replace string through stream

stream.js

// 1
let body = []
proxyRes.on('data', chunk => {
  body.push(chunk)
})
proxyRes.on('end', () => {
  body = Buffer.concat(body).toString()
    .replace(/\/dist\/rsa-ui/g, `${MLISA_BASE_URL_PREFIX}/dist/rsa-ui`)
  isTextFile(req)
    ? res.end(body)
    : res.end()
})

// 2
if (isTextFile(req)) {
  proxyRes
    .pipe(replace(/\/dist\/rsa-ui/g, `${MLISA_BASE_URL_PREFIX}/dist/rsa-ui`))
    .pipe(res)
} else {
  proxyRes.on('data', () => {})
  proxyRes.on('end', () => res.end())
}

// 3
const replacer = replace(/\/dist\/rsa-ui/g, `${MLISA_BASE_URL_PREFIX}/dist/rsa-ui`)
replacer.pipe(res)
proxyRes.on('data', data => {
  if (isTextFile(req)) replacer.write(data)
  else replacer.write('')
})
proxyRes.on('end', () => replacer.end())