server.js

const express = require('express')
const bodyParser = require('body-parser')
const { translate } = require('./translate')
const cors = require('cors')
const fs = require('fs')
const app = express()
const PORT = 7860

app.use(cors({ origin: '*' }))
app.use(bodyParser.json())

let delay = 1500
const delayIncrement = 100
const maxDelay = 5000
let currentTranslations = 0

function delayFileTermination(delay) {
  if (fs.existsSync('delay.txt')) {
    delay = parseInt(fs.readFileSync('delay.txt', 'utf8'))
  }else{
    fs.writeFile('delay.txt', 'delay:{$delay}', function(err){
      if(err = null){
        console.log('success')
      }else{
        console.log('fail')
      }
    })
  }  
}



console.log('File system loaded')

app.post('/translate', async (req, res) => {

  console.log('Translate start')
  currentTranslations++

  const { text, source_lang, target_lang } = req.body

  try {
    await new Promise(resolve => setTimeout(resolve, delay))

    const result = await translate(text, source_lang, target_lang)
    const responseData = {
      alternatives: result.alternatives,
      code: 200,
      data: result.text,
      id: Math.floor(Math.random() * 10000000000),
      method: 'Free',
      source_lang,
      target_lang,
    }
    res.json(responseData)
    console.log(`"${text}" -> "${result.text}"`)

  } catch (error) {
    console.log('Translation failed : ${error}')
    delay = delay + 100
    delayFileTermination(delay)
    console("현재 Delay 타임:" + delay + "ms")
  } finally {
    currentTranslations-- // 번역 처리가 끝나면 1 감소
  }
})

app.get('/', (req, res) => {
  const delayMessage = fs.existsSync('delay.txt') ? fs.readFileSync('delay.txt', 'utf8') : '0'
  const statusMessage = `서버가 구동되었습니다. 현재 딜레이 시간은 ${delay}ms이며, 현재 처리 중인 번역 요청 수는 ${currentTranslations}건입니다.`
  res.send(statusMessage)
  
})

app.listen(PORT, () => {
  console.log(`Server is running on http://localhost:${PORT}`)
})