Извлечение строк путем сравнения двух строк через nodejs

Здесь у вас есть:

const fs = require('fs')
const readline = require('readline')

// we will save the result in this array
const result = []

let afterUser = false

const rl = readline.createInterface(fs.createReadStream('text.txt'))

const listener = rl.on('line', line => {
  // finish the listener if we reach Response line
  if (line === 'Response') {
    rl.close()
    return
  }

  // if we are after User line push the item to the array
  if (afterUser) {
    result.push(line)
  }

  // we'll set afterUser to true if we detect the User line
  if (!afterUser && line === 'User') {
    afterUser = true
  }
})

// after finish reading the file we can show the result
rl.on('close', () => {
  console.info(result)
})