* 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.netconf.confignetconfconnector.osgi;
-/**
- * Yang store OSGi service
- */
-public interface YangStoreService {
+import com.google.common.base.Function;
+import com.google.common.collect.Collections2;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+import java.lang.ref.SoftReference;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.atomic.AtomicReference;
+import org.opendaylight.controller.config.yangjmxgenerator.ModuleMXBeanEntry;
+import org.opendaylight.controller.netconf.api.Capability;
+import org.opendaylight.controller.netconf.api.monitoring.CapabilityListener;
+import org.opendaylight.controller.netconf.notifications.BaseNetconfNotificationListener;
+import org.opendaylight.controller.netconf.notifications.BaseNotificationPublisherRegistration;
+import org.opendaylight.controller.netconf.notifications.NetconfNotificationCollector;
+import org.opendaylight.controller.netconf.util.capability.YangModuleCapability;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Uri;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChangeBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.changed.by.parms.ChangedByBuilder;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.changed.by.parms.changed.by.server.or.user.ServerBuilder;
+import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.model.api.Module;
+import org.opendaylight.yangtools.yang.model.api.ModuleIdentifier;
+import org.opendaylight.yangtools.yang.model.api.SchemaContextProvider;
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.ServiceReference;
+import org.osgi.util.tracker.ServiceTracker;
+import org.osgi.util.tracker.ServiceTrackerCustomizer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class YangStoreService implements YangStoreContext {
+
+ private static final Logger LOG = LoggerFactory.getLogger(YangStoreService.class);
/**
- * Module entry objects mapped to module names and namespaces.
+ * This is a rather interesting locking model. We need to guard against both the
+ * cache expiring from GC and being invalidated by schema context change. The
+ * context can change while we are doing processing, so we do not want to block
+ * it, so no synchronization can happen on the methods.
+ *
+ * So what we are doing is the following:
+ *
+ * We synchronize with GC as usual, using a SoftReference.
*
- * @return actual view of what is available in OSGi service registry.
+ * The atomic reference is used to synchronize with {@link #refresh()}, e.g. when
+ * refresh happens, it will push a SoftReference(null), e.g. simulate the GC. Now
+ * that may happen while the getter is already busy acting on the old schema context,
+ * so it needs to understand that a refresh has happened and retry. To do that, it
+ * attempts a CAS operation -- if it fails, in knows that the SoftReference has
+ * been replaced and thus it needs to retry.
+ *
+ * Note that {@link #getYangStoreSnapshot()} will still use synchronize() internally
+ * to stop multiple threads doing the same work.
+ */
+ private final AtomicReference<SoftReference<YangStoreSnapshot>> ref =
+ new AtomicReference<>(new SoftReference<YangStoreSnapshot>(null));
+
+ private final SchemaContextProvider schemaContextProvider;
+ private final BaseNetconfNotificationListener notificationPublisher;
+
+ private final ExecutorService notificationExecutor = Executors.newSingleThreadExecutor(new ThreadFactory() {
+ @Override
+ public Thread newThread(final Runnable r) {
+ return new Thread(r, "config-netconf-connector-capability-notifications");
+ }
+ });
+
+ private final Set<CapabilityListener> listeners = Collections.synchronizedSet(new HashSet<CapabilityListener>());
+
+ public YangStoreService(final SchemaContextProvider schemaContextProvider, final BundleContext context) {
+ this(schemaContextProvider, new NotificationCollectorTracker(context));
+ }
+
+ public YangStoreService(final SchemaContextProvider schemaContextProvider, final BaseNetconfNotificationListener notificationHandler) {
+ this.schemaContextProvider = schemaContextProvider;
+ this.notificationPublisher = notificationHandler;
+ }
+
+ private synchronized YangStoreContext getYangStoreSnapshot() {
+ SoftReference<YangStoreSnapshot> r = ref.get();
+ YangStoreSnapshot ret = r.get();
+
+ while (ret == null) {
+ // We need to be compute a new value
+ ret = new YangStoreSnapshot(schemaContextProvider.getSchemaContext());
+
+ if (!ref.compareAndSet(r, new SoftReference<>(ret))) {
+ LOG.debug("Concurrent refresh detected, recomputing snapshot");
+ r = ref.get();
+ ret = null;
+ }
+ }
+
+ return ret;
+ }
+
+ @Override
+ public Map<String, Map<String, ModuleMXBeanEntry>> getModuleMXBeanEntryMap() {
+ return getYangStoreSnapshot().getModuleMXBeanEntryMap();
+ }
+
+ @Override
+ public Map<QName, Map<String, ModuleMXBeanEntry>> getQNamesToIdentitiesToModuleMXBeanEntries() {
+ return getYangStoreSnapshot().getQNamesToIdentitiesToModuleMXBeanEntries();
+ }
+
+ @Override
+ public Set<Module> getModules() {
+ return getYangStoreSnapshot().getModules();
+ }
+
+ @Override
+ public String getModuleSource(final ModuleIdentifier moduleIdentifier) {
+ return getYangStoreSnapshot().getModuleSource(moduleIdentifier);
+ }
+
+ public void refresh() {
+ final YangStoreSnapshot previous = ref.get().get();
+ ref.set(new SoftReference<YangStoreSnapshot>(null));
+ notificationExecutor.submit(new CapabilityChangeNotifier(previous));
+ }
+
+ public AutoCloseable registerCapabilityListener(final CapabilityListener listener) {
+
+ YangStoreContext context = ref.get().get();
+
+ if(context == null) {
+ context = getYangStoreSnapshot();
+ }
+
+ this.listeners.add(listener);
+ listener.onCapabilitiesAdded(NetconfOperationServiceFactoryImpl.setupCapabilities(context));
+
+ return new AutoCloseable() {
+ @Override
+ public void close() throws Exception {
+ YangStoreService.this.listeners.remove(listener);
+ }
+ };
+ }
+
+ private static final Function<Module, Capability> MODULE_TO_CAPABILITY = new Function<Module, Capability>() {
+ @Override
+ public Capability apply(final Module module) {
+ return new YangModuleCapability(module, module.getSource());
+ }
+ };
+
+ private final class CapabilityChangeNotifier implements Runnable {
+
+ private final YangStoreSnapshot previous;
+
+ public CapabilityChangeNotifier(final YangStoreSnapshot previous) {
+ this.previous = previous;
+ }
+
+ @Override
+ public void run() {
+ final YangStoreContext current = getYangStoreSnapshot();
+
+ if(current.equals(previous) == false) {
+ final Sets.SetView<Module> removed = Sets.difference(previous.getModules(), current.getModules());
+ final Sets.SetView<Module> added = Sets.difference(current.getModules(), previous.getModules());
+
+ // Notify notification manager
+ notificationPublisher.onCapabilityChanged(computeDiff(removed, added));
+
+ // Notify direct capability listener TODO would it not be better if the capability listeners went through notification manager ?
