001/*
002 * Copyright 2002-2019 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.socket.sockjs.transport.handler;
018
019import java.nio.charset.StandardCharsets;
020import java.util.Map;
021
022import org.springframework.http.MediaType;
023import org.springframework.http.server.ServerHttpRequest;
024import org.springframework.web.socket.WebSocketHandler;
025import org.springframework.web.socket.sockjs.frame.DefaultSockJsFrameFormat;
026import org.springframework.web.socket.sockjs.frame.SockJsFrameFormat;
027import org.springframework.web.socket.sockjs.transport.SockJsSession;
028import org.springframework.web.socket.sockjs.transport.TransportHandler;
029import org.springframework.web.socket.sockjs.transport.TransportType;
030import org.springframework.web.socket.sockjs.transport.session.PollingSockJsSession;
031
032/**
033 * A {@link TransportHandler} based on XHR (long) polling.
034 *
035 * @author Rossen Stoyanchev
036 * @since 4.0
037 */
038public class XhrPollingTransportHandler extends AbstractHttpSendingTransportHandler {
039
040        @Override
041        public TransportType getTransportType() {
042                return TransportType.XHR;
043        }
044
045        @Override
046        protected MediaType getContentType() {
047                return new MediaType("application", "javascript", StandardCharsets.UTF_8);
048        }
049
050        @Override
051        protected SockJsFrameFormat getFrameFormat(ServerHttpRequest request) {
052                return new DefaultSockJsFrameFormat("%s\n");
053        }
054
055        @Override
056        public boolean checkSessionType(SockJsSession session) {
057                return (session instanceof PollingSockJsSession);
058        }
059
060        @Override
061        public PollingSockJsSession createSession(
062                        String sessionId, WebSocketHandler handler, Map<String, Object> attributes) {
063
064                return new PollingSockJsSession(sessionId, getServiceConfig(), handler, attributes);
065        }
066
067}