Micronaut websocket 消息验证

Question

我正在尝试在 WebSocket OnMessage 请求中实现消息验证，该请求通常是如下所示的字符串。

    @OnMessage
    open fun onMessage(
        gameId: String,
        username: String,
        message: String,
        session: WebSocketSession?
    ): Publisher<String> {
        val msg = "[$username] $message"
        return broadcaster.broadcast(msg, isValid(gameId))
    }

我正在使用 Micronaut 的 Bean Validation 将消息验证为 Message 对象，如下所示。

package com.andreasjj.websocket

import com.fasterxml.jackson.databind.exc.MismatchedInputException
import io.micronaut.http.annotation.Error
import io.micronaut.http.codec.CodecException
import io.micronaut.websocket.WebSocketBroadcaster
import io.micronaut.websocket.WebSocketSession
import io.micronaut.websocket.annotation.*
import org.reactivestreams.Publisher
import java.util.function.Predicate
import javax.validation.Valid

@ServerWebSocket("/ws/game/{gameId}/{username}")
open class GameWebsocket(private val broadcaster: WebSocketBroadcaster) {
    @OnOpen
    fun onOpen(gameId: String, username: String, session: WebSocketSession?): Publisher<String> {
        val msg = "Hello [$username]"
        return broadcaster.broadcast(msg, isValid(gameId))
    }

    @OnMessage
    open fun onMessage(
        gameId: String,
        username: String,
        @Valid message: GameClientMessage,
        session: WebSocketSession?
    ): Publisher<String> {
        println(message)
        val msg = "[$username] $message"
        return broadcaster.broadcast(msg, isValid(gameId))
    }

    @OnClose
    fun onClose(
        gameId: String,
        username: String,
        session: WebSocketSession?
    ): Publisher<String> {
        val msg = "Bye [$username]"
        return broadcaster.broadcast(msg, isValid(gameId))
    }

    private fun isValid(gameId: String): Predicate<WebSocketSession> {
        return Predicate { s: WebSocketSession ->
            gameId.equals(
                s.uriVariables.get(
                    "gameId",
                    String::class.java, null
                ), ignoreCase = true
            )
        }
    }
}

@Introspected
data class GameClientMessage(
    @field:NotNull var type: GameClientMessageType,
    @field:NotBlank var text: String
)

enum class GameClientMessageType {
    STARTGAME,
    ENDGAME,
    SKIPROUND,
    NEXTROUND,
    ANSWER
}

这种方法有效，但是当消息不符合验证要求时，它会失败并出现一个丑陋的错误并关闭 WebSocket 连接

backend_1            | 13:59:47.241 [default-nioEventLoopGroup-1-4] ERROR i.m.h.s.n.w.NettyServerWebSocketHandler - Error Processing WebSocket Message [io.micronaut.websocket.context.DefaultWebSocketBeanRegistry$DefaultWebSocketBean@13e15b55]: Error decoding stream for type [class com.andreasjj.websocket.GameClientMessage]: Missing required creator property 'type' (index 0)
backend_1            |  at [Source: (byte[])"{"action":"Message","text":"Hello"}"; line: 1, column: 35]
backend_1            | io.micronaut.http.codec.CodecException: Error decoding stream for type [class com.andreasjj.websocket.GameClientMessage]: Missing required creator property 'type' (index 0)
backend_1            |  at [Source: (byte[])"{"action":"Message","text":"Hello"}"; line: 1, column: 35]
backend_1            |  at io.micronaut.jackson.codec.JacksonMediaTypeCodec.decode(JacksonMediaTypeCodec.java:178)
backend_1            |  at io.micronaut.http.netty.websocket.AbstractNettyWebSocketHandler.lambda$handleWebSocketFrame$4(AbstractNettyWebSocketHandler.java:331)
backend_1            |  at java.base/java.util.Optional.map(Optional.java:265)
backend_1            |  at io.micronaut.http.netty.websocket.AbstractNettyWebSocketHandler.handleWebSocketFrame(AbstractNettyWebSocketHandler.java:331)
backend_1            |  at io.micronaut.http.netty.websocket.AbstractNettyWebSocketHandler.channelRead0(AbstractNettyWebSocketHandler.java:294)
backend_1            |  at io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:99)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
backend_1            |  at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:324)
backend_1            |  at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:296)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
backend_1            |  at io.netty.handler.timeout.IdleStateHandler.channelRead(IdleStateHandler.java:286)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357)
backend_1            |  at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379)
backend_1            |  at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365)
backend_1            |  at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919)
backend_1            |  at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166)
backend_1            |  at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719)
backend_1            |  at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655)
backend_1            |  at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581)
backend_1            |  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
backend_1            |  at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989)
backend_1            |  at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
backend_1            |  at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
backend_1            |  at java.base/java.lang.Thread.run(Thread.java:834)
backend_1            | Caused by: com.fasterxml.jackson.databind.exc.MismatchedInputException: Missing required creator property 'type' (index 0)
backend_1            |  at [Source: (byte[])"{"action":"Message","text":"Hello"}"; line: 1, column: 35]
backend_1            |  at com.fasterxml.jackson.databind.exc.MismatchedInputException.from(MismatchedInputException.java:59)
backend_1            |  at com.fasterxml.jackson.databind.DeserializationContext.reportInputMismatch(DeserializationContext.java:1615)
backend_1            |  at com.fasterxml.jackson.databind.deser.impl.PropertyValueBuffer._findMissing(PropertyValueBuffer.java:194)
backend_1            |  at com.fasterxml.jackson.databind.deser.impl.PropertyValueBuffer.getParameters(PropertyValueBuffer.java:160)
backend_1            |  at com.fasterxml.jackson.databind.deser.ValueInstantiator.createFromObjectWith(ValueInstantiator.java:288)
backend_1            |  at com.fasterxml.jackson.databind.deser.impl.PropertyBasedCreator.build(PropertyBasedCreator.java:202)
backend_1            |  at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:520)
backend_1            |  at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:1390)
backend_1            |  at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:362)
backend_1            |  at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:195)
backend_1            |  at com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:322)
backend_1            |  at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4593)
backend_1            |  at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3609)
backend_1            |  at io.micronaut.jackson.codec.JacksonMediaTypeCodec.decode(JacksonMediaTypeCodec.java:175)
backend_1            |  ... 30 common frames omitted

我尝试添加一个被调用的@OnError 函数，但此时，WebSocket 连接被“异常关闭”关闭，它不是很有用。那么我将如何处理错误/验证而不让整个事情死掉呢？

Answer 1

使用webSocketConnection.onclose=function() {webSocketConnection.open() } 临时修复您的错误。对于托管在 Glitch 上的项目，这也是一种很好的技术。