Mr. Checkbox

Validates a value against a given set of requirements. Named after a former colleague.

Mr. Checkbox (the function, not the person) is curried; validators can be created with partially-applied invocation.

Domain

A Requirement is an object with an error and validator. An error is any value, usually a string, that is used to identify any values that fail to meet the requirement. A validator is a function that accepts a value as input and returns true if the requirement is met; false if it is not met.

{
  error: 'minimumLength',
  validator: function (value) { return value.length > 8; }
}

Mr. Checkbox produces an array of error values. If the string abc were validated against the requirements above, the result would be: ['minimumLength'].

Usage & Examples

Using partial-application.

var mrCheckbox = require('mr-checkbox');

function isPalindrome(value) {
  return value === value.split('').reverse().join('');
}

var validatePassword = mrCheckbox([
  {
    error: 'Password must 8 characters or longer',
    validator: function (value) { return value.length > 7; }
  },
  {
    error: 'Password must be 50 characters or shorter',
    validator: function (value) { return value.length < 51; }
  },
  {
    error: 'Password cannot be "password"',
    validator: function (value) { return value !== 'password'; }
  },
  {
    error: 'Password cannot start with the letter Q.',
    validator: function (value) { return value.charAt(0) !== 'Q'; }
  },
  {
    error: 'Password must be a palindrome.',
    validator: isPalindrome
  }
]);

validatePassword('password');
  =>  [
        'Password cannot be "password"',
        'Password must be a palindrome.';
      ]


validatePassword('abc');
  =>  [
        'Password must 8 characters or longer',
        'Password must be a palindrome.'
      ]

validatePassword('QhannahhannahQ');
  =>  [ 'Password cannot start with the letter Q.' ]

validatePassword('iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii');
  =>  [ 'Password must be 50 characters or shorter' ]

validatePassword('hannahhannah');
  => []

Or, non-curried invocation.

var mrCheckbox = require('mr-checkbox');

function isPalindrome(value) {
  return value === value.split('').reverse().join('');
}

var requirements = [
  {
    error: 'Password must 8 characters or longer',
    validator: function (value) { return value.length > 7; }
  },
  {
    error: 'Password must be 50 characters or shorter',
    validator: function (value) { return value.length < 51; }
  },
  {
    error: 'Password cannot be "password"',
    validator: function (value) { return value !== 'password'; }
  },
  {
    error: 'Password cannot start with the letter Q.',
    validator: function (value) { return value.charAt(0) !== 'Q'; }
  },
  {
    error: 'Password must be a palindrome.',
    validator: isPalindrome
  }
];

mrCheckbox(requirements, 'password');
  =>  [
        'Password cannot be "password"',
        'Password must be a palindrome.';
      ]


mrCheckbox(requirements, 'abc');
  =>  [
        'Password must 8 characters or longer',
        'Password must be a palindrome.'
      ]

mrCheckbox(requirements, 'QhannahhannahQ');
  =>  [ 'Password cannot start with the letter Q.' ]

mrCheckbox(requirements, 'iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii');
  =>  [ 'Password must be 50 characters or shorter' ]

mrCheckbox(requirements, 'hannahhannah');
  => []

Changelog

• v1.1.2: Adds patch-, minor-, and major-release NPM scripts (6/23/16)
• v1.1.1: Adds eslint to project (6/21/16)
• v1.1.0: Replaces Ramda's curry with auto-curry (3/14/16)
• v1.0.0: Initial commit (3/11/16)