Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 1 | package org.onlab.netty; |
| 2 | |
Madan Jampani | 86ed055 | 2014-10-03 16:45:42 -0700 | [diff] [blame] | 3 | import static com.google.common.base.Preconditions.checkState; |
| 4 | import io.netty.buffer.ByteBuf; |
| 5 | import io.netty.channel.ChannelHandlerContext; |
| 6 | import io.netty.handler.codec.ReplayingDecoder; |
| 7 | |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 8 | import java.util.Arrays; |
| 9 | import java.util.List; |
| 10 | |
Madan Jampani | 29e5dfd | 2014-10-07 17:26:25 -0700 | [diff] [blame^] | 11 | import org.slf4j.Logger; |
| 12 | import org.slf4j.LoggerFactory; |
| 13 | |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 14 | /** |
| 15 | * Decoder for inbound messages. |
| 16 | */ |
| 17 | public class MessageDecoder extends ReplayingDecoder<DecoderState> { |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 18 | |
Madan Jampani | 29e5dfd | 2014-10-07 17:26:25 -0700 | [diff] [blame^] | 19 | private final Logger log = LoggerFactory.getLogger(getClass()); |
| 20 | |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 21 | private final NettyMessagingService messagingService; |
Madan Jampani | 53e44e6 | 2014-10-07 12:39:51 -0700 | [diff] [blame] | 22 | |
| 23 | private static final KryoSerializer SERIALIZER = new KryoSerializer(); |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 24 | |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 25 | private int contentLength; |
| 26 | |
Madan Jampani | 53e44e6 | 2014-10-07 12:39:51 -0700 | [diff] [blame] | 27 | public MessageDecoder(NettyMessagingService messagingService) { |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 28 | super(DecoderState.READ_HEADER_VERSION); |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 29 | this.messagingService = messagingService; |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 30 | } |
| 31 | |
| 32 | @Override |
Madan Jampani | 86ed055 | 2014-10-03 16:45:42 -0700 | [diff] [blame] | 33 | protected void decode( |
| 34 | ChannelHandlerContext context, |
| 35 | ByteBuf buffer, |
| 36 | List<Object> out) throws Exception { |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 37 | |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 38 | switch(state()) { |
| 39 | case READ_HEADER_VERSION: |
| 40 | int headerVersion = buffer.readInt(); |
| 41 | checkState(headerVersion == MessageEncoder.HEADER_VERSION, "Unexpected header version"); |
| 42 | checkpoint(DecoderState.READ_PREAMBLE); |
| 43 | case READ_PREAMBLE: |
| 44 | byte[] preamble = new byte[MessageEncoder.PREAMBLE.length]; |
| 45 | buffer.readBytes(preamble); |
| 46 | checkState(Arrays.equals(MessageEncoder.PREAMBLE, preamble), "Message has wrong preamble"); |
| 47 | checkpoint(DecoderState.READ_CONTENT_LENGTH); |
| 48 | case READ_CONTENT_LENGTH: |
| 49 | contentLength = buffer.readInt(); |
| 50 | checkpoint(DecoderState.READ_SERIALIZER_VERSION); |
| 51 | case READ_SERIALIZER_VERSION: |
| 52 | int serializerVersion = buffer.readInt(); |
| 53 | checkState(serializerVersion == MessageEncoder.SERIALIZER_VERSION, "Unexpected serializer version"); |
| 54 | checkpoint(DecoderState.READ_CONTENT); |
| 55 | case READ_CONTENT: |
Madan Jampani | 53e44e6 | 2014-10-07 12:39:51 -0700 | [diff] [blame] | 56 | InternalMessage message = SERIALIZER.decode(buffer.readBytes(contentLength).nioBuffer()); |
Madan Jampani | 938aa43 | 2014-10-04 17:37:23 -0700 | [diff] [blame] | 57 | message.setMessagingService(messagingService); |
| 58 | out.add(message); |
| 59 | checkpoint(DecoderState.READ_HEADER_VERSION); |
| 60 | break; |
| 61 | default: |
| 62 | checkState(false, "Must not be here"); |
| 63 | } |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 64 | } |
Madan Jampani | 29e5dfd | 2014-10-07 17:26:25 -0700 | [diff] [blame^] | 65 | |
| 66 | @Override |
| 67 | public void exceptionCaught(ChannelHandlerContext context, Throwable cause) { |
| 68 | log.error("Exception inside channel handling pipeline.", cause); |
| 69 | context.close(); |
| 70 | } |
Madan Jampani | ab6d311 | 2014-10-02 16:30:14 -0700 | [diff] [blame] | 71 | } |