BUG-2599 Netconf notification manager initial API and Impl

[controller.git] / opendaylight / netconf / netconf-notifications-impl / src / main / java / org / opendaylight / controller / netconf / notifications / impl / ops / CreateSubscription.java

diff --git a/opendaylight/netconf/netconf-notifications-impl/src/main/java/org/opendaylight/controller/netconf/notifications/impl/ops/CreateSubscription.java b/opendaylight/netconf/netconf-notifications-impl/src/main/java/org/opendaylight/controller/netconf/notifications/impl/ops/CreateSubscription.java
new file mode 100644 (file)
index 0000000..e8b7413
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+++ b/opendaylight/netconf/netconf-notifications-impl/src/main/java/org/opendaylight/controller/netconf/notifications/impl/ops/CreateSubscription.java
@@ -0,0 +1,128 @@
+/*
+ * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.opendaylight.controller.netconf.notifications.impl.ops;
+
+import com.google.common.base.Optional;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.Lists;
+import java.util.List;
+import org.opendaylight.controller.netconf.api.NetconfDocumentedException;
+import org.opendaylight.controller.netconf.api.NetconfSession;
+import org.opendaylight.controller.netconf.api.xml.XmlNetconfConstants;
+import org.opendaylight.controller.netconf.mapping.api.SessionAwareNetconfOperation;
+import org.opendaylight.controller.netconf.notifications.NetconfNotification;
+import org.opendaylight.controller.netconf.notifications.NetconfNotificationListener;
+import org.opendaylight.controller.netconf.notifications.NetconfNotificationRegistry;
+import org.opendaylight.controller.netconf.notifications.NotificationListenerRegistration;
+import org.opendaylight.controller.netconf.notifications.impl.NetconfNotificationManager;
+import org.opendaylight.controller.netconf.util.mapping.AbstractLastNetconfOperation;
+import org.opendaylight.controller.netconf.util.xml.XmlElement;
+import org.opendaylight.controller.netconf.util.xml.XmlUtil;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.CreateSubscriptionInput;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.StreamNameType;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.w3c.dom.Document;
+import org.w3c.dom.Element;
+
+/**
+ * Create subscription listens for create subscription requests and registers notification listeners into notification registry.
+ * Received notifications are sent to the client right away
+ */
+public class CreateSubscription extends AbstractLastNetconfOperation implements SessionAwareNetconfOperation, AutoCloseable {
+
+    private static final Logger LOG = LoggerFactory.getLogger(CreateSubscription.class);
+
+    static final String CREATE_SUBSCRIPTION = "create-subscription";
+
+    private final NetconfNotificationRegistry notifications;
+    private final List<NotificationListenerRegistration> subscriptions = Lists.newArrayList();
+    private NetconfSession netconfSession;
+
+    public CreateSubscription(final String netconfSessionIdForReporting, final NetconfNotificationRegistry notifications) {
+        super(netconfSessionIdForReporting);
+        this.notifications = notifications;
+    }
+
+    @Override
+    protected Element handleWithNoSubsequentOperations(final Document document, final XmlElement operationElement) throws NetconfDocumentedException {
+        operationElement.checkName(CREATE_SUBSCRIPTION);
+        operationElement.checkNamespace(CreateSubscriptionInput.QNAME.getNamespace().toString());
+        // FIXME reimplement using CODEC_REGISTRY and parse everything into generated class instance
+        // Waiting ofr https://git.opendaylight.org/gerrit/#/c/13763/
+
+        // FIXME filter could be supported same way as netconf server filters get and get-config results
+        final Optional<XmlElement> filter = operationElement.getOnlyChildElementWithSameNamespaceOptionally("filter");
+        Preconditions.checkArgument(filter.isPresent() == false, "Filter element not yet supported");
+
+        // Replay not supported
+        final Optional<XmlElement> startTime = operationElement.getOnlyChildElementWithSameNamespaceOptionally("startTime");
+        Preconditions.checkArgument(startTime.isPresent() == false, "StartTime element not yet supported");
+
+        // Stop time not supported
+        final Optional<XmlElement> stopTime = operationElement.getOnlyChildElementWithSameNamespaceOptionally("stopTime");
+        Preconditions.checkArgument(stopTime.isPresent() == false, "StopTime element not yet supported");
+
+        final StreamNameType streamNameType = parseStreamIfPresent(operationElement);
+
+        Preconditions.checkNotNull(netconfSession);
+        // Premature streams are allowed (meaning listener can register even if no provider is available yet)
+        if(notifications.isStreamAvailable(streamNameType) == false) {
+            LOG.warn("Registering premature stream {}. No publisher available yet for session {}", streamNameType, getNetconfSessionIdForReporting());
+        }
+
+        final NotificationListenerRegistration notificationListenerRegistration =
+                notifications.registerNotificationListener(streamNameType, new NotificationSubscription(netconfSession));
+        subscriptions.add(notificationListenerRegistration);
+
+        return XmlUtil.createElement(document, XmlNetconfConstants.OK, Optional.<String>absent());
+    }
+
+    private StreamNameType parseStreamIfPresent(final XmlElement operationElement) throws NetconfDocumentedException {
+        final Optional<XmlElement> stream = operationElement.getOnlyChildElementWithSameNamespaceOptionally("stream");
+        return stream.isPresent() ? new StreamNameType(stream.get().getTextContent()) : NetconfNotificationManager.BASE_STREAM_NAME;
+    }
+
+    @Override
+    protected String getOperationName() {
+        return CREATE_SUBSCRIPTION;
+    }
+
+    @Override
+    protected String getOperationNamespace() {
+        return CreateSubscriptionInput.QNAME.getNamespace().toString();
+    }
+
+    @Override
+    public void setSession(final NetconfSession session) {
+        this.netconfSession = session;
+    }
+
+    @Override
+    public void close() {
+        netconfSession = null;
+        // Unregister from notification streams
+        for (final NotificationListenerRegistration subscription : subscriptions) {
+            subscription.close();
+        }
+    }
+
+    private static class NotificationSubscription implements NetconfNotificationListener {
+        private final NetconfSession currentSession;
+
+        public NotificationSubscription(final NetconfSession currentSession) {
+            this.currentSession = currentSession;
+        }
+
+        @Override
+        public void onNotification(final StreamNameType stream, final NetconfNotification notification) {
+            currentSession.sendMessage(notification);
+        }
+    }
+}