basic-validator

Installation

yarn add basic-validator or npm install basic-validator

Usage

Import

Import or require Validator to be consumed:

import { Validator } from 'basic-validator';

Create Validator

Once imported, instantiate with:

const password = new Validator();

Validator methods

| method | argument | description | | --------------------------------------------------------- | --------------------- | ----------------------------------------------------------------------------------------------------- | | rule() | Object {} | Add a validation rule | | validate() | Value to be validated | Loop over all validation rules, returning an object containing valid (boolean) and errors (array) |

Adding rules with .rule({...obj})

To add a rule to a validator, call rule({}) on the Validator instance, passing the following object {}:

| param | required | type | description | | --------- | -------- | -------- | ------------------------------------------------ | | fn | yes | Function | Function to be called when validating | | message | yes | String | Message to be added to errors array upon failure | | params | no | Array | Parameters (in order) to be passed to function |

⭐ Rule expectations

• The function (fn) passed to the rule must return true or false. These can be custom validation functions or imported from many of the validation libraries.
• The function (fn) must accept the testing value as its first parameter.
• If parameters (params) are passed to the rule, they must be in order as per the functions documentation.

Example usage:

password.rule({
  fn: containsSpecialChar,
  message: 'Must contain special character'
});

password.rule({
  fn: charsBetween,
  message: 'Characters must be between 10 and 15',
  params: [10, 15]
});

Rules can also be chained:

password
  .rule({
    fn: charsBetween,
    params: [10, 15],
    message: 'Chars need to be between 10 and 15'
  })
  .rule({
    fn: containsUnderscore,
    message: 'Must contain an underscore'
  })
  .rule({
    fn: containsDash,
    message: 'Must contain a dash'
  });

Validating with .validate(val)

Once the Validator has been created and rules added, running validation can be called with .validate(val) - passing the value to be validated. The validate function will return an object containing two keys; valid and errors.

The key valid will be a boolean, errors will be an array of messages defined from the rules.

For example:

password.validate('hello');
// {
//   valid: false,
//   errors: ['Must contain an underscore', 'Must contain a dash']
// }
password.validate('pass-word_here');
// {
//   valid: true,
//   errors: []
// }