replicate/mdsal-replicate-netty/src/main/java/org/opendaylight/mdsal/replicate/netty/SourceSingletonService.java

   1 /*
   2  * Copyright (c) 2020 PANTHEON.tech, s.r.o. 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.mdsal.replicate.netty;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.util.concurrent.Futures;
  13 import com.google.common.util.concurrent.ListenableFuture;
  14 import com.google.common.util.concurrent.MoreExecutors;
  15 import com.google.common.util.concurrent.SettableFuture;
  16 import io.netty.channel.Channel;
  17 import io.netty.channel.ChannelFuture;
  18 import io.netty.channel.ChannelInitializer;
  19 import io.netty.channel.ChannelOption;
  20 import io.netty.channel.socket.SocketChannel;
  21 import io.netty.handler.timeout.IdleStateHandler;
  22 import java.time.Duration;
  23 import java.util.ArrayList;
  24 import java.util.Collection;
  25 import java.util.HashSet;
  26 import java.util.List;
  27 import java.util.concurrent.TimeUnit;
  28 import org.checkerframework.checker.lock.qual.GuardedBy;
  29 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeService;
  30 import org.opendaylight.mdsal.singleton.common.api.ClusterSingletonService;
  31 import org.opendaylight.mdsal.singleton.common.api.ServiceGroupIdentifier;
  32 import org.opendaylight.yangtools.yang.data.codec.binfmt.NormalizedNodeStreamVersion;
  33 import org.slf4j.Logger;
  34 import org.slf4j.LoggerFactory;
  35
  36 /**
  37  * Cluster Singleton Service handler for delta stream source. Responsible for starting/stopping the delta stream source
  38  * for a particular port.
  39  */
  40 final class SourceSingletonService extends ChannelInitializer<SocketChannel> implements ClusterSingletonService {
  41     private static final Logger LOG = LoggerFactory.getLogger(SourceSingletonService.class);
  42     private static final ServiceGroupIdentifier SGID =
  43             ServiceGroupIdentifier.create(SourceSingletonService.class.getName());
  44
  45     private final BootstrapSupport bootstrapSupport;
  46     private final DOMDataTreeChangeService dtcs;
  47     private final int listenPort;
  48
  49     @GuardedBy("this")
  50     private final Collection<SocketChannel> children = new HashSet<>();
  51     private final Duration keepaliveInterval;
  52     private final int maxMissedKeepalives;
  53     @GuardedBy("this")
  54     private Channel serverChannel;
  55
  56     SourceSingletonService(final BootstrapSupport bootstrapSupport, final DOMDataTreeChangeService dtcs,
  57             final int listenPort, final Duration keepaliveInterval, final int maxMissedKeepalives) {
  58         this.bootstrapSupport = requireNonNull(bootstrapSupport);
  59         this.dtcs = requireNonNull(dtcs);
  60         this.listenPort = listenPort;
  61         this.keepaliveInterval = requireNonNull(keepaliveInterval);
  62         this.maxMissedKeepalives = maxMissedKeepalives;
  63         LOG.info("Replication source on port {} waiting for cluster-wide mastership", listenPort);
  64     }
  65
  66     @Override
  67     public ServiceGroupIdentifier getIdentifier() {
  68         return SGID;
  69     }
  70
  71     @Override
  72     public synchronized void instantiateServiceInstance() {
  73         final ChannelFuture future = bootstrapSupport.newServerBootstrap()
  74                 .option(ChannelOption.SO_BACKLOG, 3)
  75                 .childOption(ChannelOption.SO_KEEPALIVE, true)
  76                 .childHandler(this)
  77                 .bind(listenPort);
  78
  79         try {
  80             future.sync();
  81         } catch (InterruptedException e) {
  82             throw new IllegalStateException("Failed to bind port " + listenPort, e);
  83         }
  84
  85         serverChannel = future.channel();
  86         LOG.info("Replication source started on port {}", listenPort);
  87     }
  88
  89     @Override
  90     public synchronized ListenableFuture<?> closeServiceInstance() {
  91         LOG.info("Replication source on port {} shutting down", listenPort);
  92
  93         final List<ListenableFuture<Void>> futures = new ArrayList<>();
  94
  95         // Close server channel
  96         futures.add(closeChannel(serverChannel));
  97         serverChannel = null;
  98
  99         // Close all child channels
 100         for (SocketChannel channel : children) {
 101             futures.add(closeChannel(channel));
 102         }
 103         children.clear();
 104
 105         final ListenableFuture<?> ret = Futures.nonCancellationPropagating(Futures.successfulAsList(futures));
 106         ret.addListener(() -> {
 107             LOG.info("Replication source on port {} shut down", listenPort);
 108         }, MoreExecutors.directExecutor());
 109         return ret;
 110     }
 111
 112     @Override
 113     public synchronized void initChannel(final SocketChannel ch) {
 114         if (serverChannel == null) {
 115             LOG.debug("Channel {} established while shutting down, closing it", ch);
 116             ch.close();
 117             return;
 118         }
 119
 120         ch.pipeline()
 121             .addLast("frameDecoder", new MessageFrameDecoder())
 122             .addLast("idleStateHandler", new IdleStateHandler(0, keepaliveInterval.toNanos(), 0, TimeUnit.NANOSECONDS))
 123             .addLast("keepaliveHandler", new SourceKeepaliveHandler(maxMissedKeepalives))
 124             .addLast("requestHandler", new SourceRequestHandler(dtcs))
 125             // Output, in reverse order
 126             .addLast("frameEncoder", MessageFrameEncoder.INSTANCE)
 127             .addLast("dtclHandler", new DeltaEncoder(NormalizedNodeStreamVersion.current()));
 128         children.add(ch);
 129
 130         LOG.info("Channel {} established", ch);
 131     }
 132
 133     private static ListenableFuture<Void> closeChannel(final Channel ch) {
 134         final SettableFuture<Void> ret = SettableFuture.create();
 135         ch.closeFuture().addListener(chf -> {
 136             final Throwable cause = chf.cause();
 137             if (cause != null) {
 138                 ret.setException(cause);
 139             } else {
 140                 ret.set(null);
 141             }
 142         });
 143
 144         ch.close();
 145         return ret;
 146     }
 147 }