protocol/netconf-server/src/main/java/org/opendaylight/netconf/server/SendErrorExceptionUtil.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 package org.opendaylight.netconf.server;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import io.netty.channel.Channel;
  13 import io.netty.channel.ChannelFuture;
  14 import io.netty.channel.ChannelFutureListener;
  15 import javax.xml.XMLConstants;
  16 import org.opendaylight.netconf.api.DocumentedException;
  17 import org.opendaylight.netconf.api.NamespaceURN;
  18 import org.opendaylight.netconf.api.NetconfSession;
  19 import org.opendaylight.netconf.api.messages.NetconfMessage;
  20 import org.opendaylight.netconf.api.messages.RpcMessage;
  21 import org.opendaylight.netconf.api.messages.RpcReplyMessage;
  22 import org.opendaylight.netconf.api.xml.XmlUtil;
  23 import org.slf4j.Logger;
  24 import org.slf4j.LoggerFactory;
  25 import org.w3c.dom.Attr;
  26 import org.w3c.dom.Document;
  27
  28 final class SendErrorExceptionUtil {
  29     private static final Logger LOG = LoggerFactory.getLogger(SendErrorExceptionUtil.class);
  30
  31     private SendErrorExceptionUtil() {
  32         // Hidden on purpose
  33     }
  34
  35     static void sendErrorMessage(final NetconfSession session, final DocumentedException sendErrorException) {
  36         LOG.trace("Sending error", sendErrorException);
  37         final Document errorDocument = createDocument(sendErrorException);
  38         ChannelFuture channelFuture = session.sendMessage(new NetconfMessage(errorDocument));
  39         channelFuture.addListener(new SendErrorVerifyingListener(sendErrorException));
  40     }
  41
  42     static void sendErrorMessage(final Channel channel, final DocumentedException sendErrorException) {
  43         LOG.trace("Sending error", sendErrorException);
  44         final Document errorDocument = createDocument(sendErrorException);
  45         ChannelFuture channelFuture = channel.writeAndFlush(new NetconfMessage(errorDocument));
  46         channelFuture.addListener(new SendErrorVerifyingListener(sendErrorException));
  47     }
  48
  49     static void sendErrorMessage(final NetconfSession session, final DocumentedException sendErrorException,
  50             final NetconfMessage incommingMessage) {
  51         final Document errorDocument = createDocument(sendErrorException);
  52         if (LOG.isTraceEnabled()) {
  53             LOG.trace("Sending error {}", XmlUtil.toString(errorDocument));
  54         }
  55
  56         tryToCopyAttributes(incommingMessage.getDocument(), errorDocument, sendErrorException);
  57         ChannelFuture channelFuture = session.sendMessage(new NetconfMessage(errorDocument));
  58         channelFuture.addListener(new SendErrorVerifyingListener(sendErrorException));
  59     }
  60
  61     // FIXME: this should be handled through RpcMessage.toReply(DocumentedException)
  62     @SuppressWarnings("checkstyle:IllegalCatch")
  63     private static void tryToCopyAttributes(final Document incommingDocument, final Document errorDocument,
  64             final DocumentedException sendErrorException) {
  65         try {
  66             final var incommingRpc = incommingDocument.getDocumentElement();
  67             checkState(RpcMessage.ELEMENT_NAME.equals(incommingRpc.getLocalName())
  68                 && NamespaceURN.BASE.equals(incommingRpc.getNamespaceURI()), "Missing %s element",
  69                 RpcMessage.ELEMENT_NAME);
  70
  71             final var rpcReply = errorDocument.getDocumentElement();
  72             checkState(rpcReply.getTagName().equals(RpcReplyMessage.ELEMENT_NAME), "Missing %s element",
  73                 RpcReplyMessage.ELEMENT_NAME);
  74
  75             final var incomingAttributes = incommingRpc.getAttributes();
  76             for (int i = 0; i < incomingAttributes.getLength(); i++) {
  77                 final var attr = (Attr) incomingAttributes.item(i);
  78                 // skip namespace
  79                 if (attr.getNodeName().equals(XMLConstants.XMLNS_ATTRIBUTE)) {
  80                     continue;
  81                 }
  82                 rpcReply.setAttributeNode((Attr) errorDocument.importNode(attr, true));
  83             }
  84         } catch (final Exception e) {
  85             LOG.warn("Unable to copy incomming attributes to {}, returned rpc-error might be invalid for client",
  86                     sendErrorException, e);
  87         }
  88     }
  89
  90     private static Document createDocument(final DocumentedException sendErrorException) {
  91         return sendErrorException.toXMLDocument();
  92     }
  93
  94     /**
  95      * Checks if netconf error was sent successfully.
  96      */
  97     private static final class SendErrorVerifyingListener implements ChannelFutureListener {
  98         private final DocumentedException sendErrorException;
  99
 100         SendErrorVerifyingListener(final DocumentedException sendErrorException) {
 101             this.sendErrorException = sendErrorException;
 102         }
 103
 104         @Override
 105         public void operationComplete(final ChannelFuture channelFuture) {
 106             final var cause = channelFuture.cause();
 107             if (cause != null) {
 108                 throw new IllegalStateException("Unable to send exception " + sendErrorException, cause);
 109             }
 110         }
 111     }
 112 }