app.js

const LOG_PATH = 'logs'
const LOG_FILE = 'server.log'

const express = require('express')
const path = require('path')
const fs = require('fs')
const favicon = require('serve-favicon')
const morgan = require('morgan')
const cookieParser = require('cookie-parser')
const bodyParser = require('body-parser')

const index = require('./routes/index')
const api = require('./routes/api')

const ApiAccessor = require('./server/ApiAccessor')
const apiCache = require('./server/ApiCache')

// Middleware
const byIPDetector = require('./middleware/ByIPDetector')

// loggin settings
const FULL_LOG_PATH = path.join(LOG_PATH, LOG_FILE)

// check if LOG_PATH exist
if (!fs.existsSync(LOG_PATH)) {
  fs.mkdirSync(LOG_PATH)
  console.log('Log folder created.')
}

// check if LOG_FILE exist
if (!fs.existsSync(FULL_LOG_PATH)) {
  fs.writeFile(FULL_LOG_PATH, '', (err) => {
    if (err) {
      console.error('Log file not created!', err)
    } else console.log('Log file created.')
  })
}

let logFile = path.join(__dirname, FULL_LOG_PATH)
let logFileStream = fs.createWriteStream(logFile, { flags: 'a' })

let app = express()

console.log('Environment', app.get('env'))

if (app.get('env') === 'development') {
  let config = require('./config/default.json')

  process.env.OPENWEATHER_API_KEY = config['weatherService']['apiKey']
  process.env.SCHEDULER_PAUSE = config['schedulerPause']
}

// api accessor settings
let apiAccessor = ApiAccessor.create({
  apiKey: process.env.OPENWEATHER_API_KEY
})
app.set('apiAccessor', apiAccessor)

// view engine setup
app.set('views', path.join(__dirname, 'views'))
app.set('view engine', 'ejs')

// Log general server information to the console.
app.use(morgan('dev'))
// Write more specific log information to the server log file.
app.use(morgan('combined', { stream: logFileStream }))

// uncomment after placing your favicon in /public
// app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(byIPDetector)
app.use(bodyParser.json())
app.use(bodyParser.urlencoded({ extended: false }))
app.use(cookieParser())
app.use(express.static(path.join(__dirname, 'public')))

app.use('/', index)
app.use('/api', api)

// catch 404 and forward to error handler
app.use(function (req, res, next) {
  let err = new Error('Not Found')
  err.status = 404
  next(err)
})

// error handler
app.use(function (err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message
  res.locals.error = req.app.get('env') === 'development' ? err : {}

  // render the error page
  res.status(err.status || 500)
  res.render('error')
})

// schedulars
setInterval(async () => {
  let cache = apiCache.getInstance().getCache()
  let currentTime = new Date().getTime()

  for (let obj in cache) {
    // update current weather
    if (cache[obj].currentWeatherUpdateTime && (currentTime - cache[obj].currentWeatherUpdateTime >= process.env.SCHEDULER_PAUSE)) {
      console.log('Update current weather of', obj, 'city')
      try {
        apiAccessor.getCurrentWeather({id: obj})
        console.log('Current weather of city', obj, 'succesful updated')
      } catch (e) {
        console.error('Current weather of city not updated', e)
      }
    }

    // update forecast weather
    if (cache[obj].forecastWeatherUpdateTime && (currentTime - cache[obj].forecastWeatherUpdateTime >= process.env.SCHEDULER_PAUSE)) {
      console.log('Update forecast weather of', obj, 'city')
      try {
        await apiAccessor.getForecastWeather({id: obj})
        console.log('Forecast weather of city', obj, 'succesful updated')
      } catch (e) {
        console.error('Forecast weather not updated', e)
      }
    }
  }
}, process.env.SCHEDULER_PAUSE)

module.exports = app