org.springframework.web.socket.sockjs.transport.session.StreamingSockJsSession Maven / Gradle / Ivy
/*
* Copyright 2002-2015 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 org.springframework.web.socket.sockjs.transport.session;
import java.io.IOException;
import java.util.Map;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.util.Assert;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.sockjs.SockJsTransportFailureException;
import org.springframework.web.socket.sockjs.frame.SockJsFrame;
import org.springframework.web.socket.sockjs.frame.SockJsMessageCodec;
import org.springframework.web.socket.sockjs.transport.SockJsServiceConfig;
/**
* A SockJS session for use with streaming HTTP transports.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public abstract class StreamingSockJsSession extends AbstractHttpSockJsSession {
private int byteCount;
public StreamingSockJsSession(String sessionId, SockJsServiceConfig config,
WebSocketHandler wsHandler, Map attributes) {
super(sessionId, config, wsHandler, attributes);
}
/**
* @deprecated as of 4.2, since this method is no longer used.
*/
@Override
@Deprecated
protected boolean isStreaming() {
return true;
}
/**
* Get the prelude to write to the response before any other data.
* @since 4.2
*/
protected abstract byte[] getPrelude(ServerHttpRequest request);
@Override
protected void handleRequestInternal(ServerHttpRequest request, ServerHttpResponse response,
boolean initialRequest) throws IOException {
byte[] prelude = getPrelude(request);
Assert.notNull(prelude);
response.getBody().write(prelude);
response.flush();
if (initialRequest) {
writeFrame(SockJsFrame.openFrame());
}
flushCache();
}
@Override
protected void flushCache() throws SockJsTransportFailureException {
while (!getMessageCache().isEmpty()) {
String message = getMessageCache().poll();
SockJsMessageCodec messageCodec = getSockJsServiceConfig().getMessageCodec();
SockJsFrame frame = SockJsFrame.messageFrame(messageCodec, message);
writeFrame(frame);
this.byteCount += (frame.getContentBytes().length + 1);
if (logger.isTraceEnabled()) {
logger.trace(this.byteCount + " bytes written so far, " +
getMessageCache().size() + " more messages not flushed");
}
if (this.byteCount >= getSockJsServiceConfig().getStreamBytesLimit()) {
logger.trace("Streamed bytes limit reached, recycling current request");
resetRequest();
this.byteCount = 0;
break;
}
}
scheduleHeartbeat();
}
}