java - Netty:如何将查询字符串与 websocket 一起使用？

Question

这是我的ChannelInitializer#initChannel的代码片段

    ChannelPipeline p = ch.pipeline();

    p.addLast(new HttpServerCodec()         
    .addLast(new HttpObjectAggregator(65536))
    .addLast( new LoggingHandler(LogLevel.INFO))
    .addLast(new WebSocketServerProtocolHandler("/chat"))
    .addLast(new TextWebSocketFrameToChatMessageDecoder())
    .addLast(new UserAccessHandler())

它可以通过ws://mydomain/chat接受，现在我想解析这样的查询字符串ws://mydomain/chat?accesskey=hello >

我已经查找了WebSocketServerProtocolHandler，但我找不到如何获取查询字符串。

如何获取(或解析)查询字符串？感谢您的帮助。

Answer 1

重写方法:userEventTriggered 并处理事件 HandshakeComplete。

参见WebSocketServerProtocolHandshakeHandler

Netty 4.1

public class TextWebSocketFrameToChatMessageDecoder extends SimpleChannelInboundHandler<WebSocketFrame> {
    public final static AttributeKey<Map<String,String>> RequestParams = AttributeKey.valueOf("request.params");

    @Override
    public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
        if(evt instanceof HandshakeComplete){
            HandshakeComplete handshake = (HandshakeComplete)evt;

            //http request header
            HttpHeaders headers = handshake.requestHeaders();

            //http request uri: /chat?accesskey=hello
            String              uri    = handshake.requestUri(); 

            //TODO: parse uri parameters to map ...
            Map<String, String> params ;

            //put to channel context
            ctx.channel().attr(RequestParams).set(params);

        }else{
            ctx.fireUserEventTriggered(evt);
        }
    }

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, WebSocketFrame frame) throws Exception {
        //on message
        if (frame instanceof TextWebSocketFrame) {
            Map<String, String> params    = ctx.channel().attr(RequestParams).get();
            String              accesskey = params.get("accesskey");
            System.out.println( accesskey ); //hello
        } else {
            System.out.println( "Unsupported frame type: " + frame.getClass().getName() );
        }        
    }
}