dom/mdsal-dom-schema-osgi/src/main/java/org/opendaylight/mdsal/dom/schema/osgi/impl/OSGiDOMSchemaService.java

   1 /*
   2  * Copyright (c) 2017, 2020 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.mdsal.dom.schema.osgi.impl;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.util.concurrent.ListenableFuture;
  13 import java.util.List;
  14 import java.util.concurrent.CopyOnWriteArrayList;
  15 import java.util.concurrent.atomic.AtomicReference;
  16 import java.util.function.Consumer;
  17 import org.eclipse.jdt.annotation.NonNull;
  18 import org.opendaylight.mdsal.binding.runtime.api.ModuleInfoSnapshot;
  19 import org.opendaylight.mdsal.dom.api.DOMSchemaService;
  20 import org.opendaylight.mdsal.dom.api.DOMYangTextSourceProvider;
  21 import org.opendaylight.mdsal.dom.schema.osgi.OSGiModuleInfoSnapshot;
  22 import org.opendaylight.yangtools.concepts.AbstractRegistration;
  23 import org.opendaylight.yangtools.concepts.Registration;
  24 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  25 import org.opendaylight.yangtools.yang.model.api.source.SourceIdentifier;
  26 import org.opendaylight.yangtools.yang.model.api.source.YangTextSource;
  27 import org.osgi.service.component.ComponentFactory;
  28 import org.osgi.service.component.annotations.Activate;
  29 import org.osgi.service.component.annotations.Component;
  30 import org.osgi.service.component.annotations.Deactivate;
  31 import org.osgi.service.component.annotations.Reference;
  32 import org.osgi.service.component.annotations.ReferenceCardinality;
  33 import org.osgi.service.component.annotations.ReferencePolicy;
  34 import org.osgi.service.component.annotations.ReferencePolicyOption;
  35 import org.slf4j.Logger;
  36 import org.slf4j.LoggerFactory;
  37
  38 /**
  39  * OSGi Service Registry-backed implementation of {@link DOMSchemaService}.
  40  */
  41 @Component(service = DOMSchemaService.class, immediate = true)
  42 public final class OSGiDOMSchemaService implements DOMSchemaService, DOMYangTextSourceProvider {
  43     private static final Logger LOG = LoggerFactory.getLogger(OSGiDOMSchemaService.class);
  44
  45     private final List<Consumer<EffectiveModelContext>> listeners = new CopyOnWriteArrayList<>();
  46     private final AtomicReference<ModuleInfoSnapshot> currentSnapshot = new AtomicReference<>();
  47     private final ComponentFactory<ModelContextListener> listenerFactory;
  48
  49     private boolean deactivated;
  50
  51     @Activate
  52     public OSGiDOMSchemaService(
  53             @Reference(target = "(component.factory=" + ModelContextListener.FACTORY_NAME + ")")
  54             final ComponentFactory<ModelContextListener> listenerFactory) {
  55         this.listenerFactory = requireNonNull(listenerFactory);
  56         LOG.info("DOM Schema services activated");
  57     }
  58
  59     @Deactivate
  60     void deactivate() {
  61         LOG.info("DOM Schema services deactivated");
  62         deactivated = true;
  63     }
  64
  65     @Reference(policy = ReferencePolicy.DYNAMIC, policyOption = ReferencePolicyOption.GREEDY)
  66     void bindSnapshot(final OSGiModuleInfoSnapshot newContext) {
  67         LOG.info("Updating context to generation {}", newContext.getGeneration());
  68         final var snapshot = newContext.getService();
  69         final var modelContext = snapshot.modelContext();
  70         final var previous = currentSnapshot.getAndSet(snapshot);
  71         LOG.debug("Snapshot updated from {} to {}", previous, snapshot);
  72
  73         listeners.forEach(listener -> notifyListener(modelContext, listener));
  74     }
  75
  76     void unbindSnapshot(final OSGiModuleInfoSnapshot oldContext) {
  77         final var snapshot = oldContext.getService();
  78         if (currentSnapshot.compareAndSet(snapshot, null) && !deactivated) {
  79             LOG.info("Lost final generation {}", oldContext.getGeneration());
  80         }
  81     }
  82
  83     @Reference(cardinality = ReferenceCardinality.MULTIPLE, policy = ReferencePolicy.DYNAMIC,
  84             policyOption = ReferencePolicyOption.GREEDY)
  85     void addListener(final Consumer<EffectiveModelContext> listener) {
  86         LOG.trace("Adding listener {}", listener);
  87         listeners.add(listener);
  88         listener.accept(getGlobalContext());
  89     }
  90
  91     void removeListener(final Consumer<EffectiveModelContext> listener) {
  92         LOG.trace("Removing listener {}", listener);
  93         listeners.remove(listener);
  94     }
  95
  96     @Override
  97     public @NonNull EffectiveModelContext getGlobalContext() {
  98         return currentSnapshot.get().modelContext();
  99     }
 100
 101     @Override
 102     public Registration registerSchemaContextListener(final Consumer<EffectiveModelContext> listener) {
 103         final var reg = listenerFactory.newInstance(ModelContextListener.props(listener));
 104         return new AbstractRegistration() {
 105             @Override
 106             protected void removeRegistration() {
 107                 reg.dispose();
 108             }
 109         };
 110     }
 111
 112     @Override
 113     public ListenableFuture<? extends YangTextSource> getSource(final SourceIdentifier sourceIdentifier) {
 114         return currentSnapshot.get().getSource(sourceIdentifier);
 115     }
 116
 117     @SuppressWarnings("checkstyle:illegalCatch")
 118     private static void notifyListener(final @NonNull EffectiveModelContext modelContext,
 119             final Consumer<EffectiveModelContext> listener) {
 120         try {
 121             listener.accept(modelContext);
 122         } catch (RuntimeException e) {
 123             LOG.warn("Failed to notify listener {}", listener, e);
 124         }
 125     }
 126 }