opendaylight/netconf/netconf-impl/src/main/java/org/opendaylight/controller/netconf/impl/NetconfServerSessionListener.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 com.google.common.base.Preconditions;
  12 import com.google.common.collect.ImmutableMap;
  13 import org.opendaylight.controller.netconf.api.NetconfDocumentedException;
  14 import org.opendaylight.controller.netconf.api.NetconfMessage;
  15 import org.opendaylight.controller.netconf.api.NetconfTerminationReason;
  16 import org.opendaylight.controller.netconf.impl.osgi.NetconfOperationRouterImpl;
  17 import org.opendaylight.controller.netconf.util.messages.SendErrorExceptionUtil;
  18 import org.opendaylight.controller.netconf.util.xml.XmlElement;
  19 import org.opendaylight.controller.netconf.util.xml.XmlNetconfConstants;
  20 import org.opendaylight.controller.netconf.util.xml.XmlUtil;
  21 import org.opendaylight.protocol.framework.SessionListener;
  22 import org.slf4j.Logger;
  23 import org.slf4j.LoggerFactory;
  24 import org.w3c.dom.Document;
  25 import org.w3c.dom.Node;
  26
  27 import static com.google.common.base.Preconditions.checkState;
  28
  29 public class NetconfServerSessionListener implements
  30         SessionListener<NetconfMessage, NetconfServerSession, NetconfTerminationReason> {
  31
  32     static final Logger logger = LoggerFactory.getLogger(NetconfServerSessionListener.class);
  33     public static final String MESSAGE_ID = "message-id";
  34
  35     private NetconfOperationRouterImpl operationRouter;
  36
  37     public NetconfServerSessionListener(NetconfOperationRouterImpl operationRouter) {
  38         this.operationRouter = operationRouter;
  39     }
  40
  41     @Override
  42     public void onSessionUp(NetconfServerSession netconfNetconfServerSession) {
  43
  44     }
  45
  46     @Override
  47     public void onSessionDown(NetconfServerSession netconfNetconfServerSession, Exception e) {
  48         logger.debug("Session {} down, reason: {}", netconfNetconfServerSession, e.getMessage());
  49
  50         operationRouter.close();
  51     }
  52
  53     @Override
  54     public void onSessionTerminated(NetconfServerSession netconfNetconfServerSession,
  55             NetconfTerminationReason netconfTerminationReason) {
  56         logger.debug("Session {} terminated, reason: {}", netconfNetconfServerSession,
  57                 netconfTerminationReason.getErrorMessage());
  58
  59         operationRouter.close();
  60     }
  61
  62     @Override
  63     public void onMessage(NetconfServerSession session, NetconfMessage netconfMessage) {
  64         try {
  65
  66             Preconditions.checkState(operationRouter != null, "Cannot handle message, session up was not yet received");
  67             // FIXME: there is no validation since the document may contain yang
  68             // schemas
  69             final NetconfMessage message = processDocument(netconfMessage);
  70             logger.debug("Respondign with message {}", XmlUtil.toString(message.getDocument()));
  71             session.sendMessage(message);
  72
  73             if (isCloseSession(netconfMessage)) {
  74                 closeNetconfSession(session);
  75             }
  76
  77         } catch (final RuntimeException e) {
  78             logger.error("Unexpected exception", e);
  79             // TODO: should send generic error or close session?
  80             throw new RuntimeException("Unable to process incoming message " + netconfMessage, e);
  81         } catch (NetconfDocumentedException e) {
  82             SendErrorExceptionUtil.sendErrorMessage(session, e, netconfMessage);
  83         }
  84     }
  85
  86     private void closeNetconfSession(NetconfServerSession session) {
  87         // destroy NetconfOperationService
  88         session.close();
  89         logger.info("Session {} closed successfully", session.getSessionId());
  90     }
  91
  92     private NetconfMessage processDocument(final NetconfMessage netconfMessage) throws NetconfDocumentedException {
  93
  94         final Document incommingDocument = netconfMessage.getDocument();
  95         final Node rootNode = incommingDocument.getDocumentElement();
  96
  97         if (rootNode.getNodeName().equals(XmlNetconfConstants.RPC_KEY)) {
  98             final String messageId = rootNode.getAttributes().getNamedItem(MESSAGE_ID).getTextContent();
  99             checkState(messageId != null);
 100             final Document responseDocument = XmlUtil.newDocument();
 101             Document rpcReply = operationRouter.onNetconfMessage(incommingDocument);
 102             responseDocument.appendChild(responseDocument.importNode(rpcReply.getDocumentElement(), true));
 103             return new NetconfMessage(responseDocument);
 104         } else {
 105             // unknown command, send RFC 4741 p.70 unknown-element
 106             /*
 107              * Tag: unknown-element Error-type: rpc, protocol, application
 108              * Severity: error Error-info: <bad-element> : name of the
 109              * unexpected element Description: An unexpected element is present.
 110              */
 111             // TODO add message to error info
 112             throw new NetconfDocumentedException("Unknown tag " + rootNode.getNodeName(),
 113                     NetconfDocumentedException.ErrorType.protocol, NetconfDocumentedException.ErrorTag.unknown_element,
 114                     NetconfDocumentedException.ErrorSeverity.error, ImmutableMap.of("bad-element",
 115                             rootNode.getNodeName()));
 116         }
 117     }
 118
 119     private static boolean isCloseSession(final NetconfMessage incommingDocument) {
 120         final Document document = incommingDocument.getDocument();
 121         XmlElement rpcElement = XmlElement.fromDomDocument(document);
 122         if (rpcElement.getOnlyChildElementOptionally("close-session").isPresent())
 123             return true;
 124
 125         return false;
 126     }
 127 }