如何访问内部函数数据javascript

Question

我有一个内部函数onMessage，它有一个参数消息，我想将它存储在一个变量中，并将其作为主函数的返回发送。

但问题是I无法访问onMessage函数之外的消息

我尝试过将它存储在变量 fusedata 中，但是当我在函数外打印fusedata时，im得到了未定义的。

不管怎样，我可以改进这个代码吗？

const { createDfuseClient,InboundMessage ,InboundMessageType } = require("@dfuse/client")

global.nodeFetch = require("node-fetch");
global.WebSocket = require("ws");
let fusedata;
async function dfuseListener()
{

  const client = createDfuseClient({
    apiKey: 'mobile_<MY-API-KEY>',
    network: "jungle",

    httpClientOptions: {
        fetch: nodeFetch,

      },

      streamClientOptions: {
        socketOptions: {
          webSocketFactory: async (url) => {

            const webSocket = new WebSocket(url, {
              handshakeTimeout: 30 * 1000, // 30s
              maxPayload: 200 * 1024 * 1000 * 1000 // 200Mb

                        })
            const onUpgrade = (response) => {
              console.log("Socket upgrade response status code.", response.statusCode)

              // You need to remove the listener at some point since this factory
              // is called at each reconnection with the remote endpoint!
              webSocket.removeListener("upgrade", onUpgrade)
            }

            webSocket.on("upgradeurl", onUpgrade)

            return webSocket
          }
        }
      }

  })


  const onMessage = (message) => {
    console.log('onMessage :')    
    fusedata=message;
    console.log('im working ',message);
    if (message.type === InboundMessageType.PROGRESS) {
      // updateProgress(networkName, message);
    } else if (message.type === InboundMessageType.ACTION_TRACE) {
    //  updateAction(message.data);
    } else {
      console.log(message);
    }

  }

  const stream = await client.streamActionTraces(
    {
      accounts: "guru11111111"
    },
    onMessage,
    {
      start_block:  52797826,
      with_progress: 60
    },console.log('hey its here')
  )  

  console.log("Socket is now connected.",fusedata)

  return{
      onMessage
  }

}
module.exports=dfuseListener;

Answer 1

可能是个很长的机会，但是试试这样的方法

  const onMessage = (message) => {
    console.log('onMessage :')    
    fusedata=message;
    console.log('im working ',message);
    if (message.type === InboundMessageType.PROGRESS) {
      // updateProgress(networkName, message);
    } else if (message.type === InboundMessageType.ACTION_TRACE) {
    //  updateAction(message.data);
    } else {
      console.log(message);
    }
    return message;
  }

 const yourVariableName = onMessage(message)