React 应用程序中的 require('child_process').fork 方法“不存在”

Question

I want to run another nodejs script from a React app I'm writing with node. I've already used before this post a method I found on this forum, to achieve a similar thing, and it worked just fine: https://stackoverflow.com/a/22649812/11340913 . This is my App.js fragment:

import React from 'react';
import Peer from 'peerjs';

const childProcess = require('child_process');

function runScript(scriptPath, callback) {

    // keep track of whether callback has been invoked to prevent multiple invocations
    let invoked = false;

    let process = childProcess.fork(scriptPath);

    // listen for errors as they may prevent the exit event from firing
    process.on('error', err => {
        if (invoked) return;
        invoked = true;
        callback(err);
    });

    // execute the callback once the process has finished running
    process.on('exit', code => {
        if (invoked) return;
        invoked = true;
        var err = code === 0 ? null : new Error('exit code ' + code);
        callback(err);
    });

}

// Now we can run a script and invoke a callback when complete, e.g.
runScript('./node_modules/peer/bin/peerjs', err => {
    if (err) throw err;
    console.log('started p2p server!');
});

const peer = new Peer('banana_nebuna123' ,{
  key: 'peerjs',
  port: 9000,
  host: '127.0.0.1',
  secure: false,
  //path: '/home/eugen/Documents/scripts/ReactProjects/ShareLife/node_modules/peer/bin/peerjs'
}); 

function App() {
  
  return (
    <>
      <h1>
        hello, world!
      </h1>
    </>
  );
}

export default App;

This is the error I'm getting:

TypeError: childProcess.fork is not a function

runScript
src/App.js:11

 8 | // keep track of whether callback has been invoked to prevent multiple invocations 9 | let invoked = false; 10 | > 11 | let process = childProcess.fork(scriptPath); | ^ 12 | 13 | // listen for errors as they may prevent the exit event from firing 14 | process.on('error', err => {

Answer 1

Node's child_process module, like Node itself, runs in the backend (on the server) and so cannot be run in the browser which lacks access to the operating system in which child processes run. You might look into web workers which provide similar functionality within the browser.