rxweb.engine.server.netty.NettyServerCodecHandlerAdapter.java Source code

Introduction

Here is the source code for rxweb.engine.server.netty.NettyServerCodecHandlerAdapter.java

Source

/*
 * Copyright 2002-2014 the original author or authors.
 *
 * Licensed 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 rxweb.engine.server.netty;

import java.nio.ByteBuffer;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufHolder;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelDuplexHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.handler.codec.http.*;
import io.netty.util.ReferenceCountUtil;
import rxweb.server.ServerRequest;
import rxweb.support.Assert;

/**
 * Conversion between Netty types ({@link HttpRequest}, {@link HttpResponse}, {@link HttpContent} and {@link LastHttpContent})
 * and Spring RxWeb types ({@link NettyServerResponseAdapter}, {@link NettyServerRequestAdapter} and {@link ByteBuffer}).
 *
 * @author Sebastien Deleuze
 */
public class NettyServerCodecHandlerAdapter extends ChannelDuplexHandler {

    private ServerRequest request;
    private UnicastContentSubject<ByteBuffer> requestContent;

    public NettyServerCodecHandlerAdapter() {
        this.requestContent = UnicastContentSubject.createWithoutNoSubscriptionTimeout();
    }

    /**
     * Create a {@link NettyServerRequestAdapter} when a {@link HttpRequest} is received, and use
     * @ {@link UnicastContentSubject} to send the content as a request stream.
     */
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        Class<?> messageClass = msg.getClass();
        if (HttpRequest.class.isAssignableFrom(messageClass)) {
            this.request = new NettyServerRequestAdapter((HttpRequest) msg, this.requestContent);
            super.channelRead(ctx, this.request);
        } else if (HttpContent.class.isAssignableFrom(messageClass)) {
            Assert.notNull(this.request);
            ByteBuf content = ((ByteBufHolder) msg).content();
            ByteBuffer nioBuffer = content.nioBuffer();
            this.requestContent.onNext(nioBuffer);
            if (LastHttpContent.class.isAssignableFrom(messageClass)) {
                this.requestContent.onCompleted();
            }
            // FIXME I need to make it works without that ...
            super.channelRead(ctx, this.request);
        } else {
            super.channelRead(ctx, msg);
        }
    }

    @Override
    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
        Class<?> messageClass = msg.getClass();

        if (NettyServerResponseAdapter.class.isAssignableFrom(messageClass)) {
            NettyServerResponseAdapter response = (NettyServerResponseAdapter) msg;
            super.write(ctx, response.getNettyResponse(), promise);
        } else if (ByteBuffer.class.isAssignableFrom(messageClass)) {
            ByteBuf byteBuf = Unpooled.copiedBuffer((ByteBuffer) msg);
            super.write(ctx, new DefaultHttpContent(byteBuf), promise);
        } else {
            super.write(ctx, msg, promise); // pass through, since we do not understand this message.
        }

    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        super.channelReadComplete(ctx);
        ctx.pipeline().flush(); // If there is nothing to flush, this is a short-circuit in netty.
    }

}