RedisDecoder.java — netty Source File

Source Code

/*
 * Copyright 2016 The Netty Project
 *
 * The Netty Project 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:
 *
 * https://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 io.netty.handler.codec.redis;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.util.ByteProcessor;
import io.netty.util.CharsetUtil;
import io.netty.util.internal.UnstableApi;

import java.util.List;

/**
 * Decodes the Redis protocol into {@link RedisMessage} objects following
 * <a href="https://redis.io/topics/protocol">RESP (REdis Serialization Protocol)</a>.
 *
 * {@link RedisMessage} parts can be aggregated to {@link RedisMessage} using
 * {@link RedisArrayAggregator} or processed directly.
 */
@UnstableApi
public final class RedisDecoder extends ByteToMessageDecoder {

    private final ToPositiveLongProcessor toPositiveLongProcessor = new ToPositiveLongProcessor();

    private final boolean decodeInlineCommands;
    private final int maxInlineMessageLength;
    private final RedisMessagePool messagePool;

    // current decoding states
    private State state = State.DECODE_TYPE;
    private RedisMessageType type;
    private int remainingBulkLength;

    private enum State {
        DECODE_TYPE,
        DECODE_INLINE, // SIMPLE_STRING, ERROR, INTEGER
        DECODE_LENGTH, // BULK_STRING, ARRAY_HEADER
        DECODE_BULK_STRING_EOL,
        DECODE_BULK_STRING_CONTENT,
    }

    /**
     * Creates a new instance with default {@code maxInlineMessageLength} and {@code messagePool}
     * and inline command decoding disabled.
     */
    public RedisDecoder() {
// ... (273 more lines)