@drpiou/yum

The @drpiou/yum package provides a validator module written in TypeScript.

• Installation
• Documentation
  • Yum
    • Methods
      • label
      • transform
      • merge
      • nullable
      • required
      • clone
      • validate
      • validateSync
    • Types
      • mixed
      • mixedOf
      • string
        • format
        • include
        • range
        • regex
      • number
        • include
        • range
      • boolean
      • date
        • include
        • range
      • array
        • of
        • include
        • range
      • object
        • shape
  • Modules
    • Types
      • mixed
      • mixedOf
      • string
      • number
      • boolean
      • date
      • array
      • object
    • Rules
      • clone
      • custom
      • format
      • include
      • label
      • merge
      • nullable
      • of
      • or
      • range
      • regex
      • required
      • shape
      • transform
      • validate
      • validateSync

Installation

yarn add @drpiou/yum

Documentation

Yum

Methods

label

import { yum } from '@drpiou/yum';

const context = yum.string().label('MyString');

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

transform

import { yum } from '@drpiou/yum';

const context = yum.string().transform((s) => String(s).toUpperCase());

const result = context.validateSync('a');
// result[0] -> 'A'
// result[1] -> undefined

merge

import { yum } from '@drpiou/yum';

const base = yum.string().nullable(true);
const context = yum.string().merge(base);

const result = context.validateSync(null);
// result[0] -> null
// result[1] -> undefined

nullable

import { yum } from '@drpiou/yum';

const context = yum.string().label('MyString');

const result = context.nullable(true).validateSync(null);
// result[0] -> null
// result[1] -> undefined

const faulty = context.nullable(false).validateSync(null);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The field MyString cannot be null.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'nullable'
// faulty[1].reasons[0].condition -> false

required

import { yum } from '@drpiou/yum';

const context = yum.string().label('MyString');

const result = context.required(false).validateSync(undefined);
// result[0] -> undefined
// result[1] -> undefined

const faulty = context.required(true).validateSync(undefined);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The field MyString cannot be null.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'nullable'
// faulty[1].reasons[0].condition -> false

clone

import { yum } from '@drpiou/yum';

const base = yum.string().nullable(false);
const context = base.clone().nullable(true);

const result = context.validateSync(null);
// result[0] -> null
// result[1] -> undefined

const faulty = base.validateSync(null);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString canot be null.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'nullable'
// faulty[1].reasons[0].condition -> false

validate

import { yum, yumUtils } from '@drpiou/yum';

const context = yum.string().label('MyString');

try {
  const result = context.validate('');
  // result -> ''
} catch (error) {
  // Here we check if error is a YumError because `try/catch` will catch any Error type.
  if (yumUtils.isError(error)) {
    // error -> YumError
    // error.reasons[0].message -> 'The field MyString is required.'
    // error.reasons[0].label -> 'MyString'
    // error.reasons[0].type -> 'string'
    // error.reasons[0].rule -> 'required'
    // error.reasons[0].condition -> true
  }
}

validateSync

import { yum } from '@drpiou/yum';

const context = yum.string().label('MyString');

const result = context.validateSync('');
// result[0] -> ''
// result[1] -> undefined

const faulty = context.validateSync(null);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The field MyString is required.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'required'
// faulty[1].reasons[0].condition -> true

Types

mixed

The type mixed basically validates anything. For example, you can use it to validate nullable or required and to apply transform no matter the nature of the field.

import { yum } from '@drpiou/yum';

const context = yum.mixed().label('MyMixed');

const result = context.nullable(true).validateSync(null);
// result[0] -> null
// result[1] -> undefined

const faulty = context.nullable(false).validateSync(null);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The mixed field MyMixed cannot be null.'
// faulty[1].reasons[0].label -> 'MyMixed'
// faulty[1].reasons[0].type -> 'mixed'
// faulty[1].reasons[0].rule -> 'nullable'
// faulty[1].reasons[0].condition -> false

mixedOf

The type mixedOf validates multiple types. For example, you can use it to validate a field to be whether a string or a boolean.

import { yum } from '@drpiou/yum';

const context = yum.mixedOf([
  yum.string().label('MyString'),
  yum.date().label('MyDate'),
]);

const result = context.validateSync('a');
// result[0] -> 'a'
// result[1] -> undefined

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'
// faulty[1].reasons[1].message -> 'The date field MyDate must be of type date.'
// faulty[1].reasons[1].label -> 'MyDate'
// faulty[1].reasons[1].type -> 'date'
// faulty[1].reasons[1].rule -> 'type'

string

import { yum } from '@drpiou/yum';

const context = yum.string().label('MyString');

const result = context.validateSync('a');
// result[0] -> 'a'
// result[1] -> undefined

