how to do confirm email address with express/node?

Question

Im trying to build confirm email address for users, to verify their email is real. What package should i use to confirm the email address of the user. So far Im using mongoo

Answer 1

Step 1:

User Model

var userSchema = new mongoose.Schema({
    email: { type: String, unique: true },
    isVerified: { type: Boolean, default: false },
    password: String,
  });

Token Model

const tokenSchema = new mongoose.Schema({
    _userId: { type: mongoose.Schema.Types.ObjectId, required: true, ref: 'User' },
    token: { type: String, required: true },
    expireAt: { type: Date, default: Date.now, index: { expires: 86400000 } }
});

Step 2: Login

exports.login = function(req, res, next) {
    User.findOne({ email: req.body.email }, function(err, user) {
        // error occur
        if(err){
            return res.status(500).send({msg: err.message});
        }
        // user is not found in database i.e. user is not registered yet.
        else if (!user){
            return res.status(401).send({ msg:'The email address ' + req.body.email + ' is not associated with any account. please check and try again!'});
        }
        // comapre user's password if user is find in above step
        else if(!Bcrypt.compareSync(req.body.password, user.password)){
            return res.status(401).send({msg:'Wrong Password!'});
        }
        // check user is verified or not
        else if (!user.isVerified){
            return res.status(401).send({msg:'Your Email has not been verified. Please click on resend'});
        } 
        // user successfully logged in
        else{
            return res.status(200).send('User successfully logged in.');
        }
    });

});

Step 3: Sign Up

exports.signup = function(req, res, next) {
  User.findOne({ email: req.body.email }, function (err, user) {
    // error occur
    if(err){
        return res.status(500).send({msg: err.message});
    }
    // if email is exist into database i.e. email is associated with another user.
    else if (user) {
        return res.status(400).send({msg:'This email address is already associated with another account.'});
    }
    // if user is not exist into database then save the user into database for register account
    else{
        // password hashing for save into databse
        req.body.password = Bcrypt.hashSync(req.body.password, 10);
        // create and save user
        user = new User({ name: req.body.name, email: req.body.email, password: req.body.password });
        user.save(function (err) {
            if (err) { 
              return res.status(500).send({msg:err.message});
            }
            
            // generate token and save
            var token = new Token({ _userId: user._id, token: crypto.randomBytes(16).toString('hex') });
            token.save(function (err) {
              if(err){
                return res.status(500).send({msg:err.message});
              }

                // Send email (use credintials of SendGrid)
                var transporter = nodemailer.createTransport({ service: 'Sendgrid', auth: { user: process.env.SENDGRID_USERNAME, pass: process.env.SENDGRID_PASSWORD } });
                var mailOptions = { from: 'no-reply@example.com', to: user.email, subject: 'Account Verification Link', text: 'Hello '+ req.body.name +',\n\n' + 'Please verify your account by clicking the link: \nhttp:\/\/' + req.headers.host + '\/confirmation\/' + user.email + '\/' + token.token + '\n\nThank You!\n' };
                transporter.sendMail(mailOptions, function (err) {
                    if (err) { 
                        return res.status(500).send({msg:'Technical Issue!, Please click on resend for verify your Email.'});
                     }
                    return res.status(200).send('A verification email has been sent to ' + user.email + '. It will be expire after one day. If you not get verification Email click on resend token.');
                });
            });
        });
    }
    
  });

});

Step 4: Verify Account

// It is GET method, you have to write like that
//    app.get('/confirmation/:email/:token',confirmEmail)

exports.confirmEmail = function (req, res, next) {
    Token.findOne({ token: req.params.token }, function (err, token) {
        // token is not found into database i.e. token may have expired 
        if (!token){
            return res.status(400).send({msg:'Your verification link may have expired. Please click on resend for verify your Email.'});
        }
        // if token is found then check valid user 
        else{
            User.findOne({ _id: token._userId, email: req.params.email }, function (err, user) {
                // not valid user
                if (!user){
                    return res.status(401).send({msg:'We were unable to find a user for this verification. Please SignUp!'});
                } 
                // user is already verified
                else if (user.isVerified){
                    return res.status(200).send('User has been already verified. Please Login');
                }
                // verify user
                else{
                    // change isVerified to true
                    user.isVerified = true;
                    user.save(function (err) {
                        // error occur
                        if(err){
                            return res.status(500).send({msg: err.message});
                        }
                        // account successfully verified
                        else{
                          return res.status(200).send('Your account has been successfully verified');
                        }
                    });
                }
            });
        }
        
    });
});

Step 5: Resend Link

exports.resendLink = function (req, res, next) {

    User.findOne({ email: req.body.email }, function (err, user) {
        // user is not found into database
        if (!user){
            return res.status(400).send({msg:'We were unable to find a user with that email. Make sure your Email is correct!'});
        }
        // user has been already verified
        else if (user.isVerified){
            return res.status(200).send('This account has been already verified. Please log in.');
    
        } 
        // send verification link
        else{
            // generate token and save
            var token = new Token({ _userId: user._id, token: crypto.randomBytes(16).toString('hex') });
            token.save(function (err) {
                if (err) {
                  return res.status(500).send({msg:err.message});
                }
    
                // Send email (use credintials of SendGrid)
                    var transporter = nodemailer.createTransport({ service: 'Sendgrid', auth: { user: process.env.SENDGRID_USERNAME, pass: process.env.SENDGRID_PASSWORD } });
                    var mailOptions = { from: 'no-reply@example.com', to: user.email, subject: 'Account Verification Link', text: 'Hello '+ user.name +',\n\n' + 'Please verify your account by clicking the link: \nhttp:\/\/' + req.headers.host + '\/confirmation\/' + user.email + '\/' + token.token + '\n\nThank You!\n' };
                    transporter.sendMail(mailOptions, function (err) {
                       if (err) { 
                        return res.status(500).send({msg:'Technical Issue!, Please click on resend for verify your Email.'});
                     }
                    return res.status(200).send('A verification email has been sent to ' + user.email + '. It will be expire after one day. If you not get verification Email click on resend token.');
                });
            });
        }
    });
});

You can take help from this link:https://medium.com/@slgupta022/email-verification-using-sendgrid-in-node-js-express-js-mongodb-c5803f643e09