main.js

// imports
require('dotenv').config()
const express = require('express')
const mongoose = require('mongoose')
const session = require('express-session')

const app = express()
const PORT = process.env.PORT || 4000

// database connection
mongoose.connect(process.env.DB_URI, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
})
const db = mongoose.connection
db.on('error', (error) => console.log(error))
db.once('open', () => console.log('connected to the database'))

// middlewares
app.use(express.urlencoded({ extended: false }))
app.use(express.json())

app.use(session({
    secret: 'my secret key',
    saveUninitialized: true,
    resave: false,
}))

app.use((req, res, next) => {
    res.locals.message = req.session.message
    delete req.session.message
    next()
})

app.use(express.static('uploads'))

// set template engine
app.set('view engine', 'ejs')

// route prefix
app.use('/', require('./routes/routes'))

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