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

format

The format rule validates the string to be in a valid format.

import { yum } from '@drpiou/yum';

const context = yum.string().label('MyString').format('email');

const result = context.validateSync('my@email.com');
// result[0] -> 'my@email.com'
// result[1] -> undefined

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be in the valid "email" format.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'format'
// faulty[1].reasons[0].condition -> 'email'

include

The include rule validates the string to be in a set of values.

import { yum } from '@drpiou/yum';

const context = yum.string().include(['a', 'b']);

const result = context.validateSync('a');
// result[0] -> 'a'
// result[1] -> undefined

const faulty = context.validateSync('c');
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString ...'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'include'
// faulty[1].reasons[0].condition -> ['a', 'b']

range

The range rule validates the string length to be in range.

import { yum } from '@drpiou/yum';

const context = yum.string().range([1, 3]);

const result = context.validateSync('a');
// result[0] -> 'a'
// result[1] -> undefined

const faulty = context.validateSync('abcd');
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be greater or equal than 1 or less or equal than 3.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'range'
// faulty[1].reasons[0].condition -> [1, 3]

regex

The range rule validates the string to match a given RegExp.

import { yum } from '@drpiou/yum';

const context = yum.string().regex(/[a-z]/g);

const result = context.validateSync('a');
// result[0] -> 'a'
// result[1] -> undefined

const faulty = context.validateSync('A');
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be in the valid regex format.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'regex'
// faulty[1].reasons[0].condition -> /[a-z]/g

number

import { yum } from '@drpiou/yum';

const context = yum.number().label('MyNumber');

const result = context.validateSync(1);
// result[0] -> 1
// result[1] -> undefined

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The number field MyNumber must be of type number.'
// faulty[1].reasons[0].label -> 'MyNumber'
// faulty[1].reasons[0].type -> 'number'
// faulty[1].reasons[0].rule -> 'type'

include

The include rule validates the number to be in a set of values.

import { yum } from '@drpiou/yum';

const context = yum.number().label('MyNumber').include([1, 2]);

const result = context.validateSync(1);
// result[0] -> 1
// result[1] -> undefined

const faulty = context.validateSync(3);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The number field MyNumber ...'
// faulty[1].reasons[0].label -> 'MyNumber'
// faulty[1].reasons[0].type -> 'number'
// faulty[1].reasons[0].rule -> 'include'
// faulty[1].reasons[0].condition -> [1, 2]

range

The range rule validates the number to be in range.

import { yum } from '@drpiou/yum';

const context = yum.number().label('MyNumber').range([1, 3]);

const result = context.validateSync(1);
// result[0] -> 1
// result[1] -> undefined

const faulty = context.validateSync(4);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The number field MyNumber must be greater or equal than 1 or less or equal than 3.'
// faulty[1].reasons[0].label -> 'MyNumber'
// faulty[1].reasons[0].type -> 'number'
// faulty[1].reasons[0].rule -> 'range'
// faulty[1].reasons[0].condition -> [1, 3]

boolean

import { yum } from '@drpiou/yum';

const context = yum.boolean().label('MyBoolean');

const result = context.validateSync(true);
// result[0] -> true
// result[1] -> undefined

const faulty = context.validateSync('');
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The boolean field MyBoolean must be of type boolean.'
// faulty[1].reasons[0].label -> 'MyBoolean'
// faulty[1].reasons[0].type -> 'boolean'
// faulty[1].reasons[0].rule -> 'type'

date

import { yum } from '@drpiou/yum';

const context = yum.date().label('MyDate');

const result = context.validateSync(new Date());
// result[0] -> Date
// result[1] -> undefined

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The date field MyDate must be of type date.'
// faulty[1].reasons[0].label -> 'MyDate'
// faulty[1].reasons[0].type -> 'date'
// faulty[1].reasons[0].rule -> 'type'

include

The include rule validates the date to be in a set of values.

import { yum } from '@drpiou/yum';

const context = yum.date().label('MyDate').include([
  new Date('2023-01-01'),
  new Date('2023-01-02'),
]);

const result = context.validateSync(new Date('2023-01-01'));
// result[0] -> Date
// result[1] -> undefined

const faulty = context.validateSync(new Date('2023-01-03'));
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The date field MyDate ...'
// faulty[1].reasons[0].label -> 'MyDate'
// faulty[1].reasons[0].type -> 'date'
// faulty[1].reasons[0].rule -> 'include'
// faulty[1].reasons[0].condition -> [new Date('2023-01-01'), new Date('2023-01-02')]

range

The range rule validates the date to be in range.

