RegExp in worker_threads

index.js

// access to http://localhost:3000?n=65536

const http = require('http')
const {URL} = require('url')
const {Worker} = require('worker_threads')

const rex = /\s+$/

const sleep = ms => new Promise(resolve => setTimeout(resolve, ms))

const main = () => {
  const server = http.createServer((req, res) => {
    const url = new URL(req.url, 'http://localhost:3000')
    if (url.pathname === '/') {
      const text = ' '.repeat((url.searchParams.get('n') | 0) + 1) + 'a'
      const pattern = rex.source
      const worker = new Worker('./worker.js', { workerData: { text, pattern }})
      const asyncRexTest = async () => {
        return new Promise((resolve, reject) => {
          worker.on('message', resolve)
          worker.on('error', reject)
          worker.on('exit', reject)
        })
      }
      Promise.race([
        asyncRexTest(),
        sleep(1000)
      ]).then(result => {
        res.writeHead(200, {'Content-Type': 'text/html;charset=utf-8'})
        if (result === undefined) {
          worker.terminate()
          res.end('timeout')
        } else {
          res.end(result.toString())
        }
      }).catch(error => {
        console.error(error)
        res.writeHead(500, {'Content-Type': 'text/html;charset=utf-8'})
        res.end('Internal Server Error')
      })
    } else {
      res.writeHead(404, {'Content-Type': 'text/html;charset=utf-8'})
      res.end('Not Found')
    }
  })
  server.listen(3000)
}

main()

worker.js

const { workerData, parentPort } = require('worker_threads')
const { text, pattern } = workerData

const re = new RegExp(pattern)
console.log(text.length, pattern, re)
console.time()
parentPort.postMessage(re.test(text))
console.timeEnd()