/*
* Copyright (c) 2016 Brocade Communications Systems, Inc. and others. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.controller.blueprint.ext;
import com.google.common.collect.ImmutableList;
import com.google.common.io.Resources;
import java.io.IOException;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ConcurrentSkipListSet;
import org.osgi.framework.Bundle;
import org.osgi.framework.BundleEvent;
import org.osgi.framework.ServiceReference;
import org.osgi.service.blueprint.container.ComponentDefinitionException;
import org.osgi.util.tracker.BundleTracker;
import org.osgi.util.tracker.BundleTrackerCustomizer;
import org.osgi.util.tracker.ServiceTracker;
import org.osgi.util.tracker.ServiceTrackerCustomizer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Factory metadata corresponding to the "specific-reference-list" element that obtains a specific list
* of service instances from the OSGi registry for a given interface. The specific list is learned by first
* extracting the list of expected service types by inspecting RESOLVED bundles for a resource file under
* META-INF/services with the same name as the given interface. The type(s) listed in the resource file
* must match the "type" property of the advertised service(s). In this manner, an app bundle announces the
* service type(s) that it will advertise so that this class knows which services to expect up front. Once
* all the expected services are obtained, the container is notified that all dependencies of this component
* factory are satisfied.
*
* @author Thomas Pantelis
*/
class SpecificReferenceListMetadata extends AbstractDependentComponentFactoryMetadata {
private static final Logger LOG = LoggerFactory.getLogger(SpecificReferenceListMetadata.class);
private final String interfaceName;
private final String serviceResourcePath;
private final Collection<String> expectedServiceTypes = new ConcurrentSkipListSet<>();
private final Collection<String> retrievedServiceTypes = new ConcurrentSkipListSet<>();
private final Collection<Object> retrievedServices = Collections.synchronizedList(new ArrayList<>());
private volatile BundleTracker<Bundle> bundleTracker;
private volatile ServiceTracker<Object, Object> serviceTracker;
SpecificReferenceListMetadata(String id, String interfaceName) {
super(id);
this.interfaceName = interfaceName;
serviceResourcePath = "META-INF/services/" + interfaceName;
}
@Override
protected void startTracking() {
BundleTrackerCustomizer<Bundle> bundleListener = new BundleTrackerCustomizer<Bundle>() {
@Override
public Bundle addingBundle(Bundle bundle, BundleEvent event) {
bundleAdded(bundle);
return bundle;
}
@Override
public void modifiedBundle(Bundle bundle, BundleEvent event, Bundle object) {
}
@Override
public void removedBundle(Bundle bundle, BundleEvent event, Bundle object) {
}
};
bundleTracker = new BundleTracker<>(container().getBundleContext(), Bundle.RESOLVED | Bundle.STARTING
| Bundle.STOPPING | Bundle.ACTIVE, bundleListener);
// This will get the list of all current RESOLVED+ bundles.
bundleTracker.open();
if (expectedServiceTypes.isEmpty()) {
setSatisfied();
return;
}
ServiceTrackerCustomizer<Object, Object> serviceListener = new ServiceTrackerCustomizer<Object, Object>() {
@Override
public Object addingService(ServiceReference<Object> reference) {
return serviceAdded(reference);
}
@Override
public void modifiedService(ServiceReference<Object> reference, Object service) {
}
@Override
public void removedService(ServiceReference<Object> reference, Object service) {
container().getBundleContext().ungetService(reference);
}
};
setDependencyDesc(interfaceName + " services with types " + expectedServiceTypes);
serviceTracker = new ServiceTracker<>(container().getBundleContext(), interfaceName, serviceListener);
serviceTracker.open();
}
private void bundleAdded(Bundle bundle) {
URL resource = bundle.getEntry(serviceResourcePath);
if (resource == null) {
return;
}
LOG.debug("{}: Found {} resource in bundle {}", logName(), resource, bundle.getSymbolicName());
try {
for (String line : Resources.readLines(resource, StandardCharsets.UTF_8)) {
int ci = line.indexOf('#');
if (ci >= 0) {
line = line.substring(0, ci);
}
line = line.trim();
if (line.isEmpty()) {
continue;
}
String serviceType = line;
LOG.debug("{}: Retrieved service type {}", logName(), serviceType);
expectedServiceTypes.add(serviceType);
}
} catch (IOException e) {
setFailure(String.format("%s: Error reading resource %s from bundle %s", logName(), resource,
bundle.getSymbolicName()), e);
}
}
private Object serviceAdded(ServiceReference<Object> reference) {
Object service = container().getBundleContext().getService(reference);
Object serviceType = reference.getProperty(OpendaylightNamespaceHandler.TYPE_ATTR);
LOG.debug("{}: Service type {} added from bundle {}", logName(), serviceType,
reference.getBundle().getSymbolicName());
if (serviceType == null) {
LOG.error("{}: Missing OSGi service property '{}' for service interface {} in bundle {}", logName(),
OpendaylightNamespaceHandler.TYPE_ATTR, interfaceName, reference.getBundle().getSymbolicName());
return service;
}
if (!expectedServiceTypes.contains(serviceType)) {
LOG.error("{}: OSGi service property '{}' for service interface {} in bundle {} was not found in the "
+ "expected service types {} obtained via {} bundle resources. Is the bundle resource missing or "
+ "the service type misspelled?", logName(), OpendaylightNamespaceHandler.TYPE_ATTR, interfaceName,
reference.getBundle().getSymbolicName(), expectedServiceTypes, serviceResourcePath);
return service;
}
// If already satisfied, meaning we got all initial services, then a new bundle must've been
// dynamically installed or a prior service's blueprint container was restarted, in which case we
// restart our container.
if (isSatisfied()) {
restartContainer();
} else {
retrievedServiceTypes.add(serviceType.toString());
retrievedServices.add(service);
if (retrievedServiceTypes.equals(expectedServiceTypes)) {
LOG.debug("{}: Got all expected service types", logName());
setSatisfied();
} else {
Set<String> remaining = new HashSet<>(expectedServiceTypes);
remaining.removeAll(retrievedServiceTypes);
setDependencyDesc(interfaceName + " services with types " + remaining);
}
}
return service;
}
@Override
public Object create() throws ComponentDefinitionException {
LOG.debug("{}: In create: interfaceName: {}", logName(), interfaceName);
super.onCreate();
LOG.debug("{}: create returning service list {}", logName(), retrievedServices);
synchronized (retrievedServices) {
return ImmutableList.copyOf(retrievedServices);
}
}
@Override
public void destroy(Object instance) {
super.destroy(instance);
if (bundleTracker != null) {
bundleTracker.close();
bundleTracker = null;
}
if (serviceTracker != null) {
serviceTracker.close();
serviceTracker = null;
}
}
@Override
public String toString() {
StringBuilder builder = new StringBuilder();
builder.append("SpecificReferenceListMetadata [interfaceName=").append(interfaceName)
.append(", serviceResourcePath=").append(serviceResourcePath).append("]");
return builder.toString();
}
}