Note that we need to give the timestamp of the date in the condition parameter.

import { yum } from '@drpiou/yum';

const context = yum.date().label('MyDate').range([
  new Date('2023-01-01').getTime(),
  new Date('2023-01-03').getTime(),
]);

const result = context.validateSync(new Date('2023-01-01'));
// result[0] -> Date
// result[1] -> undefined

const faulty = context.validateSync(new Date('2023-01-04'));
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The date field MyDate must be greater or equal than 1 or less or equal than 3.'
// faulty[1].reasons[0].label -> 'MyDate'
// faulty[1].reasons[0].type -> 'date'
// faulty[1].reasons[0].rule -> 'range'
// faulty[1].reasons[0].condition -> [1672527600, 1672614000]

array

import { yum } from '@drpiou/yum';

const context = yum.array().label('MyArray');

const result = context.validateSync(['a']);
// result[0] -> ['a']
// result[1] -> undefined

const faulty = context.validateSync(true);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The array field MyArray must be of type array.'
// faulty[1].reasons[0].label -> 'MyArray'
// faulty[1].reasons[0].type -> 'array'
// faulty[1].reasons[0].rule -> 'type'

of

The of rule validates the type of the array items.

import { yum } from '@drpiou/yum';

const base = yum.string().label('MyString');
const context = yum.array().of(base);

const result = context.validateSync(['a']);
// result[0] -> ['a']
// result[1] -> undefined

const faulty = context.validateSync([true]);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].path -> '0'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

include

The include rule validates the array items to be in a set of values.

Multiple arrays can be combined to validate one of the values group:

yum.array().include([['a', 'b']]);
// -> must be a mixed of 'a' and 'b'

yum.array().include([['a', 'b'], ['x', 'y']]);
// -> must be a mixed of 'a' and 'b'
// or must be a mixed of 'x' and 'y'

Example:

import { yum } from '@drpiou/yum';

const context = yum.array().label('MyArray').include([['a', 'b']]);

const result = context.validateSync(['a']);
// result[0] -> ['a']
// result[1] -> undefined

const faulty = context.validateSync(['c']);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The array field MyArray ...'
// faulty[1].reasons[0].path -> '0'
// faulty[1].reasons[0].label -> 'MyArray'
// faulty[1].reasons[0].type -> 'array'
// faulty[1].reasons[0].rule -> 'include'
// faulty[1].reasons[0].condition -> [['a', 'b']]

range

The range rule validates the array length to be in range.

import { yum } from '@drpiou/yum';

const context = yum.array().label('MyArray').range([1, 3]);

const result = context.validateSync(['a']);
// result[0] -> ['a']
// result[1] -> undefined

const faulty = context.validateSync(['a', 'b', 'c', 'd']);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The array field MyArray must be greater or equal than 1 or less or equal than 3.'
// faulty[1].reasons[0].path -> '0'
// faulty[1].reasons[0].label -> 'MyArray'
// faulty[1].reasons[0].type -> 'array'
// faulty[1].reasons[0].rule -> 'range'
// faulty[1].reasons[0].condition -> [1, 3]

object

shape

The shape rule validates the type of the object attributes.

import { yum } from '@drpiou/yum';

const context = yum.object().shape({ 
  a: yum.string().label('MyString'),
});

const result = context.validateSync({ a: 'a' });
// result[0] -> { a: 'a' }
// result[1] -> undefined

const faulty = context.validateSync({ a: true });
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].path -> 'a'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

Modules

The modules are the core components of Yum. In fact Yum objects (used as yum.string(). ...) are just a wrapper around these modules for chaining methods.

If Yum objects seems more convenient to use, the idea of exposing these modules is to extend Yum for a more advanced usage of this library.

Because Yum is still very experimental, many breaking change can occur.

Types

mixed

import { yumTypes } from '@drpiou/yum';

const { label, mixed, validateSync } = yumTypes;

const context = label('MyMixed', mixed());

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The mixed field MyMixed must be of type mixed.'
// faulty[1].reasons[0].label -> 'MyMixed'
// faulty[1].reasons[0].type -> 'mixed'
// faulty[1].reasons[0].rule -> 'type'

mixedOf

import { yumTypes } from '@drpiou/yum';

const { label, mixedOf, validateSync } = yumTypes;

const context = label('MyMixed', mixedOf());

