使用 Spring Websocket 托管 Overflow 默认的WebSocket实现

kagg886

适用于只使用overflow-core开发bot，并且使用spring自带的IoC能力的一套ws解决方案。可以避免早期overflow版本中反向websocket存在的各种问题。

定义handler

class WSHandler : WebSocketHandler, IAdapter {
    override val scope = CoroutineScope(Dispatchers.IO) + SupervisorJob()

    override val logger: Logger = LoggerFactory.getLogger(ActionHandler::class.java)
    override val actionHandler: ActionHandler = ActionHandler(scope.coroutineContext[Job], logger)

    init {
        top.mrxiaom.overflow.internal.Overflow.setup()
        log.info("Youmu WebSocket 已接管默认Overflow Bot Handler,WSBufferSize: ${System.getProperty("org.apache.tomcat.websocket.DEFAULT_BUFFER_SIZE")}")
    }

    override fun afterConnectionEstablished(session: WebSocketSession) {
        //在这里进行鉴权
        scope.launch {
            val botImpl = Bot(
                SpringDelegatedWebSocket(session),
                BotConfig(),
                actionHandler
            )

            val versionInfo = botImpl.getVersionInfo()
            if (botImpl.onebotVersion == 12) {
                session.close(CloseStatus.PROTOCOL_ERROR.withReason("不支持的onebot版本:12"))
                return@launch
            }

            net.mamoe.mirai.Bot.getInstanceOrNull(botImpl.id)?.getOriginChannel()
                ?.close(CloseStatus.NORMAL.withReason("当前连接下线"))

            val bot = with(BotWrapper) {
                val result = runCatching {
                    botImpl.wrap(
                        configuration = BotConfiguration {
                            botLoggerSupplier = {
                                LoggerFactory.getLogger("Bot#${botImpl.id}").asMiraiLogger()
                            }
                            networkLoggerSupplier = {
                                LoggerFactory.getLogger("Net#${botImpl.id}").asMiraiLogger()
                            }
                        }
                    )
                }
                if (result.isFailure) {
                    session.close(CloseStatus.PROTOCOL_ERROR.withReason("无法实例化bot"))
                    return@launch
                }
                result.getOrThrow()
            }
            log.info("Bot ${bot.id} 已连接,协议版本信息:$versionInfo")
            net.mamoe.mirai.Bot._instances[botImpl.id] = bot
        }
    }

    override fun handleMessage(session: WebSocketSession, message: WebSocketMessage<*>) {
        if (message is TextMessage) {
            val text = message.payload
            onReceiveMessage(text)
        }
    }

    override fun handleTransportError(session: WebSocketSession, exception: Throwable) {
    }

    @OptIn(MiraiInternalApi::class)
    override fun afterConnectionClosed(session: WebSocketSession, closeStatus: CloseStatus) {
        val bot = net.mamoe.mirai.Bot.instances.find {
            it.getOriginChannel() == session
        }
        if (bot !== null) {
            bot as BotWrapper
            bot.eventDispatcher.broadcastAsync(BotOfflineEvent.Dropped(bot, cause = RuntimeException("连接断开")))
            net.mamoe.mirai.Bot._instances.remove(bot.id)
            log.info("${bot.id}断开连接")
        }
    }

    override fun supportsPartialMessages(): Boolean = false
}

定义ws session的wrapper。overflow中未使用的方法均可以使用TODO替代。

class SpringDelegatedWebSocket(val delegated: WebSocketSession) : WebSocket {
    override fun close(p0: Int, p1: String?) {
        delegated.close(CloseStatus(p0, p1))
    }

    override fun close(p0: Int) {
        delegated.close(CloseStatus(p0))
    }

    override fun close() {
        delegated.close()
    }

    override fun closeConnection(p0: Int, p1: String?) {
        delegated.close(CloseStatus(p0, p1))
    }

    override fun send(p0: String?) {
        delegated.sendMessage(TextMessage(p0!!))
    }

