netconf/netconf-notifications-impl/src/main/java/org/opendaylight/netconf/notifications/impl/ops/CreateSubscription.java

   1 /*
   2  * Copyright (c) 2015 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
   9 package org.opendaylight.netconf.notifications.impl.ops;
  10
  11 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.collect.Lists;
  14 import java.util.Date;
  15 import java.util.List;
  16 import org.opendaylight.controller.config.util.xml.DocumentedException;
  17 import org.opendaylight.controller.config.util.xml.XmlElement;
  18 import org.opendaylight.controller.config.util.xml.XmlUtil;
  19 import org.opendaylight.netconf.api.NetconfSession;
  20 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  21 import org.opendaylight.netconf.mapping.api.SessionAwareNetconfOperation;
  22 import org.opendaylight.netconf.notifications.NetconfNotification;
  23 import org.opendaylight.netconf.notifications.NetconfNotificationListener;
  24 import org.opendaylight.netconf.notifications.NetconfNotificationRegistry;
  25 import org.opendaylight.netconf.notifications.NotificationListenerRegistration;
  26 import org.opendaylight.netconf.notifications.impl.NetconfNotificationManager;
  27 import org.opendaylight.netconf.util.mapping.AbstractSingletonNetconfOperation;
  28 import org.opendaylight.netconf.util.messages.SubtreeFilter;
  29 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.CreateSubscriptionInput;
  30 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.StreamNameType;
  31 import org.slf4j.Logger;
  32 import org.slf4j.LoggerFactory;
  33 import org.w3c.dom.Document;
  34 import org.w3c.dom.Element;
  35
  36 /**
  37  * Create subscription listens for create subscription requests and registers notification listeners into notification registry.
  38  * Received notifications are sent to the client right away
  39  */
  40 public class CreateSubscription extends AbstractSingletonNetconfOperation implements SessionAwareNetconfOperation, AutoCloseable {
  41
  42     private static final Logger LOG = LoggerFactory.getLogger(CreateSubscription.class);
  43
  44     static final String CREATE_SUBSCRIPTION = "create-subscription";
  45
  46     private final NetconfNotificationRegistry notifications;
  47     private final List<NotificationListenerRegistration> subscriptions = Lists.newArrayList();
  48     private NetconfSession netconfSession;
  49
  50     public CreateSubscription(final String netconfSessionIdForReporting, final NetconfNotificationRegistry notifications) {
  51         super(netconfSessionIdForReporting);
  52         this.notifications = notifications;
  53     }
  54
  55     @Override
  56     protected Element handleWithNoSubsequentOperations(final Document document, final XmlElement operationElement) throws DocumentedException {
  57         operationElement.checkName(CREATE_SUBSCRIPTION);
  58         operationElement.checkNamespace(CreateSubscriptionInput.QNAME.getNamespace().toString());
  59         // FIXME reimplement using CODEC_REGISTRY and parse everything into generated class instance
  60         // Binding doesn't support anyxml nodes yet, so filter could not be retrieved
  61         // xml -> normalized node -> CreateSubscriptionInput conversion could be slower than current approach
  62
  63         final Optional<XmlElement> filter = operationElement.getOnlyChildElementWithSameNamespaceOptionally("filter");
  64
  65         // Replay not supported
  66         final Optional<XmlElement> startTime = operationElement.getOnlyChildElementWithSameNamespaceOptionally("startTime");
  67         Preconditions.checkArgument(startTime.isPresent() == false, "StartTime element not yet supported");
  68
  69         // Stop time not supported
  70         final Optional<XmlElement> stopTime = operationElement.getOnlyChildElementWithSameNamespaceOptionally("stopTime");
  71         Preconditions.checkArgument(stopTime.isPresent() == false, "StopTime element not yet supported");
  72
  73         final StreamNameType streamNameType = parseStreamIfPresent(operationElement);
  74
  75         Preconditions.checkNotNull(netconfSession);
  76         // Premature streams are allowed (meaning listener can register even if no provider is available yet)
  77         if(notifications.isStreamAvailable(streamNameType) == false) {
  78             LOG.warn("Registering premature stream {}. No publisher available yet for session {}", streamNameType, getNetconfSessionIdForReporting());
  79         }
  80
  81         final NotificationListenerRegistration notificationListenerRegistration =
  82                 notifications.registerNotificationListener(streamNameType, new NotificationSubscription(netconfSession, filter));
  83         subscriptions.add(notificationListenerRegistration);
  84
  85         return XmlUtil.createElement(document, XmlNetconfConstants.OK, Optional.<String>absent());
  86     }
  87
  88     private static StreamNameType parseStreamIfPresent(final XmlElement operationElement) throws DocumentedException {
  89         final Optional<XmlElement> stream = operationElement.getOnlyChildElementWithSameNamespaceOptionally("stream");
  90         return stream.isPresent() ? new StreamNameType(stream.get().getTextContent()) : NetconfNotificationManager.BASE_STREAM_NAME;
  91     }
  92
  93     @Override
  94     protected String getOperationName() {
  95         return CREATE_SUBSCRIPTION;
  96     }
  97
  98     @Override
  99     protected String getOperationNamespace() {
 100         return CreateSubscriptionInput.QNAME.getNamespace().toString();
 101     }
 102
 103     @Override
 104     public void setSession(final NetconfSession session) {
 105         this.netconfSession = session;
 106     }
 107
 108     @Override
 109     public void close() {
 110         netconfSession = null;
 111         // Unregister from notification streams
 112         for (final NotificationListenerRegistration subscription : subscriptions) {
 113             subscription.close();
 114         }
 115     }
 116
 117     private static class NotificationSubscription implements NetconfNotificationListener {
 118         private final NetconfSession currentSession;
 119         private final Optional<XmlElement> filter;
 120
 121         public NotificationSubscription(final NetconfSession currentSession, final Optional<XmlElement> filter) {
 122             this.currentSession = currentSession;
 123             this.filter = filter;
 124         }
 125
 126         @Override
 127         public void onNotification(final StreamNameType stream, final NetconfNotification notification) {
 128             if (filter.isPresent()) {
 129                 try {
 130                     final Optional<Document> filtered = SubtreeFilter.applySubtreeNotificationFilter(this.filter.get(), notification.getDocument());
 131                     if (filtered.isPresent()) {
 132                         final Date eventTime = notification.getEventTime();
 133                         currentSession.sendMessage(new NetconfNotification(filtered.get(), eventTime));
 134                     }
 135                 } catch (DocumentedException e) {
 136                     LOG.warn(e.toString());
 137                     currentSession.sendMessage(notification);
 138                 }
 139             } else {
 140                 currentSession.sendMessage(notification);
 141             }
 142         }
 143     }
 144 }