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The mixed field MyMixed must be of type mixed.'
// faulty[1].reasons[0].label -> 'MyMixed'
// faulty[1].reasons[0].type -> 'mixed'
// faulty[1].reasons[0].rule -> 'type'

string

import { yumTypes } from '@drpiou/yum';

const { label, string, validateSync } = yumTypes;

const context = label('MyString', string());

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

number

import { yumTypes } from '@drpiou/yum';

const { label, number, validateSync } = yumTypes;

const context = label('MyNumber', number());

const result = validateSync(1, context);
// result[0] -> 1
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The number field MyNumber must be of type number.'
// faulty[1].reasons[0].label -> 'MyNumber'
// faulty[1].reasons[0].type -> 'number'
// faulty[1].reasons[0].rule -> 'type'

boolean

import { yumTypes } from '@drpiou/yum';

const { label, boolean, validateSync } = yumTypes;

const context = label('MyBoolean', boolean());

const result = validateSync(true, context);
// result[0] -> true
// result[1] -> undefined

const faulty = validateSync('', context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The boolean field MyBoolean must be of type boolean.'
// faulty[1].reasons[0].label -> 'MyBoolean'
// faulty[1].reasons[0].type -> 'boolean'
// faulty[1].reasons[0].rule -> 'type'

date

import { yumTypes } from '@drpiou/yum';

const { label, date, validateSync } = yumTypes;

const context = label('MyDate', date());

const result = validateSync(new Date(), context);
// result[0] -> Date
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The date field MyDate must be of type date.'
// faulty[1].reasons[0].label -> 'MyDate'
// faulty[1].reasons[0].type -> 'date'
// faulty[1].reasons[0].rule -> 'type'

array

import { yumTypes } from '@drpiou/yum';

const { label, array, validateSync } = yumTypes;

const context = label('MyArray', array());

const result = validateSync(['a'], context);
// result[0] -> ['a']
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The array field MyArray must be of type array.'
// faulty[1].reasons[0].label -> 'MyArray'
// faulty[1].reasons[0].type -> 'array'
// faulty[1].reasons[0].rule -> 'type'

object

import { yumTypes } from '@drpiou/yum';

const { label, object, validateSync } = yumTypes;

const context = label('MyObject', object());

const result = validateSync({ a: 'a' }, context);
// result[0] -> { a: 'a' }
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The object field MyObject must be of type object.'
// faulty[1].reasons[0].label -> 'MyObject'
// faulty[1].reasons[0].type -> 'object'
// faulty[1].reasons[0].rule -> 'type'

Rules

clone

import { yumTypes } from '@drpiou/yum';

const { clone, object, validateSync } = yumTypes;

const base = nullable(false, string());

const context = nullable(true, clone(base));

const result = validateSync(null, context);
// result[0] -> null
// result[1] -> undefined

const faulty = validateSync(null, base);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString canot be null.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'nullable'
// faulty[1].reasons[0].condition -> false

custom

import { yumRules, yumTypes } from '@drpiou/yum';

const { custom, label, string, validateSync } = yumTypes;

const context = custom('password', label('MyString', string()));

if (yumRules.hasCustom(context)) {
  if (context.custom === 'password') {
    //
  }
}

format

Valid formats are:

'date' | 'email' | 'ipv4' | 'ipv6' | 'phone' | 'url' | 'uuid'

The url condition has the following options:

yum.string().format('url', options as { 
  protocol?: string | string[];
});

The uuid condition has the following options:

yum.string().format('uuid', options as { 
  version?: '1' | '2' | '3' | '4' | '5' | 'all';
});

Examples:

import { yumTypes } from '@drpiou/yum';

const { format, label, string, validateSync } = yumTypes;

const context = format('email', label('MyString', string()));

const result = validateSync('my@email.com', context);
// result[0] -> 'my@email.com'
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be in the valid "email" format.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

include

import { yumTypes } from '@drpiou/yum';

const { include, label, string, validateSync } = yumTypes;

const context = include(['a', 'b'], label('MyString', string()));

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync('c', context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString ...'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

label

import { yumTypes } from '@drpiou/yum';

const { label, string, validateSync } = yumTypes;

const context = label('MyString', string());

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

merge

import { yumTypes } from '@drpiou/yum';

const { merge, nullable, string, validateSync } = yumTypes;

const base = nullable(true, string());
const context = merge(base, string());

const result = validateSync(null, context);
// result[0] -> null
// result[1] -> undefined

nullable

import { yumTypes } from '@drpiou/yum';

const { label, nullable, string, validateSync } = yumTypes;

const context = label('MyString', string());

const result = validateSync(null, nullable(true, context));
// result[0] -> null
// result[1] -> undefined

const faulty = validateSync(null, nullable(false, context));
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

of

import { yumTypes } from '@drpiou/yum';

const { array, label, of, string, validateSync } = yumTypes;

const context = of(label('MyString', string()), array());

const result = validateSync(['a'], context);
// result[0] -> ['a']
// result[1] -> undefined

const faulty = validateSync([true], context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].path -> '0'
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

or

import { yumTypes } from '@drpiou/yum';

const { date, label, mixed, or, string, validateSync } = yumTypes;

const context = or([label('MyString', string()), label('MyDate', date())], mixed());

