restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/streams/listeners/NotificationListenerAdapter.java

   1 /*
   2  * Copyright (c) 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 static com.google.common.base.Preconditions.checkArgument;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import com.google.common.annotations.VisibleForTesting;
  14 import com.google.common.base.MoreObjects;
  15 import java.time.Instant;
  16 import java.util.Optional;
  17 import javax.xml.xpath.XPathExpressionException;
  18 import org.opendaylight.mdsal.dom.api.DOMNotification;
  19 import org.opendaylight.mdsal.dom.api.DOMNotificationListener;
  20 import org.opendaylight.restconf.common.formatters.JSONNotificationFormatter;
  21 import org.opendaylight.restconf.common.formatters.NotificationFormatter;
  22 import org.opendaylight.restconf.common.formatters.NotificationFormatterFactory;
  23 import org.opendaylight.restconf.common.formatters.XMLNotificationFormatter;
  24 import org.opendaylight.yang.gen.v1.urn.sal.restconf.event.subscription.rev140708.NotificationOutputTypeGrouping.NotificationOutputType;
  25 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  26 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Absolute;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 /**
  31  * {@link NotificationListenerAdapter} is responsible to track events on notifications.
  32  */
  33 public class NotificationListenerAdapter extends AbstractCommonSubscriber implements DOMNotificationListener {
  34
  35     private static final Logger LOG = LoggerFactory.getLogger(NotificationListenerAdapter.class);
  36     private static final NotificationFormatterFactory JSON_FORMATTER_FACTORY = JSONNotificationFormatter.createFactory(
  37             JSONCodecFactorySupplier.RFC7951);
  38
  39     private final String streamName;
  40     private final Absolute path;
  41     private final NotificationOutputType outputType;
  42
  43     @VisibleForTesting NotificationFormatter formatter;
  44
  45
  46     /**
  47      * Set path of listener and stream name.
  48      *
  49      * @param path       Schema path of YANG notification.
  50      * @param streamName Name of the stream.
  51      * @param outputType Type of output on notification (JSON or XML).
  52      */
  53     NotificationListenerAdapter(final Absolute path, final String streamName, final String outputType) {
  54         setLocalNameOfPath(path.lastNodeIdentifier().getLocalName());
  55
  56         this.outputType = NotificationOutputType.forName(requireNonNull(outputType)).get();
  57         this.path = requireNonNull(path);
  58         this.streamName = requireNonNull(streamName);
  59         checkArgument(!streamName.isEmpty());
  60         this.formatter = getFormatterFactory().getFormatter();
  61
  62         LOG.debug("output type: {}, {}", outputType, this.outputType);
  63     }
  64
  65     private NotificationFormatterFactory getFormatterFactory() {
  66         switch (outputType) {
  67             case JSON:
  68                 return JSON_FORMATTER_FACTORY;
  69             case XML:
  70                 return XMLNotificationFormatter.FACTORY;
  71             default:
  72                 throw new IllegalArgumentException("Unsupported outputType " + outputType);
  73         }
  74     }
  75
  76     private NotificationFormatter getFormatter(final String filter) throws XPathExpressionException {
  77         NotificationFormatterFactory factory = getFormatterFactory();
  78         return filter == null || filter.isEmpty() ? factory.getFormatter() : factory.getFormatter(filter);
  79     }
  80
  81     @Override
  82     public void setQueryParams(final Instant start, final Instant stop, final String filter,
  83                                final boolean leafNodesOnly, final boolean skipNotificationData) {
  84         super.setQueryParams(start, stop, filter, leafNodesOnly, skipNotificationData);
  85         try {
  86             this.formatter = getFormatter(filter);
  87         } catch (XPathExpressionException e) {
  88             throw new IllegalArgumentException("Failed to get filter", e);
  89         }
  90     }
  91
  92     /**
  93      * Get output type of this listener.
  94      *
  95      * @return The configured output type (JSON or XML).
  96      */
  97     @Override
  98     public String getOutputType() {
  99         return this.outputType.getName();
 100     }
 101
 102     @Override
 103     @SuppressWarnings("checkstyle:IllegalCatch")
 104     public void onNotification(final DOMNotification notification) {
 105         final Instant now = Instant.now();
 106         if (!checkStartStop(now, this)) {
 107             return;
 108         }
 109
 110         final Optional<String> maybeOutput;
 111         try {
 112             maybeOutput = formatter.eventData(schemaHandler.get(), notification, now, getLeafNodesOnly(),
 113                     isSkipNotificationData());
 114         } catch (Exception e) {
 115             LOG.error("Failed to process notification {}", notification, e);
 116             return;
 117         }
 118         if (maybeOutput.isPresent()) {
 119             post(maybeOutput.get());
 120         }
 121     }
 122
 123     /**
 124      * Get stream name of this listener.
 125      *
 126      * @return The configured stream name.
 127      */
 128     @Override
 129     public String getStreamName() {
 130         return this.streamName;
 131     }
 132
 133     /**
 134      * Get schema path of notification.
 135      *
 136      * @return The configured schema path that points to observing YANG notification schema node.
 137      */
 138     public Absolute getSchemaPath() {
 139         return this.path;
 140     }
 141
 142     @Override
 143     public String toString() {
 144         return MoreObjects.toStringHelper(this)
 145                 .add("path", path)
 146                 .add("stream-name", streamName)
 147                 .add("output-type", outputType)
 148                 .toString();
 149     }
 150 }