restconf/restconf-nb/src/main/java/org/opendaylight/restconf/server/mdsal/streams/dtcl/DataTreeChangeSource.java

   1 /*
   2  * Copyright (c) 2014, 2016 Cisco Systems, Inc. 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.streams.dtcl;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.annotations.VisibleForTesting;
  13 import com.google.common.base.MoreObjects.ToStringHelper;
  14 import com.google.common.collect.ImmutableMap;
  15 import java.time.Instant;
  16 import java.util.List;
  17 import org.eclipse.jdt.annotation.NonNull;
  18 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  19 import org.opendaylight.mdsal.dom.api.DOMDataBroker.DataTreeChangeExtension;
  20 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeListener;
  21 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  22 import org.opendaylight.restconf.server.spi.DatabindProvider;
  23 import org.opendaylight.restconf.server.spi.RestconfStream;
  24 import org.opendaylight.restconf.server.spi.RestconfStream.EncodingName;
  25 import org.opendaylight.restconf.server.spi.RestconfStream.Sink;
  26 import org.opendaylight.restconf.server.spi.RestconfStream.Source;
  27 import org.opendaylight.yangtools.concepts.Registration;
  28 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  29 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidate;
  30
  31 /**
  32  * A {@link RestconfStream} reporting changes on a particular data tree.
  33  */
  34 @VisibleForTesting
  35 public final class DataTreeChangeSource extends Source<List<DataTreeCandidate>> {
  36     private static final ImmutableMap<EncodingName, DataTreeCandidateFormatterFactory> ENCODINGS = ImmutableMap.of(
  37         EncodingName.RFC8040_JSON, JSONDataTreeCandidateFormatter.FACTORY,
  38         EncodingName.RFC8040_XML, XMLDataTreeCandidateFormatter.FACTORY);
  39
  40     private final @NonNull DataTreeChangeExtension changeService;
  41     private final @NonNull DatabindProvider databindProvider;
  42     private final @NonNull LogicalDatastoreType datastore;
  43     private final @NonNull YangInstanceIdentifier path;
  44
  45     public DataTreeChangeSource(final DatabindProvider databindProvider, final DataTreeChangeExtension changeService,
  46             final LogicalDatastoreType datastore, final YangInstanceIdentifier path) {
  47         super(ENCODINGS);
  48         this.databindProvider = requireNonNull(databindProvider);
  49         this.changeService = requireNonNull(changeService);
  50         this.datastore = requireNonNull(datastore);
  51         this.path = requireNonNull(path);
  52     }
  53
  54     @Override
  55     protected Registration start(final Sink<List<DataTreeCandidate>> sink) {
  56         return changeService.registerTreeChangeListener(DOMDataTreeIdentifier.of(datastore, path),
  57             new DOMDataTreeChangeListener() {
  58                 @Override
  59                 public void onDataTreeChanged(final List<DataTreeCandidate> changes) {
  60                     // FIXME: format one change at a time?
  61                     sink.publish(databindProvider.currentDatabind().modelContext(), changes, Instant.now());
  62                 }
  63
  64                 @Override
  65                 public void onInitialData() {
  66                     // No-op
  67                 }
  68             });
  69     }
  70
  71     @Override
  72     protected ToStringHelper addToStringAttributes(final ToStringHelper helper) {
  73         return super.addToStringAttributes(helper.add("path", path));
  74     }
  75 }