find cluster of tenant: [service] %s [tenant-id] %d",
serviceName, tenantId));
}
}
}
private void removeTenantSubscriptionFromLbContext(String serviceName, int tenantId) {
// Find cluster of tenant
Cluster cluster = findCluster(serviceName, tenantId);
if (cluster != null) {
for (String hostName : cluster.getHostNames()) {
LoadBalancerContext.getInstance().getMultiTenantClusterMap().removeClusters(hostName);
if (log.isDebugEnabled()) {
log.debug(String.format("Cluster removed from multi-tenant clusters map: [host-name] %s [tenant-id] %d [cluster] %s",
hostName, tenantId, cluster.getClusterId()));
}
}
} else {
if (log.isErrorEnabled()) {
log.error(String.format("Could not find cluster of tenant: [service] %s [tenant-id] %d",
serviceName, tenantId));
}
}
}
private Cluster findCluster(String serviceName, int tenantId) {
try {
TopologyManager.acquireReadLock();
Service service = TopologyManager.getTopology().getService(serviceName);
if (service == null) {
throw new RuntimeException(String.format("Service not found: %s", serviceName));
}
for (Cluster cluster : service.getClusters()) {
if (cluster.tenantIdInRange(tenantId)) {
return cluster;
}
}
return null;
} finally {
TopologyManager.releaseReadLock();
}
}
@Override
public void run() {
Thread tenantReceiverThread = new Thread(tenantEventReceiver);
tenantReceiverThread.start();
// Keep the thread live until terminated
while (!terminated) {
try {
Thread.sleep(1000);
} catch (InterruptedException ignore) {
}
}
if (log.isInfoEnabled()) {
log.info("Load balancer tenant receiver thread terminated");
}
}
/**
* Terminate load balancer tenant receiver thread.
*/
public void terminate() {
tenantEventReceiver.terminate();
terminated = true;
}
}