如何在websocket打开方法中获取当前用户的id

Question

我试图在websocket的打开方法中获得用户id，为此我使用shiro，但我得到主题为空，这是我的方法:

@OnOpen
public void open(final Session session, @PathParam("room") final String room) {
    Subject currentUser = SecurityUtils.getSubject();
    long id = currentUser.getPrincipals().oneByType(model.Users.class)
            .getId();
    log.info("session openend and bound to room: " + room);
    session.getUserProperties().put("user", id);
}

有谁知道我该怎么做吗?

Answer 1

一天后我解决了这个问题，我把open方法的类改成了:

@ServerEndpoint(value = "/chat/{room}", configurator = GetHttpSessionConfigurator.class, encoders = ChatMessageEncoder.class, decoders = ChatMessageDecoder.class) 
public class ChatEndpoint {
private final Logger log = Logger.getLogger(getClass().getName());
@OnOpen
public void open(final Session session,
        @PathParam("room") final String room, EndpointConfig config) {
    log.info("session openend and bound to room: " + room);
    Principal userPrincipal = (Principal) config.getUserProperties().get(
            "UserPrincipal");
    String user=null;
    try {
         user = (String) userPrincipal.getName();
    } catch (Exception e) {
        e.printStackTrace();
    }
    session.getUserProperties().put("user", user);
    System.out.println("!!!!!!!! "+user);
}}

和GetHttpSessionConfigurator类:

public class GetHttpSessionConfigurator extends
    ServerEndpointConfig.Configurator {

@Override
public void modifyHandshake(ServerEndpointConfig config,
        HandshakeRequest request, HandshakeResponse response) {
    config.getUserProperties().put("UserPrincipal",request.getUserPrincipal());
    config.getUserProperties().put("userInRole", request.isUserInRole("someRole"));  
}}

从Principal中实现我的用户模型并重写getName()方法来获取id:

@Override
public String getName() {
    String id=Long.toString(getId());
    return id;
}

Answer 2

一个更简单的解决方案是使用javax.websocket.Session.getUserPrincipal()，其中返回此会话的已认证用户，如果没有用户为此会话进行身份验证，则返回null

@OnOpen
public void open(final Session session, @PathParam("room") final String room) {
    Principal userPrincipal = session.getUserPrincipal();
    if (userPrincipal == null) {
        log.info("The user is not logged in.");
    } else {
        String user = userPrincipal.getName();
        // now that your have your user here, your can do whatever other operation you want.
    }
}

后续的方法如onMessage也可以使用相同的方法来检索用户