opendaylight/netconf/netconf-client/src/main/java/org/opendaylight/controller/netconf/client/NetconfClientSessionNegotiator.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.client;
  10
  11 import com.google.common.base.Function;
  12 import com.google.common.collect.Collections2;
  13 import io.netty.channel.Channel;
  14 import io.netty.util.Timer;
  15 import io.netty.util.concurrent.Promise;
  16 import org.opendaylight.controller.netconf.api.NetconfMessage;
  17 import org.opendaylight.controller.netconf.api.NetconfSessionPreferences;
  18 import org.opendaylight.controller.netconf.util.AbstractNetconfSessionNegotiator;
  19 import org.opendaylight.controller.netconf.util.xml.XMLNetconfUtil;
  20 import org.opendaylight.controller.netconf.util.xml.XmlElement;
  21 import org.opendaylight.controller.netconf.util.xml.XmlNetconfConstants;
  22 import org.opendaylight.controller.netconf.util.xml.XmlUtil;
  23 import org.opendaylight.protocol.framework.SessionListener;
  24 import org.w3c.dom.Document;
  25 import org.w3c.dom.Node;
  26
  27 import javax.annotation.Nullable;
  28 import javax.xml.xpath.XPathConstants;
  29 import javax.xml.xpath.XPathExpression;
  30 import java.util.Collection;
  31 import java.util.List;
  32
  33 public class NetconfClientSessionNegotiator extends
  34         AbstractNetconfSessionNegotiator<NetconfSessionPreferences, NetconfClientSession> {
  35
  36     protected NetconfClientSessionNegotiator(NetconfSessionPreferences sessionPreferences,
  37             Promise<NetconfClientSession> promise, Channel channel, Timer timer, SessionListener sessionListener,
  38             long connectionTimeoutMillis) {
  39         super(sessionPreferences, promise, channel, timer, sessionListener, connectionTimeoutMillis);
  40     }
  41
  42     private static Collection<String> getCapabilities(Document doc) {
  43         XmlElement responseElement = XmlElement.fromDomDocument(doc);
  44         XmlElement capabilitiesElement = responseElement
  45                 .getOnlyChildElementWithSameNamespace(XmlNetconfConstants.CAPABILITIES);
  46         List<XmlElement> caps = capabilitiesElement.getChildElements(XmlNetconfConstants.CAPABILITY);
  47         return Collections2.transform(caps, new Function<XmlElement, String>() {
  48
  49             @Nullable
  50             @Override
  51             public String apply(@Nullable XmlElement input) {
  52                 // Trim possible leading/tailing whitespace
  53                 return input.getTextContent().trim();
  54             }
  55         });
  56     }
  57
  58     private static final XPathExpression sessionIdXPath = XMLNetconfUtil
  59             .compileXPath("/netconf:hello/netconf:session-id");
  60
  61     private long extractSessionId(Document doc) {
  62         final Node sessionIdNode = (Node) XmlUtil.evaluateXPath(sessionIdXPath, doc, XPathConstants.NODE);
  63         String textContent = sessionIdNode.getTextContent();
  64         if (textContent == null || textContent.equals("")) {
  65             throw new IllegalStateException("Session id not received from server");
  66         }
  67
  68         return Long.valueOf(textContent);
  69     }
  70
  71     @Override
  72     protected NetconfClientSession getSession(SessionListener sessionListener, Channel channel, NetconfMessage message) {
  73         return new NetconfClientSession(sessionListener, channel, extractSessionId(message.getDocument()),
  74                 getCapabilities(message.getDocument()));
  75     }
  76 }