org.apache.hadoop.hdfs.server.datanode.web.PortUnificationServerHandler.java Source code

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Here is the source code for org.apache.hadoop.hdfs.server.datanode.web.PortUnificationServerHandler.java

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/**
 * 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.hadoop.hdfs.server.datanode.web;

import java.net.InetSocketAddress;
import java.util.List;

import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hdfs.server.datanode.web.dtp.DtpHttp2Handler;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http2.Http2CodecUtil;
import io.netty.handler.stream.ChunkedWriteHandler;

/**
 * A port unification handler to support HTTP/1.1 and HTTP/2 on the same port.
 */
@InterfaceAudience.Private
public class PortUnificationServerHandler extends ByteToMessageDecoder {

    private static final ByteBuf HTTP2_CLIENT_CONNECTION_PREFACE = Http2CodecUtil.connectionPrefaceBuf();

    // we only want to support HTTP/1.1 and HTTP/2, so the first 3 bytes is
    // enough. No HTTP/1.1 request could start with "PRI"
    private static final int MAGIC_HEADER_LENGTH = 3;

    private final InetSocketAddress proxyHost;

    private final Configuration conf;

    private final Configuration confForCreate;

    public PortUnificationServerHandler(InetSocketAddress proxyHost, Configuration conf,
            Configuration confForCreate) {
        this.proxyHost = proxyHost;
        this.conf = conf;
        this.confForCreate = confForCreate;
    }

    private void configureHttp1(ChannelHandlerContext ctx) {
        ctx.pipeline().addLast(new HttpServerCodec(), new ChunkedWriteHandler(),
                new URLDispatcher(proxyHost, conf, confForCreate));
    }

    private void configureHttp2(ChannelHandlerContext ctx) {
        ctx.pipeline().addLast(new DtpHttp2Handler());
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
        if (in.readableBytes() < MAGIC_HEADER_LENGTH) {
            return;
        }
        if (ByteBufUtil.equals(in, 0, HTTP2_CLIENT_CONNECTION_PREFACE, 0, MAGIC_HEADER_LENGTH)) {
            configureHttp2(ctx);
        } else {
            configureHttp1(ctx);
        }
        ctx.pipeline().remove(this);
    }

}