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

   1 /*
   2  * Copyright (c) 2020 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.nb.rfc8040.streams.listeners;
   9
  10 import java.io.IOException;
  11 import java.io.Writer;
  12 import java.time.Instant;
  13 import javax.xml.stream.XMLOutputFactory;
  14 import javax.xml.stream.XMLStreamException;
  15 import javax.xml.stream.XMLStreamWriter;
  16 import javax.xml.transform.dom.DOMResult;
  17 import javax.xml.xpath.XPathExpressionException;
  18 import org.eclipse.jdt.annotation.NonNull;
  19 import org.opendaylight.mdsal.dom.api.DOMEvent;
  20 import org.opendaylight.mdsal.dom.api.DOMNotification;
  21 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.md.sal.remote.rev140114.DataChangedNotification;
  22 import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.controller.md.sal.remote.rev140114.data.changed.notification.DataChangeEvent;
  23 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  24 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  25 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  26 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  27 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  28 import org.w3c.dom.Document;
  29 import org.w3c.dom.Element;
  30
  31 abstract class NotificationFormatter extends EventFormatter<DOMNotification> {
  32     private static final String NOTIFICATION_NAMESPACE = "urn:ietf:params:xml:ns:netconf:notification:1.0";
  33     private static final String NOTIFICATION_ELEMENT = "notification";
  34
  35     static final String SAL_REMOTE_NAMESPACE = DataChangedNotification.QNAME.getNamespace().toString();
  36     static final String DATA_CHANGED_NOTIFICATION_ELEMENT = DataChangedNotification.QNAME.getLocalName();
  37     static final String DATA_CHANGE_EVENT_ELEMENT = DataChangeEvent.QNAME.getLocalName();
  38
  39     static final XMLOutputFactory XML_OUTPUT_FACTORY;
  40
  41     static {
  42         XML_OUTPUT_FACTORY = XMLOutputFactory.newFactory();
  43         XML_OUTPUT_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, true);
  44     }
  45
  46     NotificationFormatter() {
  47
  48     }
  49
  50     NotificationFormatter(final String xpathFilter) throws XPathExpressionException {
  51         super(xpathFilter);
  52     }
  53
  54     @Override
  55     final void fillDocument(final Document doc, final EffectiveModelContext schemaContext, final DOMNotification input)
  56             throws IOException {
  57         final var notificationElement = createNotificationElement(doc,
  58             input instanceof DOMEvent domEvent ? domEvent.getEventInstant() : Instant.now());
  59         final var notificationEventElement = doc.createElementNS(SAL_REMOTE_NAMESPACE, "create-notification-stream");
  60         final var dataElement = doc.createElement("notification");
  61         final DOMResult result = new DOMResult(dataElement);
  62         try {
  63             final XMLStreamWriter writer = XML_OUTPUT_FACTORY.createXMLStreamWriter(result);
  64             try {
  65                 writeNotificationBody(XMLStreamNormalizedNodeStreamWriter.create(writer, schemaContext,
  66                         input.getType()), input.getBody());
  67             } finally {
  68                 writer.close();
  69             }
  70         } catch (final XMLStreamException e) {
  71             throw new IOException("Failed to write notification content", e);
  72         }
  73         notificationElement.appendChild(notificationEventElement);
  74         doc.appendChild(notificationElement);
  75     }
  76
  77     static void writeNotificationBody(final NormalizedNodeStreamWriter writer, final ContainerNode body)
  78             throws IOException {
  79         try (NormalizedNodeWriter nodeWriter = NormalizedNodeWriter.forStreamWriter(writer)) {
  80             nodeWriter.write(body);
  81         }
  82     }
  83
  84     /**
  85      * Generating base element of every notification.
  86      *
  87      * @param doc base {@link Document}
  88      * @return element of {@link Document}
  89      */
  90     static @NonNull Element createNotificationElement(final Document doc) {
  91         return createNotificationElement(doc, Instant.now());
  92     }
  93
  94     static @NonNull Element createNotificationElement(final Document doc, final Instant now) {
  95         final var notificationElement = doc.createElementNS(NOTIFICATION_NAMESPACE, NOTIFICATION_ELEMENT);
  96         final Element eventTimeElement = doc.createElement("eventTime");
  97         eventTimeElement.setTextContent(toRFC3339(now));
  98         notificationElement.appendChild(eventTimeElement);
  99         return notificationElement;
 100     }
 101
 102     static @NonNull XMLStreamWriter createStreamWriterWithNotification(final Writer writer, final Instant now)
 103             throws XMLStreamException {
 104         final var xmlStreamWriter = XML_OUTPUT_FACTORY.createXMLStreamWriter(writer);
 105         xmlStreamWriter.setDefaultNamespace(NOTIFICATION_NAMESPACE);
 106
 107         xmlStreamWriter.writeStartElement(NOTIFICATION_NAMESPACE, NOTIFICATION_ELEMENT);
 108         xmlStreamWriter.writeDefaultNamespace(NOTIFICATION_NAMESPACE);
 109
 110         xmlStreamWriter.writeStartElement("eventTime");
 111         xmlStreamWriter.writeCharacters(toRFC3339(now));
 112         xmlStreamWriter.writeEndElement();
 113         return xmlStreamWriter;
 114     }
 115 }