/*
* 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.sling.discovery.impl.cluster;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.UUID;
import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Reference;
import org.apache.felix.scr.annotations.Service;
import org.apache.sling.api.resource.LoginException;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.apache.sling.api.resource.ResourceResolverFactory;
import org.apache.sling.discovery.ClusterView;
import org.apache.sling.discovery.InstanceDescription;
import org.apache.sling.discovery.impl.Config;
import org.apache.sling.discovery.impl.common.View;
import org.apache.sling.discovery.impl.common.ViewHelper;
import org.apache.sling.discovery.impl.common.resource.EstablishedClusterView;
import org.apache.sling.discovery.impl.common.resource.IsolatedInstanceDescription;
import org.apache.sling.settings.SlingSettingsService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Default implementation of the ClusterViewService interface.
* <p>
* This class is a reader only - it accesses the repository to read the
* currently established view
*/
@Component
@Service(value = ClusterViewService.class)
public class ClusterViewServiceImpl implements ClusterViewService {
private final Logger logger = LoggerFactory.getLogger(this.getClass());
@Reference
private SlingSettingsService settingsService;
@Reference
private ResourceResolverFactory resourceResolverFactory;
@Reference
private Config config;
/** the cluster view id of the isolated cluster view */
private String isolatedClusterViewId = UUID.randomUUID().toString();
public String getIsolatedClusterViewId() {
return isolatedClusterViewId;
}
private ClusterView getIsolatedClusterView() {
ResourceResolver resourceResolver = null;
try {
resourceResolver = resourceResolverFactory
.getAdministrativeResourceResolver(null);
Resource instanceResource = resourceResolver
.getResource(config.getClusterInstancesPath() + "/"
+ getSlingId());
IsolatedInstanceDescription ownInstance = new IsolatedInstanceDescription(instanceResource,
isolatedClusterViewId, getSlingId());
return ownInstance.getClusterView();
} catch (LoginException e) {
logger.error("Could not do a login: " + e, e);
throw new RuntimeException("Could not do a login", e);
} finally {
if (resourceResolver != null) {
resourceResolver.close();
}
}
}
public String getSlingId() {
if (settingsService==null) {
return null;
}
return settingsService.getSlingId();
}
public boolean contains(final String slingId) {
List<InstanceDescription> localInstances = getClusterView()
.getInstances();
for (Iterator<InstanceDescription> it = localInstances.iterator(); it
.hasNext();) {
InstanceDescription aLocalInstance = it.next();
if (aLocalInstance.getSlingId().equals(slingId)) {
return true;
}
}
return false;
}
public boolean containsAny(Collection<InstanceDescription> listInstances) {
for (Iterator<InstanceDescription> it = listInstances.iterator(); it
.hasNext();) {
InstanceDescription instanceDescription = it.next();
if (contains(instanceDescription.getSlingId())) {
return true;
}
}
return false;
}
public ClusterView getClusterView() {
if (resourceResolverFactory==null) {
logger.warn("getClusterView: no resourceResolverFactory set at the moment.");
return null;
}
ResourceResolver resourceResolver = null;
try {
resourceResolver = resourceResolverFactory
.getAdministrativeResourceResolver(null);
View view = ViewHelper.getEstablishedView(resourceResolver, config);
if (view == null) {
logger.debug("getEstablishedView: no view established at the moment. isolated mode");
return getIsolatedClusterView();
}
EstablishedClusterView clusterViewImpl = new EstablishedClusterView(
config, view, getSlingId());
boolean foundLocal = false;
for (Iterator<InstanceDescription> it = clusterViewImpl
.getInstances().iterator(); it.hasNext();) {
InstanceDescription instance = it.next();
if (instance.isLocal()) {
foundLocal = true;
break;
}
}
if (foundLocal) {
return clusterViewImpl;
} else {
logger.info("getEstablishedView: the existing established view does not incude the local instance yet! Assuming isolated mode. "
+ "If this occurs at runtime - other than at startup - it could cause a pseudo-network-partition, see SLING-3432. "
+ "Consider increasing heartbeatTimeout then!");
return getIsolatedClusterView();
}
} catch (LoginException e) {
logger.error(
"handleEvent: could not log in administratively: " + e, e);
return null;
} finally {
if (resourceResolver != null) {
resourceResolver.close();
}
}
}
}