为什么在 fork 处理来自数据处理器的消息总是空白

问题描述

计算需要很多时间，所以我使用了 fork 过程，面对来自数据处理器的消息的困难，我需要发送我的计算值作为响应，但为什么总是得到声明的变量 totalSum空白。检查以下语法。

app.js

 const cluster = require("cluster");
    const { fork } = require("child_process");
    const path = require("path");
    
    exports.get_company_total_sum = async (req,res,next) => {
      try {
        const { hs_object_id: companyId,hs_parent_company_id } = req.query;
        //const companyId = hs_object_id;
        console.log("hs_object_id",companyId);
    
        const processpath = path.join(
          __dirname,"..","9-services","tierone_carrier_dataProcess.js"
        );
    
        let totalSum = "";
        const child = fork(processpath);
        child.send({ companyId });

//process the messages coming from the task processor

        child.on("message",(response) => {
          console.log("response::",response.result);
          //return res.json({ message: response.message });
          totalSum = response.result;
        });
    
        //remove prevIoUsly openned node instance when we finished
        child.on("close",function (msg) {
          this.kill();
        });
    
        return res.json({ "total sum": totalSum });
    };

tierone_carrier_dataProcess.js

process.on("message",(payload) => {
  if (payload.companyId !== "") {
    const sum = longcomputation(payload);

    process.send({ result: sum });

    process.disconnect();
  }
});

function longcomputation(payload) {
  let sum = 0;
  for (let i = 0; i < payload.companyId; i++) {
    sum += i;
  }
  return sum;
}

process.on("uncaughtException",function (err) {
  console.log("Error happened: " + err.message + "\n" + err.stack + ".\n");
  console.log("Gracefully finish the routine.");
});

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

如果你已经找到好的解决方法，欢迎将解决方案带上本链接一起发送给小编。

小编邮箱:dio#foxmail.com (将#修改为@）

fork fork