+ for (final CapabilityListener listener : listeners) {
+ listener.onCapabilitiesAdded(Sets.newHashSet(Collections2.transform(added, MODULE_TO_CAPABILITY)));
+ }
+ for (final CapabilityListener listener : listeners) {
+ listener.onCapabilitiesRemoved(Sets.newHashSet(Collections2.transform(removed, MODULE_TO_CAPABILITY)));
+ }
+ }
+ }
+ }
+
+ private static final Function<Module, Uri> MODULE_TO_URI = new Function<Module, Uri>() {
+ @Override
+ public Uri apply(final Module input) {
+ return new Uri(new YangModuleCapability(input, input.getSource()).getCapabilityUri());
+ }
+ };
+
+ static NetconfCapabilityChange computeDiff(final Sets.SetView<Module> removed, final Sets.SetView<Module> added) {
+ final NetconfCapabilityChangeBuilder netconfCapabilityChangeBuilder = new NetconfCapabilityChangeBuilder();
+ netconfCapabilityChangeBuilder.setChangedBy(new ChangedByBuilder().setServerOrUser(new ServerBuilder().setServer(true).build()).build());
+ netconfCapabilityChangeBuilder.setDeletedCapability(Lists.newArrayList(Collections2.transform(removed, MODULE_TO_URI)));
+ netconfCapabilityChangeBuilder.setAddedCapability(Lists.newArrayList(Collections2.transform(added, MODULE_TO_URI)));
+ // TODO modified should be computed ... but why ?
+ netconfCapabilityChangeBuilder.setModifiedCapability(Collections.<Uri>emptyList());
+ return netconfCapabilityChangeBuilder.build();
+ }
+
+
+ /**
+ * Looks for NetconfNotificationCollector service and publishes base netconf notifications if possible
*/
- YangStoreSnapshot getYangStoreSnapshot() throws YangStoreException;
+ private static class NotificationCollectorTracker implements ServiceTrackerCustomizer<NetconfNotificationCollector, NetconfNotificationCollector>, BaseNetconfNotificationListener, AutoCloseable {
+
+ private final BundleContext context;
+ private final ServiceTracker<NetconfNotificationCollector, NetconfNotificationCollector> listenerTracker;
+ private BaseNotificationPublisherRegistration publisherReg;
+
+ public NotificationCollectorTracker(final BundleContext context) {
+ this.context = context;
+ listenerTracker = new ServiceTracker<>(context, NetconfNotificationCollector.class, this);
+ listenerTracker.open();
+ }
+
+ @Override
+ public synchronized NetconfNotificationCollector addingService(final ServiceReference<NetconfNotificationCollector> reference) {
+ closePublisherRegistration();
+ publisherReg = context.getService(reference).registerBaseNotificationPublisher();
+ return null;
+ }
+
+ @Override
+ public synchronized void modifiedService(final ServiceReference<NetconfNotificationCollector> reference, final NetconfNotificationCollector service) {
+ closePublisherRegistration();
+ publisherReg = context.getService(reference).registerBaseNotificationPublisher();
+ }
+
+ @Override
+ public synchronized void removedService(final ServiceReference<NetconfNotificationCollector> reference, final NetconfNotificationCollector service) {
+ closePublisherRegistration();
+ publisherReg = null;
+ }
+
+ private void closePublisherRegistration() {
+ if(publisherReg != null) {
+ publisherReg.close();
+ }
+ }
+
+ @Override
+ public synchronized void close() {
+ closePublisherRegistration();
+ listenerTracker.close();
+ }
+
+ @Override
+ public void onCapabilityChanged(final NetconfCapabilityChange capabilityChange) {
+ if(publisherReg == null) {
+ LOG.warn("Omitting notification due to missing notification service: {}", capabilityChange);
+ return;
+ }
+ publisherReg.onCapabilityChanged(capabilityChange);
+ }
+ }
}
Code Review / controller.git / blobdiff