| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.drill.exec.rpc; |
| |
| import io.netty.buffer.ByteBuf; |
| import io.netty.buffer.ByteBufInputStream; |
| import io.netty.channel.ChannelHandlerContext; |
| import io.netty.handler.codec.CorruptedFrameException; |
| import io.netty.handler.codec.MessageToMessageDecoder; |
| |
| import java.io.IOException; |
| import java.util.List; |
| import java.util.concurrent.atomic.AtomicLong; |
| |
| import org.apache.drill.exec.proto.GeneralRPCProtos.RpcHeader; |
| |
| /** |
| * Converts a previously length adjusted buffer into an RpcMessage. |
| */ |
| class RpcDecoder extends MessageToMessageDecoder<ByteBuf> { |
| final org.slf4j.Logger logger; |
| |
| private final AtomicLong messageCounter = new AtomicLong(); |
| |
| public RpcDecoder(String name) { |
| this.logger = org.slf4j.LoggerFactory.getLogger(RpcDecoder.class.getCanonicalName() + "-" + name); |
| } |
| |
| |
| @Override |
| protected void decode(ChannelHandlerContext ctx, ByteBuf buffer, List<Object> out) throws Exception { |
| if (!ctx.channel().isOpen()) { |
| return; |
| } |
| |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug("Inbound rpc message received."); |
| } |
| |
| // now, we know the entire message is in the buffer and the buffer is constrained to this message. Additionally, |
| // this process should avoid reading beyond the end of this buffer so we inform the ByteBufInputStream to throw an |
| // exception if be go beyond readable bytes (as opposed to blocking). |
| final ByteBufInputStream is = new ByteBufInputStream(buffer, buffer.readableBytes()); |
| |
| // read the rpc header, saved in delimited format. |
| checkTag(is, RpcEncoder.HEADER_TAG); |
| final RpcHeader header = RpcHeader.parseDelimitedFrom(is); |
| |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug(" post header read index {}", buffer.readerIndex()); |
| } |
| |
| // read the protobuf body into a buffer. |
| checkTag(is, RpcEncoder.PROTOBUF_BODY_TAG); |
| final int pBodyLength = readRawVarint32(is); |
| final ByteBuf pBody = buffer.slice(buffer.readerIndex(), pBodyLength); |
| buffer.skipBytes(pBodyLength); |
| pBody.retain(1); |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug("Read protobuf body of length {} into buffer {}.", pBodyLength, pBody); |
| } |
| |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug("post protobufbody read index {}", buffer.readerIndex()); |
| } |
| |
| ByteBuf dBody = null; |
| int dBodyLength = 0; |
| |
| // read the data body. |
| if (buffer.readableBytes() > 0) { |
| |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug("Reading raw body, buffer has {} bytes available, is available {}.", buffer.readableBytes(), is.available()); |
| } |
| checkTag(is, RpcEncoder.RAW_BODY_TAG); |
| dBodyLength = readRawVarint32(is); |
| if (buffer.readableBytes() != dBodyLength) { |
| throw new CorruptedFrameException(String.format("Expected to receive a raw body of %d bytes but received a buffer with %d bytes.", dBodyLength, buffer.readableBytes())); |
| } |
| dBody = buffer.slice(); |
| dBody.retain(1); |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug("Read raw body of {}", dBody); |
| } |
| |
| }else{ |
| if (RpcConstants.EXTRA_DEBUGGING) { |
| logger.debug("No need to read raw body, no readable bytes left."); |
| } |
| } |
| |
| |
| // return the rpc message. |
| InboundRpcMessage m = new InboundRpcMessage(header.getMode(), header.getRpcType(), header.getCoordinationId(), |
| pBody, dBody); |
| |
| // move the reader index forward so the next rpc call won't try to work with it. |
| buffer.skipBytes(dBodyLength); |
| messageCounter.incrementAndGet(); |
| if (RpcConstants.SOME_DEBUGGING) { |
| logger.debug("Inbound Rpc Message Decoded {}.", m); |
| } |
| out.add(m); |
| |
| } |
| |
| private void checkTag(ByteBufInputStream is, int expectedTag) throws IOException { |
| int actualTag = readRawVarint32(is); |
| if (actualTag != expectedTag) { |
| throw new CorruptedFrameException(String.format("Expected to read a tag of %d but actually received a value of %d. Happened after reading %d message.", expectedTag, actualTag, messageCounter.get())); |
| } |
| } |
| |
| // Taken from CodedInputStream and modified to enable ByteBufInterface. |
| public static int readRawVarint32(ByteBufInputStream is) throws IOException { |
| byte tmp = is.readByte(); |
| if (tmp >= 0) { |
| return tmp; |
| } |
| int result = tmp & 0x7f; |
| if ((tmp = is.readByte()) >= 0) { |
| result |= tmp << 7; |
| } else { |
| result |= (tmp & 0x7f) << 7; |
| if ((tmp = is.readByte()) >= 0) { |
| result |= tmp << 14; |
| } else { |
| result |= (tmp & 0x7f) << 14; |
| if ((tmp = is.readByte()) >= 0) { |
| result |= tmp << 21; |
| } else { |
| result |= (tmp & 0x7f) << 21; |
| result |= (tmp = is.readByte()) << 28; |
| if (tmp < 0) { |
| // Discard upper 32 bits. |
| for (int i = 0; i < 5; i++) { |
| if (is.readByte() >= 0) { |
| return result; |
| } |
| } |
| throw new CorruptedFrameException("Encountered a malformed varint."); |
| } |
| } |
| } |
| } |
| return result; |
| } |
| |
| } |