/*
* Copyright 2002-2014 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.handler;
import java.io.IOException;
import java.util.Arrays;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
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.SockJsException;
import org.springframework.web.socket.sockjs.transport.SockJsSession;
import org.springframework.web.socket.sockjs.transport.session.AbstractHttpSockJsSession;
/**
* Base class for HTTP transport handlers that receive messages via HTTP POST.
*
* @author Rossen Stoyanchev
* @since 4.0
*/
public abstract class AbstractHttpReceivingTransportHandler extends AbstractTransportHandler {
@Override
public final void handleRequest(ServerHttpRequest request, ServerHttpResponse response,
WebSocketHandler wsHandler, SockJsSession wsSession) throws SockJsException {
Assert.notNull(wsSession, "No session");
AbstractHttpSockJsSession sockJsSession = (AbstractHttpSockJsSession) wsSession;
handleRequestInternal(request, response, wsHandler, sockJsSession);
}
protected void handleRequestInternal(ServerHttpRequest request, ServerHttpResponse response,
WebSocketHandler wsHandler, AbstractHttpSockJsSession sockJsSession) throws SockJsException {
String[] messages;
try {
messages = readMessages(request);
}
catch (IOException ex) {
logger.error("Failed to read message", ex);
if (ex.getClass().getName().contains("Mapping")) {
// e.g. Jackson's JsonMappingException, indicating an incomplete payload
handleReadError(response, "Payload expected.", sockJsSession.getId());
}
else {
handleReadError(response, "Broken JSON encoding.", sockJsSession.getId());
}
return;
}
catch (Throwable ex) {
logger.error("Failed to read message", ex);
handleReadError(response, "Failed to read message(s)", sockJsSession.getId());
return;
}
if (messages == null) {
handleReadError(response, "Payload expected.", sockJsSession.getId());
return;
}
if (logger.isTraceEnabled()) {
logger.trace("Received message(s): " + Arrays.asList(messages));
}
response.setStatusCode(getResponseStatus());
response.getHeaders().setContentType(new MediaType("text", "plain", UTF8_CHARSET));
sockJsSession.delegateMessages(messages);
}
private void handleReadError(ServerHttpResponse response, String error, String sessionId) {
try {
response.setStatusCode(HttpStatus.INTERNAL_SERVER_ERROR);
response.getBody().write(error.getBytes("UTF-8"));
}
catch (IOException ex) {
throw new SockJsException("Failed to send error: " + error, sessionId, ex);
}
}
protected abstract String[] readMessages(ServerHttpRequest request) throws IOException;
protected abstract HttpStatus getResponseStatus();
}