嵌入式tomcat 8.0.21中的Spring websocket

Question

I want to create a WebSocket based on an example. The only spin is that I'm running my application in embedded tomcat.

package com.test.websocket;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.AbstractWebSocketHandler;

public class WebSocketTest extends AbstractWebSocketHandler {
    private static Logger logger = LoggerFactory.getLogger(WebSocketTest.class);

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        logger.debug("Recieved websocket message: " + message);

        session.sendMessage(new TextMessage("thanks"));
    }

    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        logger.info("WebSocket connection established!");
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
        logger.info("WebSocket connection closed!");
    }
}

Configuration(websocket.spring.xml):

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:websocket="http://www.springframework.org/schema/websocket"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
              http://www.springframework.org/schema/beans/spring-beans.xsd
              http://www.springframework.org/schema/websocket
              http://www.springframework.org/schema/websocket/spring-websocket.xsd">

       <websocket:handlers>
              <websocket:mapping path="/socket" handler="webSocketHandler"/>
       </websocket:handlers>

       <bean id="webSocketHandler" class="com.test.websocket.WebSocketTest"/>
</beans>

Servlet mapping is at /websocket/*

From the log It seems like the spring-websocket is initialized successfully however I'm getting this error, when I try to connect to the websocket.

Servlet.service() for servlet [spring-websocket] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.web.socket.server.HandshakeFailureException: Uncaught failure for request http://localhost:9876/websocket/socket; nested exception is java.lang.IllegalArgumentException: No 'javax.websocket.server.ServerContainer' ServletContext attribute. Are you running in a Servlet container that supports JSR-356?] with root cause

Dependencies are: tomcat-embed-core, tomcat-embed-websocket, tomcat-juli and because of ( Spring websocket example - error - Are you running in a Servlet container that supports J SR-356? ) javax.websocket-api and tomcat-websocket

What am I missing?

Thanks in advance!

Answer 1

Maybe i found a solution to your problem.

You need to use WsSci servlet container initializer to the embedded tomcat context:

context.addServletContainerInitializer(new WsSci(), null);

https://github.com/spring-projects/spring-boot/issues/439