websocket - 码头 9 WebSocketListener，beforeConnect

Question

WebSocketListener 可以提供 beforeWebSocketConnect 方法吗？

我想在打开套接字之前检查请求参数是否正确，如果不正确则拒绝连接。

但是，有没有办法取消协议切换？

Answer 1

从 Jetty 9 开始，您可以使用WebSocketCreator概念来实现此行为。

package org.eclipse.jetty.websocket.server.examples;

import java.io.IOException;

import org.eclipse.jetty.websocket.api.UpgradeRequest;
import org.eclipse.jetty.websocket.api.UpgradeResponse;
import org.eclipse.jetty.websocket.server.examples.echo.BigEchoSocket;
import org.eclipse.jetty.websocket.servlet.WebSocketCreator;
import org.eclipse.jetty.websocket.servlet.WebSocketServlet;
import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;

@SuppressWarnings("serial")
public class MyCustomCreationServlet extends WebSocketServlet
{
    public static class MyCustomCreator implements WebSocketCreator
    {
        @Override
        public Object createWebSocket(UpgradeRequest req, UpgradeResponse resp)
        {
            String query = req.getQueryString();

            // Start looking at the UpgradeRequest to determine what you want to do
            if ((query == null) || (query.length() <= 0))
            {
                try
                {
                    // Let UPGRADE request for websocket fail with
                    // status code 403 (FORBIDDEN) [per RFC-6455]
                    resp.sendForbidden("Unspecified query");
                }
                catch (IOException e)
                {
                    // An input or output exception occurs
                    e.printStackTrace();
                }

                // No UPGRADE
                return null;
            }

            // Create the websocket we want to
            if (query.contains("bigecho"))
            {
                return new BigEchoSocket();
            }
            else if (query.contains("echo"))
            {
                return new MyEchoSocket();
            }

            // Let UPGRADE fail with 503 (UNAVAILABLE)
            return null;
        }
    }

    @Override
    public void configure(WebSocketServletFactory factory)
    {
        factory.setCreator(new MyCustomCreator());
    }
}