org.apache.activemq.artemis.core.server.protocol.websocket.WebSocketFrameEncoder Maven / Gradle / Ivy
/*
* 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.activemq.artemis.core.server.protocol.websocket;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;
import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame;
import io.netty.handler.codec.http.websocketx.ContinuationWebSocketFrame;
/**
* This class uses the maximum frame payload size to packetize/frame outbound websocket messages into
* continuation frames.
*/
public class WebSocketFrameEncoder extends ChannelOutboundHandlerAdapter {
private int maxFramePayloadLength;
/**
* @param maxFramePayloadLength
*/
public WebSocketFrameEncoder(int maxFramePayloadLength) {
this.maxFramePayloadLength = maxFramePayloadLength;
}
@Override
public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {
if (msg instanceof ByteBuf) {
writeContinuationFrame(ctx, (ByteBuf) msg, promise);
} else {
super.write(ctx, msg, promise);
}
}
private void writeContinuationFrame(ChannelHandlerContext ctx, ByteBuf byteBuf, ChannelPromise promise) {
int count = byteBuf.readableBytes();
int length = Math.min(count, maxFramePayloadLength);
boolean finalFragment = length == count;
ByteBuf fragment = Unpooled.buffer(length);
byteBuf.readBytes(fragment, length);
ctx.writeAndFlush(new BinaryWebSocketFrame(finalFragment, 0, fragment), promise);
while ((count = byteBuf.readableBytes()) > 0) {
length = Math.min(count, maxFramePayloadLength);
finalFragment = length == count;
fragment = Unpooled.buffer(length);
byteBuf.readBytes(fragment, length);
ctx.writeAndFlush(new ContinuationWebSocketFrame(finalFragment, 0, fragment), promise);
}
byteBuf.release();
}
}