opendaylight/netconf/netconf-impl/src/main/java/org/opendaylight/controller/netconf/impl/NetconfServerSessionNegotiatorFactory.java

   1 /*
   2  * Copyright (c) 2013 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.controller.netconf.impl;
  10
  11 import io.netty.channel.Channel;
  12 import io.netty.util.Timer;
  13 import io.netty.util.concurrent.Promise;
  14
  15 import java.io.InputStream;
  16
  17 import javax.xml.xpath.XPathConstants;
  18 import javax.xml.xpath.XPathExpression;
  19
  20 import org.opendaylight.controller.netconf.api.NetconfMessage;
  21 import org.opendaylight.controller.netconf.api.NetconfServerSessionPreferences;
  22 import org.opendaylight.controller.netconf.impl.mapping.CapabilityProvider;
  23 import org.opendaylight.controller.netconf.impl.osgi.NetconfOperationServiceFactoryListener;
  24 import org.opendaylight.controller.netconf.util.NetconfUtil;
  25 import org.opendaylight.controller.netconf.util.xml.XMLNetconfUtil;
  26 import org.opendaylight.controller.netconf.util.xml.XmlNetconfConstants;
  27 import org.opendaylight.controller.netconf.util.xml.XmlUtil;
  28 import org.opendaylight.protocol.framework.SessionListenerFactory;
  29 import org.opendaylight.protocol.framework.SessionNegotiator;
  30 import org.opendaylight.protocol.framework.SessionNegotiatorFactory;
  31 import org.w3c.dom.Document;
  32 import org.w3c.dom.Element;
  33 import org.w3c.dom.Node;
  34
  35 import com.google.common.base.Preconditions;
  36
  37 public class NetconfServerSessionNegotiatorFactory implements SessionNegotiatorFactory<NetconfMessage, NetconfServerSession, NetconfServerSessionListener> {
  38
  39     public static final String SERVER_HELLO_XML_LOCATION = "/server_hello.xml";
  40
  41     private final Timer timer;
  42
  43     private static final Document helloMessageTemplate = loadHelloMessageTemplate();
  44     private final SessionIdProvider idProvider;
  45     private final NetconfOperationServiceFactoryListener factoriesListener;
  46     private final long connectionTimeoutMillis;
  47
  48     public NetconfServerSessionNegotiatorFactory(Timer timer, NetconfOperationServiceFactoryListener factoriesListener,
  49             SessionIdProvider idProvider, long connectionTimeoutMillis) {
  50         this.timer = timer;
  51         this.factoriesListener = factoriesListener;
  52         this.idProvider = idProvider;
  53         this.connectionTimeoutMillis = connectionTimeoutMillis;
  54     }
  55
  56     private static Document loadHelloMessageTemplate() {
  57         InputStream resourceAsStream = NetconfServerSessionNegotiatorFactory.class
  58                 .getResourceAsStream(SERVER_HELLO_XML_LOCATION);
  59         Preconditions.checkNotNull(resourceAsStream, "Unable to load server hello message blueprint from %s",
  60                 SERVER_HELLO_XML_LOCATION);
  61         return NetconfUtil.createMessage(resourceAsStream).getDocument();
  62     }
  63
  64     @Override
  65     public SessionNegotiator<NetconfServerSession> getSessionNegotiator(SessionListenerFactory<NetconfServerSessionListener> sessionListenerFactory, Channel channel,
  66             Promise<NetconfServerSession> promise) {
  67         long sessionId = idProvider.getNextSessionId();
  68
  69         NetconfServerSessionPreferences proposal = new NetconfServerSessionPreferences(createHelloMessage(sessionId),
  70                 sessionId);
  71         return new NetconfServerSessionNegotiator(proposal, promise, channel, timer,
  72                 sessionListenerFactory.getSessionListener(), connectionTimeoutMillis);
  73     }
  74
  75     private static final XPathExpression sessionIdXPath = XMLNetconfUtil
  76             .compileXPath("/netconf:hello/netconf:session-id");
  77     private static final XPathExpression capabilitiesXPath = XMLNetconfUtil
  78             .compileXPath("/netconf:hello/netconf:capabilities");
  79
  80     private NetconfMessage createHelloMessage(long sessionId) {
  81         Document helloMessageTemplate = getHelloTemplateClone();
  82
  83         // change session ID
  84         final Node sessionIdNode = (Node) XmlUtil.evaluateXPath(sessionIdXPath, helloMessageTemplate,
  85                 XPathConstants.NODE);
  86         sessionIdNode.setTextContent(String.valueOf(sessionId));
  87
  88         // add capabilities from yang store
  89         final Element capabilitiesElement = (Element) XmlUtil.evaluateXPath(capabilitiesXPath, helloMessageTemplate,
  90                 XPathConstants.NODE);
  91
  92         CapabilityProvider capabilityProvider = new CapabilityProviderImpl(factoriesListener.getSnapshot(sessionId));
  93
  94         for (String capability : capabilityProvider.getCapabilities()) {
  95             final Element capabilityElement = helloMessageTemplate.createElement(XmlNetconfConstants.CAPABILITY);
  96             capabilityElement.setTextContent(capability);
  97             capabilitiesElement.appendChild(capabilityElement);
  98         }
  99         return new NetconfMessage(helloMessageTemplate);
 100     }
 101
 102     private synchronized Document getHelloTemplateClone() {
 103         return (Document) helloMessageTemplate.cloneNode(true);
 104     }
 105 }