Websocket emulator for Chrome devtools

Websocket emulator.js

/**
 * Transport layer emulator
 */
class Transport {
  constructor(/** @type {WebSocket} */ websocket) {
    this.send = (...args) => websocket._send(...args)
    this.close = () => websocket.close()
    this.onOpen()
  }

  onOpen() {}

  handleMessage(message) {
    if (message.method === 'Runtime.runIfWaitingForDebugger') {
      this.send({"id":1,"result":{}},
      {"method":"Runtime.executionContextCreated","params":{"context":{"id":1,"origin":"","name":"Worker"}}}	,
      {"method":"Runtime.consoleAPICalled","params":{"type":"error","args":[{"type":"string","value":"WOOT!"},{"type":"object","className":"MyCustomClass","description":"Request","objectId":"{\"injectedScriptId\":1,\"id\":1}"}],"executionContextId":1,"timestamp":0,"stackTrace":{"callFrames":[{"functionName":"fetchAndLog","scriptId":"11","url":"","lineNumber":9,"columnNumber":10}]}}}	,
      {"method":"Runtime.consoleAPICalled","params":{"type":"log","args":[{"type":"string","value":"CONSOLE %cFORMATTING :D"},{"type":"string","value":"color: red"}],"executionContextId":1,"timestamp":0,"stackTrace":{"callFrames":[{"functionName":"","scriptId":"41","url":"","lineNumber":0,"columnNumber":8}]}}},
      {"id":2,"result":{}},
      {"method":"Debugger.scriptParsed","params":{"scriptId":"11","url":"","startLine":0,"startColumn":0,"endLine":13,"endColumn":1,"executionContextId":1,"hash":"BE635EC24CF67059AB309333C8446C66D17DD491","isLiveEdit":false,"sourceMapURL":"","hasSourceURL":false,"isModule":false,"length":340}}	,
      {"id":3,"result":{"debuggerId":"(CA8E9A9BF34D00D1C7F3EDDA505A85A7)"}},
      {"id":4,"result":{}})
    }
  }
}

SDK.Logs = []
class WebSocket {
  readyState = 1
  url = null
  onopen = null
  onclose = null
  onmessage = null

  constructor(url) {
    this.url = url
    setTimeout(() => {
      this.check()
    })
  }

  check() {
    if (this.onopen) {
      this.open()
    } else {
      setTimeout(() => {
        this.check()
      }, 100)
    }
  }

  open() {
    this.transport = new Transport(this)
    this.onopen()
  }

  send(message) {
    try {
      message = JSON.parse(message)
    } catch (e) {
      console.error(`[WEBSOCKET-EMULATOR]`, 'Failed to parse message!', e)
      return
    }
    SDK.Logs.push(['SEND', message])
    this.transport.handleMessage(message)
  }

  _send(...messages) {
    for (let message of messages) {
      try {
        message = JSON.stringify(message)
      } catch (e) {
        console.error(
          `[WEBSOCKET-EMULATOR]`,
          'Failed to convert message into JSON!',
          e
        )
        return
      }
      SDK.Logs.push(['RECEIVE', message])
      if (this.onmessage) {
        this.onmessage({
          data: message
        })
      }
    }
  }

  close() {
    if (this.onclose) {
      this.onclose()
    }
    this.readyState = 3
  }
}