basic-validator

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: []
// }