wo-core-rpcsocket/rpcsocket.js

const ws = require('ws')
const { randomBytes } = require('crypto')

// 建议把 onopen, onerror, onclose, onmessage 保留给系统使用，例如reconnecting。用户使用 on(event, listener)

const DAD = (module.exports = class RpcSocket extends ws {
  constructor(address, protocols, options) {
    let ws = super(address, protocols, options)
    DAD.upgrade(ws)
  }

  static upgrade(ws) {
    ws.__proto__ = DAD.prototype
    ws.sid = randomBytes(16).toString('hex')

    ws.onmessage = async ({ data }) => {
      // console.log('[onmessage] 被调用在 data =', data)
      try {
        let { rpcType, rpcHow, rpcWhat, randomEvent, rpcResult } = JSON.parse(data)
        // console.log('message data parsed to ', {rpcType, rpcHow, rpcWhat, randomEvent, rpcResult})
        switch (rpcType) {
          case 'SEND_REQUEST':
            // 接收到异步的远程调用
            // console.log(`被调方 收到 SEND_REQUEST: rpcHow=${rpcHow}, rpcWhat=${JSON.stringify(rpcWhat)}`)
            if (ws.hasOwnProperty(rpcHow)) rpcResult = await ws[rpcHow](rpcWhat)
            else rpcResult = { _state: 'ERROR', _stateMsg: `unknown rpcHow=${rpcHow}` }
            if (randomEvent) {
              ws.send(JSON.stringify({ rpcType: 'SEND_RESULT', randomEvent, rpcResult })) // 返回结果给远程
            }
            break
          case 'SEND_RESULT':
            // 接收到远程返回的结果
            // console.log('主调方 收到 SEND_RESULT: rpcResult=', rpcResult)
            ws.emit(randomEvent, rpcResult)
            break
          case 'SEND_NOTIFY':
          default:
            // 接收到同步的远程调用 或者 标准ws的send(...)
            // console.log(`被调方 收到 SEND_NOFITY: rpcHow=${rpcHow}, rpcWhat=${JSON.stringify(rpcWhat)}`)
            if (ws.hasOwnProperty(rpcHow)) ws[rpcHow](rpcWhat)
            else if (ws.eventNames().indexOf(rpcHow) >= 0) ws.emit(rpcHow, rpcWhat)
            else console.error('[onmessage] unknown rpc: ', rpcHow, rpcWhat)
            break
        }
      } catch (exception) {
        console.error('[onmessage] invalid rpc data: ', data, exception)
        return
      }
    }

    return ws
  }

  static connectAsync(url) {
    return new Promise(function (resolve, reject) {
      let socket = new DAD(url)
      socket.onopen = () => resolve(socket)
      socket.onerror = (err) => reject(err)
    })
  }

  reconnectAsync(url) {
    if (this.readyState === ws.CONNECTING || this.readyState === ws.OPEN) {
      return Promise.resolve(this)
    }
    return new Promise((resolve, reject) => {
      let socket = new DAD(url || this.url)
      socket.once('open', () => resolve(socket))
      socket.once('error', (err) => reject(err))
    })
  }

  sendNotify({ rpcHow, rpcWhat, options, callback } = {}) {
    // 发起同步的远程调用
    this.send(JSON.stringify({ rpcType: 'SEND_NOTIFY', rpcHow, rpcWhat }), options, callback)
  }

  sendRequest({ rpcHow, rpcWhat, rpcCallback, timeout = 5000 } = {}) {
    // 发起异步的远程调用
    let randomEvent = randomBytes(16).toString('hex')
    //    console.log('randomEvent is randomized: ', randomEvent)
    if (typeof rpcCallback === 'function') {
      // 有回调
      this.send(JSON.stringify({ rpcType: 'SEND_REQUEST', rpcHow, rpcWhat, randomEvent }), () => {
        //        console.log('in callback, randomEvent=', randomEvent)
        this.once(randomEvent, rpcCallback)
        setTimeout(() => {
          if (this.eventNames().indexOf(randomEvent) >= 0) {
            this.removeAllListeners(randomEvent)
            rpcCallback({ _state: 'RPC_REQUEST_TIMEOUT', _stateMsg: `RpcSocket sendRequest timeout: ${rpcHow} ${rpcWhat}` })
          }
        }, timeout)
      })
    } else {
      // 没有回调
      return new Promise((resolve, reject) => {
        this.send(JSON.stringify({ rpcType: 'SEND_REQUEST', rpcHow, rpcWhat, randomEvent }), () => {
          this.once(randomEvent, resolve)
          setTimeout(() => {
            if (this.eventNames().indexOf(randomEvent) >= 0) {
              this.removeAllListeners(randomEvent)
              resolve({ _state: 'RPC_REQUEST_TIMEOUT', _stateMsg: `RpcSocket sendRequest timeout: ${rpcHow} ${rpcWhat}` })
            }
          }, timeout)
        })
      })
    }
  }
})

// (async ()=>{

//   new RpcSocket('http://localhost:9007')
//   await sleep(20000)
//   new RpcSocket.Server({port:9007})
//   await sleep(20000)

// })()

/*
const sleep = (ms) => new Promise((resolve, reject) => setTimeout(resolve, ms))
//RpcSocket=require('./Ling/RpcSocket.js'); 
server = new RpcSocket.Server({port:6000}); 
var serverSocket; server.on('connection', (socket)=>{console.log('socket coming'); 
serverSocket = RpcSocket.upgrade(socket).on('close', (code, reason)=>console.log('socket is closed for code and reason: ', code, reason))
.on('error', (errer)=>console.log('socket has error: ', error))
})

RpcSocket.connectAsync('http://localhost:6000').then((clientSocket)=>{
  clientSocket.request('testfunc', {height:99}, (rpcResult)=>console.log('using request: ', rpcResult), 3000)
  return clientSocket
}).then((clientSocket)=>{
  console.log('sleeping...')
  sleep(2000)
  return clientSocket
}).then(async (clientSocket)=>{
  let rpcResult = await clientSocket.sendRequest('testfunc', {height:99}, 3000).catch(console.log)
  console.log('using sendRequest:', rpcResult)
  process.exit()
}).catch((e)=>{
  console.log('connect error happens:', e)
})
*/