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 static com.google.common.base.Preconditions.checkState;
  12
  13 import org.opendaylight.controller.netconf.api.NetconfDocumentedException;
  14 import org.opendaylight.controller.netconf.api.NetconfMessage;
  15 import org.opendaylight.controller.netconf.api.NetconfSession;
  16 import org.opendaylight.controller.netconf.api.NetconfTerminationReason;
  17 import org.opendaylight.controller.netconf.impl.osgi.NetconfOperationRouterImpl;
  18 import org.opendaylight.controller.netconf.util.messages.SendErrorExceptionUtil;
  19 import org.opendaylight.controller.netconf.util.xml.XmlElement;
  20 import org.opendaylight.controller.netconf.util.xml.XmlNetconfConstants;
  21 import org.opendaylight.controller.netconf.util.xml.XmlUtil;
  22 import org.opendaylight.protocol.framework.SessionListener;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25 import org.w3c.dom.Document;
  26 import org.w3c.dom.Node;
  27
  28 import com.google.common.base.Preconditions;
  29 import com.google.common.collect.ImmutableMap;
  30
  31 public class NetconfServerSessionListener implements
  32         SessionListener<NetconfMessage, NetconfServerSession, NetconfTerminationReason> {
  33
  34     static final Logger logger = LoggerFactory.getLogger(NetconfServerSessionListener.class);
  35     public static final String MESSAGE_ID = "message-id";
  36
  37     private NetconfOperationRouterImpl operationRouter;
  38
  39     public NetconfServerSessionListener(NetconfOperationRouterImpl operationRouter) {
  40         this.operationRouter = operationRouter;
  41     }
  42
  43     @Override
  44     public void onSessionUp(NetconfServerSession netconfNetconfServerSession) {
  45
  46     }
  47
  48     @Override
  49     public void onSessionDown(NetconfServerSession netconfNetconfServerSession, Exception e) {
  50         logger.debug("Session {} down, reason: {}", netconfNetconfServerSession, e.getMessage());
  51
  52         operationRouter.close();
  53     }
  54
  55     @Override
  56     public void onSessionTerminated(NetconfServerSession netconfNetconfServerSession,
  57             NetconfTerminationReason netconfTerminationReason) {
  58         logger.debug("Session {} terminated, reason: {}", netconfNetconfServerSession,
  59                 netconfTerminationReason.getErrorMessage());
  60
  61         operationRouter.close();
  62     }
  63
  64     @Override
  65     public void onMessage(NetconfServerSession session, NetconfMessage netconfMessage) {
  66         try {
  67
  68             Preconditions.checkState(operationRouter != null, "Cannot handle message, session up was not yet received");
  69             // FIXME: there is no validation since the document may contain yang
  70             // schemas
  71             final NetconfMessage message = processDocument(netconfMessage,
  72                     session);
  73             logger.debug("Respondign with message {}", XmlUtil.toString(message.getDocument()));
  74             session.sendMessage(message);
  75
  76             if (isCloseSession(netconfMessage)) {
  77                 closeNetconfSession(session);
  78             }
  79
  80         } catch (final RuntimeException e) {
  81             logger.error("Unexpected exception", e);
  82             // TODO: should send generic error or close session?
  83             throw new RuntimeException("Unable to process incoming message " + netconfMessage, e);
  84         } catch (NetconfDocumentedException e) {
  85             SendErrorExceptionUtil.sendErrorMessage(session, e, netconfMessage);
  86         }
  87     }
  88
  89     private void closeNetconfSession(NetconfServerSession session) {
  90         // destroy NetconfOperationService
  91         session.close();
  92         logger.info("Session {} closed successfully", session.getSessionId());
  93     }
  94
  95     private NetconfMessage processDocument(final NetconfMessage netconfMessage,
  96             NetconfSession session) throws NetconfDocumentedException {
  97
  98         final Document incommingDocument = netconfMessage.getDocument();
  99         final Node rootNode = incommingDocument.getDocumentElement();
 100
 101         if (rootNode.getLocalName().equals(XmlNetconfConstants.RPC_KEY)) {
 102             final String messageId = rootNode.getAttributes().getNamedItem(MESSAGE_ID).getTextContent();
 103             checkState(messageId != null);
 104             final Document responseDocument = XmlUtil.newDocument();
 105             Document rpcReply = operationRouter.onNetconfMessage(
 106                     incommingDocument, session);
 107             responseDocument.appendChild(responseDocument.importNode(rpcReply.getDocumentElement(), true));
 108             return new NetconfMessage(responseDocument);
 109         } else {
 110             // unknown command, send RFC 4741 p.70 unknown-element
 111             /*
 112              * Tag: unknown-element Error-type: rpc, protocol, application
 113              * Severity: error Error-info: <bad-element> : name of the
 114              * unexpected element Description: An unexpected element is present.
 115              */
 116             // TODO add message to error info
 117             throw new NetconfDocumentedException("Unknown tag " + rootNode.getNodeName(),
 118                     NetconfDocumentedException.ErrorType.protocol, NetconfDocumentedException.ErrorTag.unknown_element,
 119                     NetconfDocumentedException.ErrorSeverity.error, ImmutableMap.of("bad-element",
 120                             rootNode.getNodeName()));
 121         }
 122     }
 123
 124     private static boolean isCloseSession(final NetconfMessage incommingDocument) {
 125         final Document document = incommingDocument.getDocument();
 126         XmlElement rpcElement = XmlElement.fromDomDocument(document);
 127         if (rpcElement.getOnlyChildElementOptionally("close-session").isPresent())
 128             return true;
 129
 130         return false;
 131     }
 132 }