Feature Request: Get subset of request data filtered by validation rules

Hello!

Thank you for this great module. However, I’m looking for a way to get a subset of request data filtered by validation rules.

I will give a small example:

/** Imagine that this is the request body.
{
  firstName: 'Slava',
  lastName: 'Fomin',
  email: '[e-mail]',
  password: 'some-pass-here',
  someExtra: 'foo'
}
*/

// I'm using this map to specify validation rules for the request.
req.checkBody({
  firstName: {},
  lastName: {},
  email: {
    notEmpty: {
      errorMessage: 'Missing E-Mail'
    },
    isEmail: {
      errorMessage: 'Incorrect E-Mail address'
    }
  }
});

var errors = req.validationErrors(true);
if (errors) {
  return res.json(400, {
    errors: errors
  });
}

var requestParams = req.getValidatedBody();

// We are getting only parameters specified during the validation phase,
// the extra request parameters, like "password", are ignored.
console.log(requestParams);

/**
{
  firstName: 'Slava',
  lastName: 'Fomin',
  email: '[e-mail]'
}
*/

That way I will be able to use the entire object without the fear of overwriting some protected property later on (e.g. when updating user entity).

[gustavohenke]

Hello folks! v4.0.0 has finally been released!

You can now get the subset of data matched by any validations by using the new APIs check and filter:

const { check, validationResult } = require('express-validator/check');
const { matchedData } = require('express-validator/filter');

app.post('/', [
  check('username').isLength({ min: 1 }).isEmail(),
  check('password').isLength({ min: 1 })
], (req, res, next) => {
  // data will only contain valid validated data by default
  const data = matchedData(req);

  // you can also get all validated data, even the invalid ones:
  const data = matchedData(req, { onlyValidData: false });
});

Please check the README for complete docs, and also check the upgrade guide.

[lock[bot]]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.