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'
// faulty[1].reasons[1].message -> 'The date field MyDate must be of type date.'
// faulty[1].reasons[1].label -> 'MyDate'
// faulty[1].reasons[1].type -> 'date'
// faulty[1].reasons[1].rule -> 'type'

range

If min is null, then it checks only the maximum.

range([null, 3], context);
// -> less than 3 or equal

If max is undefined, then it checks only the minimum.

range([3], context);
// -> more than 3 or equal

If both min and max are given, it checks a range between min and max.

range([1, 3], context);
// -> more than 1 or equal and less than 3 or equal

If the condition is an array of conditions, then it checks multiple possible ranges.

range([[1, 3], [5, 8]], context);
// -> more than 1 or equal and less than 3 or equal
// or more than 5 or equal and less than 8 or equal

range([[null, 3], [5]], context);
// -> less than 3 or equal; or more than 5 or equal

Examples:

import { yumTypes } from '@drpiou/yum';

const { label, range, string, validateSync } = yumTypes;

const context = range([1, 3], label('MyString', string()));

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync('abcd', context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

regex

import { yumTypes } from '@drpiou/yum';

const { label, regex, string, validateSync } = yumTypes;

const context = regex(/[a-z]/g, label('MyString', string()));

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync('A', context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

required

import { yumTypes } from '@drpiou/yum';

const { label, required, string, validateSync } = yumTypes;

const context = label('MyString', string());

const result = validateSync(undefined, required(false, context));
// result[0] -> undefined
// result[1] -> undefined

const faulty = validateSync(undefined, required(true, context));
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The string field MyString must be of type string.'
// faulty[1].reasons[0].label -> 'MyString'
// faulty[1].reasons[0].type -> 'string'
// faulty[1].reasons[0].rule -> 'type'

shape

import { yumTypes } from '@drpiou/yum';

const { label, object, shape, validateSync } = yumTypes;

const context = shape({ a: 'a' }, label('MyObject', object()));

const result = validateSync('a', context);
// result[0] -> 'a'
// result[1] -> undefined

const faulty = validateSync(true, context);
// faulty[0] -> undefined
// faulty[1] -> YumError
// faulty[1].reasons[0].message -> 'The object field MyObject must be of type object.'
// faulty[1].reasons[0].label -> 'MyObject'
// faulty[1].reasons[0].type -> 'object'
// faulty[1].reasons[0].rule -> 'type'

transform

import { yumTypes } from '@drpiou/yum';

const { transform, string, validateSync } = yumTypes;

const context = transform((s) => String(s).toUpperCase(), string());

const result = validateSync('a', context);
// result[0] -> 'A'
// result[1] -> undefined

validate

import { yumTypes, yumUtils } from '@drpiou/yum';

const { label, string, validate } = yumTypes;

const context = label('MyString', string());

try {
  const result = validate('', context);
  // result -> ''
} catch (error) {
  // Here we check if error is a YumError because `try/catch` will catch any Error type.
  if (yumUtils.isError(error)) {
    // error -> YumError
    // error.reasons[0].message -> 'The field MyString is required.'
    // error.reasons[0].label -> 'MyString'
    // error.reasons[0].type -> 'string'
    // error.reasons[0].rule -> 'required'
    // error.reasons[0].condition -> true
  }
}

validateSync

The validateSync method will return an array.

import { yumTypes } from '@drpiou/yum';

const { string, validateSync } = yumTypes;

const context = string();

const result = validateSync('', context);

const value = result[0];
// -> `value` is the parsed value if the validation was successful
// or `undefined` if an error occurs

const error = result[1];
// -> `error` is `undefined` if the validation was successful
// or `YumError` if an error occurs

To type-check result in TypeScript, you need to test error first.

import { yumTypes } from '@drpiou/yum';

const { string, validateSync } = yumTypes;

const context = string();

const [result, error] = validateSync('', context);

// Here `result` is: string | undefined
// Here `error` is: undefined | YumError

if (error) {
  // Here `error` is: YumError
} else {
  // Here `result` is: 'string'
}