2 * Copyright (c) 2020 PANTHEON.tech, s.r.o. and others. All rights reserved.
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
8 package org.opendaylight.mdsal.replicate.netty;
10 import static com.google.common.base.Verify.verify;
11 import static java.util.Objects.requireNonNull;
13 import io.netty.buffer.ByteBuf;
14 import io.netty.buffer.ByteBufInputStream;
15 import io.netty.channel.Channel;
16 import io.netty.channel.ChannelHandlerContext;
17 import io.netty.channel.SimpleChannelInboundHandler;
18 import java.io.IOException;
19 import java.util.List;
20 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
21 import org.opendaylight.mdsal.dom.api.ClusteredDOMDataTreeChangeListener;
22 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeService;
23 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
24 import org.opendaylight.yangtools.concepts.Registration;
25 import org.opendaylight.yangtools.yang.data.codec.binfmt.NormalizedNodeDataInput;
26 import org.opendaylight.yangtools.yang.data.tree.api.DataTreeCandidate;
27 import org.slf4j.Logger;
28 import org.slf4j.LoggerFactory;
31 * Final inbound handler on source side. Handles requests coming from sink and reacts to them.
33 final class SourceRequestHandler extends SimpleChannelInboundHandler<ByteBuf> {
34 private static final Logger LOG = LoggerFactory.getLogger(SourceRequestHandler.class);
36 private final DOMDataTreeChangeService dtcs;
38 private Registration reg;
40 SourceRequestHandler(final DOMDataTreeChangeService dtcs) {
41 this.dtcs = requireNonNull(dtcs);
45 public void channelInactive(final ChannelHandlerContext ctx) {
46 LOG.info("Channel {} going inactive", ctx.channel());
51 ctx.fireChannelInactive();
55 protected void channelRead0(final ChannelHandlerContext ctx, final ByteBuf msg) throws IOException {
56 verify(msg.isReadable(), "Empty message received");
58 final short msgType = msg.readUnsignedByte();
59 final Channel channel = ctx.channel();
60 LOG.trace("Channel {} received message type {}", channel, msgType);
62 case Constants.MSG_SUBSCRIBE_REQ -> subscribe(channel, msg);
63 case Constants.MSG_PONG -> {
66 default -> throw new IllegalStateException("Unexpected message type " + msgType);
71 public void exceptionCaught(final ChannelHandlerContext ctx, final Throwable cause) {
72 LOG.warn("Closing channel {} due to an error", ctx.channel(), cause);
76 private void subscribe(final Channel channel, final ByteBuf msg) throws IOException {
77 verify(reg == null, "Unexpected subscription when already subscribed");
79 final DOMDataTreeIdentifier dataTree;
80 try (var input = new ByteBufInputStream(msg)) {
81 final var normalizedInput = NormalizedNodeDataInput.newDataInput(input);
83 dataTree = new DOMDataTreeIdentifier(LogicalDatastoreType.readFrom(normalizedInput),
84 normalizedInput.readYangInstanceIdentifier());
87 LOG.info("Channel {} subscribing to {}", channel, dataTree);
88 reg = dtcs.registerDataTreeChangeListener(dataTree, new ClusteredDOMDataTreeChangeListener() {
90 public void onInitialData() {
91 LOG.debug("Channel {} tree {} has empty data", channel, dataTree);
92 channel.writeAndFlush(AbstractSourceMessage.empty());
96 public void onDataTreeChanged(final List<DataTreeCandidate> changes) {
97 LOG.debug("Channel {} tree {} has {} changes", channel, dataTree, changes.size());
98 channel.writeAndFlush(AbstractSourceMessage.of(changes));