restconf/restconf-nb/src/main/java/org/opendaylight/restconf/server/mdsal/MdsalDatabindProvider.java

   1 /*
   2  * Copyright (c) 2024 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.restconf.server.mdsal;
   9
  10 import static com.google.common.base.Verify.verifyNotNull;
  11
  12 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  13 import java.lang.invoke.MethodHandles;
  14 import java.lang.invoke.VarHandle;
  15 import javax.annotation.PreDestroy;
  16 import javax.inject.Inject;
  17 import javax.inject.Singleton;
  18 import org.eclipse.jdt.annotation.NonNull;
  19 import org.eclipse.jdt.annotation.Nullable;
  20 import org.opendaylight.mdsal.dom.api.DOMSchemaService;
  21 import org.opendaylight.mdsal.dom.api.DOMSchemaService.YangTextSourceExtension;
  22 import org.opendaylight.restconf.server.api.DatabindContext;
  23 import org.opendaylight.restconf.server.spi.DatabindProvider;
  24 import org.opendaylight.yangtools.concepts.Registration;
  25 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  26 import org.osgi.service.component.annotations.Activate;
  27 import org.osgi.service.component.annotations.Component;
  28 import org.osgi.service.component.annotations.Deactivate;
  29 import org.osgi.service.component.annotations.Reference;
  30
  31 /**
  32  * A {@link DatabindProvider} tracking a {@link DOMSchemaService}.
  33  */
  34 @Singleton
  35 @Component(service = { DatabindProvider.class, MdsalDatabindProvider.class })
  36 public final class MdsalDatabindProvider implements DatabindProvider, AutoCloseable {
  37     private static final VarHandle CURRENT_DATABIND;
  38
  39     static {
  40         try {
  41             CURRENT_DATABIND = MethodHandles.lookup()
  42                 .findVarHandle(MdsalDatabindProvider.class, "currentDatabind", DatabindContext.class);
  43         } catch (NoSuchFieldException | IllegalAccessException e) {
  44             throw new ExceptionInInitializerError(e);
  45         }
  46     }
  47
  48     private final @Nullable YangTextSourceExtension sourceProvider;
  49     private final Registration reg;
  50
  51     @SuppressFBWarnings(value = "URF_UNREAD_FIELD", justification = "https://github.com/spotbugs/spotbugs/issues/2749")
  52     private volatile DatabindContext currentDatabind;
  53
  54     @Inject
  55     @Activate
  56     public MdsalDatabindProvider(@Reference final DOMSchemaService schemaService) {
  57         sourceProvider = schemaService.extension(YangTextSourceExtension.class);
  58         currentDatabind = DatabindContext.ofModel(schemaService.getGlobalContext());
  59         reg = schemaService.registerSchemaContextListener(this::onModelContextUpdated);
  60     }
  61
  62     @PreDestroy
  63     @Deactivate
  64     @Override
  65     public void close() {
  66         reg.close();
  67     }
  68
  69     @Override
  70     public DatabindContext currentDatabind() {
  71         return verifyNotNull((@NonNull DatabindContext) CURRENT_DATABIND.getAcquire(this));
  72     }
  73
  74     @Nullable YangTextSourceExtension sourceProvider() {
  75         return sourceProvider;
  76     }
  77
  78     private void onModelContextUpdated(final EffectiveModelContext newModelContext) {
  79         final var local = currentDatabind;
  80         if (!newModelContext.equals(local.modelContext())) {
  81             CURRENT_DATABIND.setRelease(this, DatabindContext.ofModel(newModelContext));
  82         }
  83     }
  84 }