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Asynchronous Validation - Validating If Username Exists.

See original GitHub issue

Hi,

I’m having a problem using Async functions to validate whether a username exists.

server.js

app.use(validator({

    customValidators: {

        isUsernameAvailable: function(username) {
            return new Promise(function(resolve, reject) {

                User.findOne({'username': username}, function(err, results) { 

                    if(err) {
                        return resolve(err);
                    }
                    reject(results);

                });

            });
        }
    }

}));

auth.middleware.js

module.exports.register = function(req, res, next)
{
    req.checkBody({

        'username': {
            notEmpty: true,
            errorMessage: 'Username is required'
        },

        'email': {
            notEmpty: true,
            isEmail: {
                errorMessage: 'Invalid Email Address'
            },
            errorMessage: 'Email is required'
        },

        'password': {
            notEmpty: true,
            errorMessage: 'Password is required'
        },

        'password_confirmation': {
            notEmpty: true,
            errorMessage: 'Password Confirmation is required'
        }

    });

    req.assert('password_confirmation', 'Passwords do not match').equals(req.body.password);

    req.check('username', 'This username is already taken').isUsernameAvailable();

    req.asyncValidationErrors().catch(function(errors) {

        if(errors) {
            return res.json({
                success:false,
                errors: errors
            });
        };
    });

    var errors = req.validationErrors(true);

    if(errors) {

        return res.json({
            success: false,
            errors: errors
        });

    }

    next();
}

auth.controller

module.exports.register = function(req, res) {

    var input = req.body;

    var user = new User({

        username: input.username,
        email: input.email,
        password: input.password

    });

    user.save(function(err) {

        if(err) {
            return res.json(err);
        }

        return res.json({
            success: true,
            status: 'Successfully Registered User'
        });

    });

}

auth.route


router.post('/register', middleware.register, controller.register);

My server crashes with:

WARNING: You have asynchronous validators but you have not used asyncValidateErrors to check for errors.

Error: Can’t set headers after they are sent.

its trying to set headers because its called next() when i actually want it to return the error and stop.

Issue Analytics

State:
Created 8 years ago
Reactions:1
Comments:5 (1 by maintainers)

Top GitHub Comments

4reactions

jalfcolombiacommented, Feb 17, 2016

Hello, I’ve been able solved. Thanks @Jakeii. Thanks to this link

The file is as follows

auth.middleware.js

module.exports.register = function(req, res, next)
{
    req.checkBody({

        'username': {
            notEmpty: true,
            errorMessage: 'Username is required'
        },

        'email': {
            notEmpty: true,
            isEmail: {
                errorMessage: 'Invalid Email Address'
            },
            errorMessage: 'Email is required'
        },

        'password': {
            notEmpty: true,
            errorMessage: 'Password is required'
        },

        'password_confirmation': {
            notEmpty: true,
            errorMessage: 'Password Confirmation is required'
        }

    });

    req.assert('password_confirmation', 'Passwords do not match').equals(req.body.password);

    req.check('username', 'This username is already taken').isUsernameAvailable();

    req.asyncValidationErrors().then(function() {
        next();
    }).catch(function(errors) {

        if(errors) {
            return res.json({
                success:false,
                errors: errors
            });
        };
    });
}

1reaction

Jakeiicommented, Feb 17, 2016

You’re using asyncValidationErrors() and validationErrors().

asyncValidationErrors() returns all errors async or not, no need to call validationErrors() as well.

On Tue, 16 Feb 2016 23:41 Julian Lasso notifications@github.com wrote:

Hi guys. Do you already able to solve the problem? I have also the same problem! 😦

— Reply to this email directly or view it on GitHub https://github.com/ctavan/express-validator/issues/199#issuecomment-184867243 .