server.js

require("dotenv").config();
const express = require('express');
const path = require('path');
const cors = require('cors');
const Participant = require('./models/Participant');
const mongoose = require("mongoose");
const {check, validationResult} = require('express-validator');


mongoose.connect(process.env.MONGO_URI)
  .catch((error) => {
    console.log("Connection to database failed:", error);
  })
  .then(() => {
    console.log("Successfully connected to database");
});

const app = express();
app.use(express.json());
app.use(express.static(path.join(__dirname, 'public')));
app.use(cors());
app.use(express.urlencoded({extended: true}));

app.get('/', (req, res) => {
res.sendFile(path.join(__dirname, '/index.html'));
})

app.post('/participants', [
    check('email', 'email is required !').not().isEmpty(),
    check('email', 'Invalid email !').isEmail().isLength({ min: 10, max: 30 }),
    check('fullname', 'fullname is required !').not().isEmpty(),
    check('fullname', 'Please enter your real name !').isLength({ min: 5, max: 50 }),
    check('motivation', 'Motivation is required !').not().isEmpty(),
    // check('motivation', 'FirstName length should be 3 to 30 characters').isLength({ min: 5, max: 50 }),
    // check('lastname', 'Lastname is required').not().isEmpty(),
    // check('lastname', 'LastName length should be 3 to 30 characters')
    //                 .isLength({ min: 3, max: 30 })
], 
async (req, res, next) => {
    try {
        const errors = validationResult(req);
        if (!errors.isEmpty()) return res.status(200).json({err: true, errors: errors.errors});

        const exists = await Participant.findOne({ email : req.body.email }).exec();
        if(exists) return res.status(200).json({err: true, errors: [{msg: 'Email already registered !'}]});
        
        const newParticipant = new Participant({
            email: req.body.email.toLowerCase(),
            fullname: req.body.fullname.toLowerCase(),
            // lastname: req.body.lastname.toLowerCase(),
            speciality: req.body.speciality.toLowerCase(),
            level: req.body.level.toLowerCase(),
            discord: req.body.discord.toLowerCase(),
            motivation: req.body.motivation.toLowerCase()
        });

        const result = await newParticipant.save();
        if(result) return res.status(200).json({err: false, msg: 'Successfully registered !'});
        return res.status(200).json({err: true, errors: [{msg: 'Something went wrong !'}]});
    }
    catch( err )
    {
        console.log('something went wrong : ' + err.message);
        return res.status(200).json({err: true, errors: [{msg: 'Something went wrong !'}]});
    }
});


const PORT = process.env.PORT || 3003;
app.listen(PORT, () => {
  console.log(`Server listening on port ${PORT}`);
});