如何从 Java websocket 服务器访问客户端主机名、http headers 等?

How to access client hostname, http headers etc from a Java websocket server?

我已经学习了许多教程和示例示例代码,但我还没有看到像我们在 Servlet 请求 object 中那样访问客户端的 HTTP header、主机名等的方法。

我该怎么做?

假设我将 onOpen 定义为-

@OnOpen
    public void onOpen(Session session) {

} 

在上述方法中,有没有一种方法可以使用 session 字段访问底层 HTTP 连接详细信息?即使我可以访问底层 Servlet(如果有的话)我也可以

参见第 4.1.1.5 章 Tyrus user guide. It requires some amount of work to get the info from ServerEnpointConfig.Configurator to endpoint instance, but it can be done. (see ModifyRequestResponseHeadersTest.java)

基于link1link2

我终于想通了我们可以通过以下两个类获取客户​​端IP,实际上您可以使用暴露的httpservletRequest做更多的事情...

ServletAwareConfigurator .java

package examples;
import java.lang.reflect.Field;

import javax.servlet.http.HttpServletRequest;

import javax.websocket.HandshakeResponse;
import javax.websocket.server.HandshakeRequest;
import javax.websocket.server.ServerEndpointConfig;
import javax.websocket.server.ServerEndpointConfig.Configurator;

public class ServletAwareConfigurator extends ServerEndpointConfig.Configurator {

    @Override
    public void modifyHandshake(ServerEndpointConfig config, HandshakeRequest request, HandshakeResponse response) {
        HttpServletRequest httpservletRequest = getField(request, HttpServletRequest.class);
        String sClientIP = httpservletRequest.getRemoteAddr();
        config.getUserProperties().put("clientip", sClientIP);
        // ...
    }

    //hacking reflector to expose fields...
    private static < I, F > F getField(I instance, Class < F > fieldType) {
        try {
            for (Class < ? > type = instance.getClass(); type != Object.class; type = type.getSuperclass()) {
                for (Field field: type.getDeclaredFields()) {
                    if (fieldType.isAssignableFrom(field.getType())) {
                        field.setAccessible(true);
                        return (F) field.get(instance);
                    }
                }
            }
        } catch (Exception e) {
            // Handle?
        }
        return null;
    }
}

GetHttpSessionSocket.java

package examples;
import java.io.IOException;
import javax.servlet.http.HttpSession;
import javax.websocket.EndpointConfig;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;

@ServerEndpoint(value = "/example",
    configurator = ServletAwareConfigurator.class)
public class GetHttpSessionSocket {
    private Session wsSession;
    private String sClientIP;

    @OnOpen
    public void open(Session session, EndpointConfig config) {
        this.wsSession = session;
        this.sClientIP = (String) config.getUserProperties()
            .get("clientip");
    }
    @OnMessage
    public void echo(String msg) throws IOException {
        wsSession.getBasicRemote().sendText(msg);
    }
}