com.avanza.astrix.netty.client.NettyRemotingClientHandler.java Source code

Introduction

Here is the source code for com.avanza.astrix.netty.client.NettyRemotingClientHandler.java

Source

/*
 * Copyright 2014 Avanza Bank AB
 *
 * 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 com.avanza.astrix.netty.client;

import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import com.avanza.astrix.remoting.client.AstrixServiceInvocationRequest;
import com.avanza.astrix.remoting.client.AstrixServiceInvocationResponse;

import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import rx.Observable;
import rx.Subscriber;

public class NettyRemotingClientHandler extends ChannelInboundHandlerAdapter {

    public static final String NETTY_RESPONSE_SUBSCRIBER_ID = "netty.responseSubscriberId";
    private volatile ChannelHandlerContext ctx;

    private ConcurrentMap<String, Subscriber<? super AstrixServiceInvocationResponse>> subscriberBySubscriberId = new ConcurrentHashMap<>();

    @Override
    public void channelActive(ChannelHandlerContext ctx) {
        this.ctx = ctx;
        //         Send the first message if this handler is a client-side handler.
        //        ctx.writeAndFlush();
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) {
        AstrixServiceInvocationResponse response = (AstrixServiceInvocationResponse) msg;
        String invocationId = response.getHeader(NETTY_RESPONSE_SUBSCRIBER_ID);
        Subscriber<? super AstrixServiceInvocationResponse> subscriber = getSubscriber(invocationId);
        if (subscriber == null) {
            return;
        }
        subscriber.onNext(response);
        subscriber.onCompleted();
        // Echo back the received object to the server.
        //        ctx.write(msg);
    }

    private Subscriber<? super AstrixServiceInvocationResponse> getSubscriber(String invocationId) {
        Subscriber<? super AstrixServiceInvocationResponse> subscriber = this.subscriberBySubscriberId
                .remove(invocationId);
        return subscriber;
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) {
        ctx.flush();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }

    public Observable<AstrixServiceInvocationResponse> sendInvocationRequest(
            AstrixServiceInvocationRequest request) {
        return Observable.create((subscriber) -> {
            String invocationId = UUID.randomUUID().toString();
            this.subscriberBySubscriberId.put(invocationId, subscriber);
            request.setHeader(NETTY_RESPONSE_SUBSCRIBER_ID, invocationId);
            ctx.writeAndFlush(request);
        });
    }
}