restconf/restconf-nb-rfc8040/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.Optional;
  14 import java.util.stream.Collectors;
  15 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  16 import org.opendaylight.mdsal.dom.api.ClusteredDOMDataTreeChangeListener;
  17 import org.opendaylight.mdsal.dom.api.DOMDataBroker;
  18 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeService;
  19 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  20 import org.opendaylight.restconf.common.formatters.DataTreeCandidateFormatterFactory;
  21 import org.opendaylight.restconf.common.formatters.JSONDataTreeCandidateFormatter;
  22 import org.opendaylight.restconf.common.formatters.XMLDataTreeCandidateFormatter;
  23 import org.opendaylight.yang.gen.v1.urn.sal.restconf.event.subscription.rev140708.NotificationOutputTypeGrouping.NotificationOutputType;
  24 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  25 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  26 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 /**
  31  * {@link ListenerAdapter} is responsible to track events, which occurred by changing data in data source.
  32  */
  33 public class ListenerAdapter extends AbstractCommonSubscriber<YangInstanceIdentifier, Collection<DataTreeCandidate>>
  34         implements ClusteredDOMDataTreeChangeListener {
  35     private static final Logger LOG = LoggerFactory.getLogger(ListenerAdapter.class);
  36     private static final DataTreeCandidateFormatterFactory JSON_FORMATTER_FACTORY =
  37             JSONDataTreeCandidateFormatter.createFactory(JSONCodecFactorySupplier.RFC7951);
  38
  39     /**
  40      * Creates new {@link ListenerAdapter} listener specified by path and stream name and register for subscribing.
  41      *
  42      * @param path       Path to data in data store.
  43      * @param streamName The name of the stream.
  44      * @param outputType Type of output on notification (JSON, XML).
  45      */
  46     @VisibleForTesting
  47     public ListenerAdapter(final YangInstanceIdentifier path, final String streamName,
  48             final NotificationOutputType outputType) {
  49         super(path.getLastPathArgument().getNodeType(), streamName, path, outputType, getFormatterFactory(outputType));
  50     }
  51
  52     private static DataTreeCandidateFormatterFactory getFormatterFactory(final NotificationOutputType outputType) {
  53         switch (outputType) {
  54             case JSON:
  55                 return JSON_FORMATTER_FACTORY;
  56             case XML:
  57                 return XMLDataTreeCandidateFormatter.FACTORY;
  58             default:
  59                 throw new IllegalArgumentException("Unsupported outputType" + outputType);
  60         }
  61     }
  62
  63     @Override
  64     public void onInitialData() {
  65         // No-op
  66     }
  67
  68     @Override
  69     @SuppressWarnings("checkstyle:IllegalCatch")
  70     public void onDataTreeChanged(final Collection<DataTreeCandidate> dataTreeCandidates) {
  71         final Instant now = Instant.now();
  72         if (!checkStartStop(now)) {
  73             return;
  74         }
  75
  76         final Optional<String> maybeData;
  77         try {
  78             maybeData = formatter().eventData(schemaHandler.get(), dataTreeCandidates, now, getLeafNodesOnly(),
  79                     isSkipNotificationData());
  80         } catch (final Exception e) {
  81             LOG.error("Failed to process notification {}",
  82                     dataTreeCandidates.stream().map(Object::toString).collect(Collectors.joining(",")), e);
  83             return;
  84         }
  85
  86         if (maybeData.isPresent()) {
  87             post(maybeData.get());
  88         }
  89     }
  90
  91     /**
  92      * Get path pointed to data in data store.
  93      *
  94      * @return Path pointed to data in data store.
  95      */
  96     public YangInstanceIdentifier getPath() {
  97         return path();
  98     }
  99
 100     /**
 101      * Register data change listener in DOM data broker and set it to listener on stream.
 102      *
 103      * @param domDataBroker data broker for register data change listener
 104      * @param datastore     {@link LogicalDatastoreType}
 105      */
 106     public final synchronized void listen(final DOMDataBroker domDataBroker, final LogicalDatastoreType datastore) {
 107         if (!isListening()) {
 108             final DOMDataTreeChangeService changeService = domDataBroker.getExtensions()
 109                 .getInstance(DOMDataTreeChangeService.class);
 110             if (changeService == null) {
 111                 throw new UnsupportedOperationException("DOMDataBroker does not support the DOMDataTreeChangeService");
 112             }
 113
 114             setRegistration(changeService.registerDataTreeChangeListener(
 115                 new DOMDataTreeIdentifier(datastore, getPath()), this));
 116         }
 117     }
 118 }