Problems with async await in registerAsync

Environment info

Validatorjs version: 3.22.1 Node.js version: v12.18.3

Problem

I need the same functionality of issue #345, I want check in my database if the new value is unique, but the validation is not working as it should.

Implementation - Register Async

const Validator = require('validatorjs');
const services = require('../../index');
const NotFoundError = require('../errors/http-error');

Validator.registerAsync('unique', async (value, requirement, param, passes) => {
  if (typeof requirement !== 'string') {
    throw new Error('Invalid unique rule, you must enter the table!');
  }

  const args = requirement.split(',');

  const entityName = args[0];
  const field = args[1] || 'id';

  if (Object.keys(services).includes(entityName) === false) {
    throw new Error(`The entity ${entityName} doesn't exist.`);
  }

  const filters = {};
  filters[field] = value;

  /** @var {object} repository */
  const repository = services[entityName];

  try {
    await repository.getFirst(filters);
  } catch (error) {
    if (error instanceof NotFoundError) {
      passes(false, `The ${param} is already registered.`);
    }

    throw error;
  }

  await passes(true);
  return true;
});

module.exports = Validator;

Implementation - Validation

const Validator = require('../../lib/validatorjs'); // Import previous code 

const data = {
  name: 'Name',
  email: '[e-mail]',
  password: 'password',
};

const rules = {
  name: 'required',
  email: 'required|unique:users,email',
  password: 'required',
};

const validation = new Validator(data, rules);

const passes = () => {};

const fails = () => {
  const message = JSON.stringify(validation.errors.all());
  throw new UserInputError(message);
};

await validation.checkAsync(passes, fails);

Expected behaviour

Wait for await validation.checkAsync(passes, fails); and throw an exception.

Current behavior

The code below is taken from Implementation - Register Async

passes(false, `The ${param} is already registered.`);`

When the logic of the code does not go through the above section everything happens as it should.

When the code logic goes through the above section, the code does not respect the await validation.checkAsync(passes, fails); and the exception is returned asynchronously, breaking the application logic.

When this snippet is inserted before the line with await, the code behaves as expected.

[feeh27]

I am very grateful for the feedback, as I said earlier, I am willing to contribute, however, as I still do not understand the operation of registerAsync and checkAsync I do not know where to start.

If you show me the way (when possible), I can contribute to the solution.

[wulfsolter]

Cleaning up the approach that @feeh27 did a little bit, this is what I’m using:

    const validation = new Validator(data, rules, customErrorMessages);
    const validatorPromise = new Promise((resolve) => { validation.checkAsync(() => { resolve(true); }, () => { resolve(false); }); });
    const result = await validatorPromise;

    // failed validation
    if (result === false) {
      const allErrors = validation.errors.all();
      ...