/*
* Copyright 2014 Netflix, Inc.
*
* 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 io.reactivex.netty.protocol.http.websocket;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.ChannelPromise;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.websocketx.WebSocketClientHandshaker;
import io.netty.handler.codec.http.websocketx.WebSocketFrameAggregator;
import io.netty.handler.codec.http.websocketx.WebSocketFrameDecoder;
import io.netty.handler.codec.http.websocketx.WebSocketFrameEncoder;
import io.netty.handler.codec.http.websocketx.WebSocketHandshakeException;
import io.reactivex.netty.client.ClientMetricsEvent;
import io.reactivex.netty.metrics.Clock;
import io.reactivex.netty.metrics.MetricEventsSubject;
import io.reactivex.netty.protocol.http.websocket.WebSocketClientMetricsHandlers.ClientReadMetricsHandler;
import io.reactivex.netty.protocol.http.websocket.WebSocketClientMetricsHandlers.ClientWriteMetricsHandler;
/**
* {@link WebSocketClientHandler} orchestrates WebSocket handshake process and reconfigures
* pipeline after the handshake is complete.
*
* @author Tomasz Bak
*/
public class WebSocketClientHandler extends ChannelInboundHandlerAdapter {
private final WebSocketClientHandshaker handshaker;
private final int maxFramePayloadLength;
private final boolean messageAggregation;
private final MetricEventsSubject<ClientMetricsEvent<?>> eventsSubject;
private ChannelPromise handshakeFuture;
private long handshakeStartTime;
public WebSocketClientHandler(WebSocketClientHandshaker handshaker,
int maxFramePayloadLength,
boolean messageAggregation,
MetricEventsSubject<ClientMetricsEvent<?>> eventsSubject) {
this.handshaker = handshaker;
this.maxFramePayloadLength = maxFramePayloadLength;
this.messageAggregation = messageAggregation;
this.eventsSubject = eventsSubject;
}
public void addHandshakeFinishedListener(ChannelFutureListener listener) {
handshakeFuture.addListener(listener);
}
@Override
public void handlerAdded(ChannelHandlerContext ctx) {
handshakeFuture = ctx.newPromise();
}
@Override
public void channelActive(ChannelHandlerContext ctx) {
handshakeStartTime = Clock.newStartTimeMillis();
eventsSubject.onEvent(WebSocketClientMetricsEvent.HANDSHAKE_START);
handshaker.handshake(ctx.channel());
}
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
Channel ch = ctx.channel();
if (!handshaker.isHandshakeComplete()) {
finishHandshake(ctx, (FullHttpResponse) msg, ch);
} else {
ctx.fireChannelRead(msg);
}
}
private void finishHandshake(ChannelHandlerContext ctx, FullHttpResponse msg, Channel ch) {
try {
handshaker.finishHandshake(ch, msg);
} catch (WebSocketHandshakeException e) {
eventsSubject.onEvent(WebSocketClientMetricsEvent.HANDSHAKE_FAILURE, Clock.onEndMillis(handshakeStartTime));
handshakeFuture.setFailure(e);
ctx.close();
return;
}
eventsSubject.onEvent(WebSocketClientMetricsEvent.HANDSHAKE_SUCCESS, Clock.onEndMillis(handshakeStartTime));
ChannelPipeline p = ctx.pipeline();
ChannelHandlerContext nettyDecoderCtx = p.context(WebSocketFrameDecoder.class);
p.addAfter(nettyDecoderCtx.name(), "websocket-read-metrics", new ClientReadMetricsHandler(eventsSubject));
ChannelHandlerContext nettyEncoderCtx = p.context(WebSocketFrameEncoder.class);
p.addAfter(nettyEncoderCtx.name(), "websocket-write-metrics", new ClientWriteMetricsHandler(eventsSubject));
if (messageAggregation) {
p.addAfter("websocket-read-metrics", "websocket-frame-aggregator", new WebSocketFrameAggregator(maxFramePayloadLength));
}
p.remove(HttpObjectAggregator.class);
p.remove(this);
handshakeFuture.setSuccess();
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
if (!handshakeFuture.isDone()) {
handshakeFuture.setFailure(cause);
}
ctx.close();
}
}