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Package detail

type

medikoo41.8mISC2.7.3TypeScript support: included

Runtime validation and processing of JavaScript types

type, coercion

readme

Build status Tests coverage npm version

type

Runtime validation and processing of JavaScript types

  • Respects language nature and acknowledges its quirks
  • Allows coercion in restricted forms (rejects clearly invalid input, normalizes permissible type deviations)
  • No transpilation implied, written to work in all ECMAScript 3+ engines

Use case

Validate arguments input in public API endpoints.

For validation of more sophisticated input structures (as deeply nested configuration objects) it's recommended to consider more powerful schema based utlities (as AJV or @hapi/joi)

Example usage

Bulletproof input arguments normalization and validation:

const ensureString        = require('type/string/ensure')
    , ensureDate          = require('type/date/ensure')
    , ensureNaturalNumber = require('type/natural-number/ensure')
    , isObject            = require('type/object/is');

module.exports = (path, options = { min: 0 }) {
  path = ensureString(path, { errorMessage: "%v is not a path" });
  if (!isObject(options)) options = {};
  const min = ensureNaturalNumber(options.min, { default: 0 })
      , max = ensureNaturalNumber(options.max, { isOptional: true })
      , startTime = ensureDate(options.startTime, { isOptional: true });

  // ...logic
};

Installation

npm install type

Utilities

Aside of general ensure validation util, following kind of utilities for recognized JavaScript types are provided:

*/coerce

Restricted coercion into primitive type. Returns coerced value or null if value is not coercible per rules.

*/is

Object type/kind confirmation, returns either true or false.

*/ensure

Value validation. Returns input value (in primitive cases possibly coerced) or if value doesn't meet the constraints throws TypeError .

Each */ensure utility, accepts following options (eventually passed with second argument):

  • isOptional - Makes null or undefined accepted as valid value. In such case instead of TypeError being thrown, null is returned.
  • default - A value to be returned if null or undefined is passed as an input value.
  • errorMessage - Custom error message. Following placeholders can be used:
    • %v - To be replaced with short string representation of invalid value
    • %n - To be replaced with meaninfgul name (to be passed with name option) of validated value. Not effective if name option is not present
  • errorCode - Eventual error code to be exposed on .code error property
  • name - Meaningful name for validated value, to be used in error message, assuming it contains %n placeholder
  • Error - Alternative error constructor to be used (defaults to TypeError)

Index

General utils:

Type specific utils:

Tests

$ npm test

Security contact information

To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure.

changelog

Changelog

All notable changes to this project will be documented in this file. See standard-version for commit guidelines.

2.7.3 (2024-05-30)

Maintenance Improvements

  • Add security vulnerability policy (a28cc58)
  • Prettify (aaa9256)
  • Upgrade prettier-elastic to v3 (7f10b2c)

2.7.2 (2022-08-05)

Maintenance Improvements

2.7.1 (2022-08-04)

Maintenance Improvements

  • TS: Fix support for isOptional in ensure options (#7) (320f89b) (Marco)

2.7.0 (2022-08-03)

Features

  • BigInt.coerce and BigInt.ensure (e49ad78)

2.6.1 (2022-07-29)

Maintenance Improvements

2.6.0 (2022-02-02)

Features

  • constructor validation utils (74b99bb)

2.5.0 (2021-03-08)

Features

  • errorCode option for ensure* utils (777a1f2)

2.4.0 (2021-03-08)

Features

  • set/is and set/ensure utils (083ec23)

2.3.0 (2021-02-16)

Features

  • map/is and map/ensure utils (aafd1cb)

2.2.0 (2021-02-11)

Features

  • Support ensureItem option in array/ensure (8f74973)

2.1.0 (2020-08-21)

Features

  • ensure util for cumulated input validation (814c5a8)
  • Provide an alternative error message with options.name (c7751c0)
  • Support %n (meaningful name) token in error message resolver (b0f374e)
  • Support min validation for natural numbers (e703512)
  • Support custom Error constructors (c6ecb90)

Bug Fixes

  • Fix typo in error message (2735533)

2.0.0 (2019-10-10)

Features

  • allowedKeys option for plain-object/ensure (f81e72e)
  • ensurePropertyValue option for plain-object/ensure (c5ff8fb)
  • Replace coerceItem with ensureItem option in iterable/ensure (721494f)
  • Seclude lib/resolve-error-message (12636d9)
  • Validate options.ensureItem in iterable/ensure (78da6c1)

BREAKING CHANGES

  • iterable/ensure no longer supports coerceItem option. Instead ensureItem was introduced

1.2.0 (2019-09-20)

Bug Fixes

  • Improve error message so it's not confusing (97cd6b9)

Features

  • 'coerceItem' option for iterable/ensure (0818860)

1.1.0 (2019-09-20)

Features

  • denyEmpty option for iterables validation (301d071)

1.0.3 (2019-08-06)

Bug Fixes

  • Recognize custom built ES5 era errors (6462fac)

1.0.2 (2019-08-06)

Bug Fixes

  • Recognize host errors (e.g. DOMException) (96ef399)

1.0.1 (2019-04-08)

1.0.0 (2019-04-05)

Bug Fixes

  • ensure 'is' functions can't crash (59ceb78)

Features