    override fun send(p0: ByteBuffer?) {
        delegated.sendMessage(BinaryMessage(p0!!))
    }

    override fun send(p0: ByteArray?) {
        delegated.sendMessage(BinaryMessage(p0!!))
    }

    override fun sendFrame(p0: Framedata?) {
        TODO("Not yet implemented")
    }

    override fun sendFrame(p0: MutableCollection<Framedata>?) {
        TODO("Not yet implemented")
    }

    override fun sendPing() {
        delegated.sendMessage(PingMessage())
    }

    override fun sendFragmentedFrame(p0: Opcode?, p1: ByteBuffer?, p2: Boolean) {
        TODO("Not yet implemented")
    }

    override fun hasBufferedData(): Boolean {
        TODO("Not yet implemented")
    }

    override fun getRemoteSocketAddress(): InetSocketAddress = delegated.remoteAddress!!

    override fun getLocalSocketAddress(): InetSocketAddress = delegated.localAddress!!

    override fun isOpen(): Boolean = delegated.isOpen

    override fun isClosing(): Boolean = !isOpen

    override fun isFlushAndClose(): Boolean {
        TODO("Not yet implemented")
    }

    override fun isClosed(): Boolean = !isOpen

    override fun getDraft(): Draft {
        TODO("Not yet implemented")
    }

    override fun getReadyState(): ReadyState {
        TODO("Not yet implemented")
    }

    override fun getResourceDescriptor(): String {
        TODO("Not yet implemented")
    }

    override fun <T : Any?> setAttachment(p0: T) {
        TODO("Not yet implemented")
    }

    override fun <T : Any?> getAttachment(): T {
        TODO("Not yet implemented")
    }

    override fun hasSSLSupport(): Boolean {
        TODO("Not yet implemented")
    }

    override fun getSSLSession(): SSLSession {
        TODO("Not yet implemented")
    }

    override fun getProtocol(): IProtocol {
        TODO("Not yet implemented")
    }
}

最后自行注册即可

@Configuration
@EnableWebSocket
class WSConfig:WebSocketConfigurer {
    override fun registerWebSocketHandlers(registry: WebSocketHandlerRegistry) {
        registry.addHandler(
            WSHandler(),
            "bot"
        )
    }
}

补一个上文中出现的工具类

@file:Suppress("INVISIBLE_MEMBER", "INVISIBLE_REFERENCE")
package top.kagg886.youmu.backend.socket

import net.mamoe.mirai.Bot
import org.springframework.web.socket.WebSocketSession
import top.kagg886.youmu.bot.internal.spring.SpringDelegatedWebSocket
import top.mrxiaom.overflow.internal.contact.BotWrapper
import kotlin.reflect.KProperty1
import kotlin.reflect.full.memberProperties
import kotlin.reflect.jvm.isAccessible

fun Bot.getOriginChannel(): WebSocketSession {
    val prop = BotWrapper::class.memberProperties.first { it.name == "implBot" } as KProperty1<BotWrapper, cn.evolvefield.onebot.client.core.Bot>
    prop.isAccessible = true
    val wrapper = prop.get(this as BotWrapper).channel
    return (wrapper as SpringDelegatedWebSocket).delegated
}

最后附赠一套使用此方案部署在公网上的反向websocket bot：

wss://youmu.kagg886.top/bot

接入教程见此：部署bot

kagg886

补充：

由于网络延迟原因，可能需要增大overflow对onebot api响应的等待时间，在启动类的main方法添加属性以增大等待时间：

System.getProperties().setProperty("overflow.timeout",1.minutes.inWholeMilliseconds.toString())

由于Spring Websocket分包问题，需要增大Tomcat默认处理ws的缓冲区，推荐将发送图片大小压缩到2M以内，同时在启动类添加属性：

System.getProperties().setProperty("org.apache.tomcat.websocket.DEFAULT_BUFFER_SIZE","5242880")