restconf/restconf-nb/src/main/java/org/opendaylight/restconf/nb/rfc8040/streams/listeners/ListenerAdapter.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.nb.rfc8040.streams.listeners;
   9
  10 import com.google.common.annotations.VisibleForTesting;
  11 import java.time.Instant;
  12 import java.util.Collection;
  13 import java.util.List;
  14 import java.util.Optional;
  15 import java.util.stream.Collectors;
  16 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  17 import org.opendaylight.mdsal.dom.api.ClusteredDOMDataTreeChangeListener;
  18 import org.opendaylight.mdsal.dom.api.DOMDataBroker;
  19 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeService;
  20 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  21 import org.opendaylight.yang.gen.v1.urn.sal.restconf.event.subscription.rev140708.NotificationOutputTypeGrouping.NotificationOutputType;
  22 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  23 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  24 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidate;
  25 import org.slf4j.Logger;
  26 import org.slf4j.LoggerFactory;
  27
  28 /**
  29  * {@link ListenerAdapter} is responsible to track events, which occurred by changing data in data source.
  30  */
  31 public class ListenerAdapter extends AbstractCommonSubscriber<YangInstanceIdentifier, Collection<DataTreeCandidate>>
  32         implements ClusteredDOMDataTreeChangeListener {
  33     private static final Logger LOG = LoggerFactory.getLogger(ListenerAdapter.class);
  34     private static final DataTreeCandidateFormatterFactory JSON_FORMATTER_FACTORY =
  35             JSONDataTreeCandidateFormatter.createFactory(JSONCodecFactorySupplier.RFC7951);
  36
  37     /**
  38      * Creates new {@link ListenerAdapter} listener specified by path and stream name and register for subscribing.
  39      *
  40      * @param path       Path to data in data store.
  41      * @param streamName The name of the stream.
  42      * @param outputType Type of output on notification (JSON, XML).
  43      */
  44     @VisibleForTesting
  45     public ListenerAdapter(final YangInstanceIdentifier path, final String streamName,
  46             final NotificationOutputType outputType) {
  47         super(path.getLastPathArgument().getNodeType(), streamName, path, outputType, getFormatterFactory(outputType));
  48     }
  49
  50     private static DataTreeCandidateFormatterFactory getFormatterFactory(final NotificationOutputType outputType) {
  51         switch (outputType) {
  52             case JSON:
  53                 return JSON_FORMATTER_FACTORY;
  54             case XML:
  55                 return XMLDataTreeCandidateFormatter.FACTORY;
  56             default:
  57                 throw new IllegalArgumentException("Unsupported outputType" + outputType);
  58         }
  59     }
  60
  61     @Override
  62     public void onInitialData() {
  63         // No-op
  64     }
  65
  66     @Override
  67     @SuppressWarnings("checkstyle:IllegalCatch")
  68     public void onDataTreeChanged(final List<DataTreeCandidate> dataTreeCandidates) {
  69         final Instant now = Instant.now();
  70         if (!checkStartStop(now)) {
  71             return;
  72         }
  73
  74         final Optional<String> maybeData;
  75         try {
  76             maybeData = formatter().eventData(schemaHandler.get(), dataTreeCandidates, now, getLeafNodesOnly(),
  77                     isSkipNotificationData());
  78         } catch (final Exception e) {
  79             LOG.error("Failed to process notification {}",
  80                     dataTreeCandidates.stream().map(Object::toString).collect(Collectors.joining(",")), e);
  81             return;
  82         }
  83
  84         if (maybeData.isPresent()) {
  85             post(maybeData.get());
  86         }
  87     }
  88
  89     /**
  90      * Get path pointed to data in data store.
  91      *
  92      * @return Path pointed to data in data store.
  93      */
  94     public YangInstanceIdentifier getPath() {
  95         return path();
  96     }
  97
  98     /**
  99      * Register data change listener in DOM data broker and set it to listener on stream.
 100      *
 101      * @param domDataBroker data broker for register data change listener
 102      * @param datastore     {@link LogicalDatastoreType}
 103      */
 104     public final synchronized void listen(final DOMDataBroker domDataBroker, final LogicalDatastoreType datastore) {
 105         if (!isListening()) {
 106             final DOMDataTreeChangeService changeService = domDataBroker.getExtensions()
 107                 .getInstance(DOMDataTreeChangeService.class);
 108             if (changeService == null) {
 109                 throw new UnsupportedOperationException("DOMDataBroker does not support the DOMDataTreeChangeService");
 110             }
 111
 112             setRegistration(changeService.registerDataTreeChangeListener(
 113                 new DOMDataTreeIdentifier(datastore, getPath()), this));
 114         }
 115     }
 116 }