type-casting

Lightweight Library for cast and validating data. Used in https://www.npmjs.com/react-url-sync

Installing

npm install type-casting

Example

import Factory, { Type } from 'type-casting'

const user = Factory({
  id: Type.Int({ required: true }),
  name: Type.String,
  surname: Type.String({ required: true }),
  newsletter: Type.Bool({ default: true }),
  age: Type.Int,
})

// Print { id: 5, name: "abc", surname: "", newsletter: true }
console.log(user.cast({
  id: 5,
  name: 'abc'
}))

API

Library is exporting three modules:

• Factory
• Type
• ERROR

Factory methods

• cast(any) - cast to specified type
• validate(any) - validate specified type

Type.Array

const list = Type.Array(
  Type.Int({ default: 3, required: true })
).options({ default: [1, 2]})
// 5, 3, 6
list.cast([5, 'aaa', 6])
/*
{ 
  errors: [
    { error: 'NOT_A_NUMBER', index: 1 },
    { error: 'REQUIRED_BUT_EMPTY', index: 3 }
  ]
}
*/
list.validate([4, 'aa', 5, null])
list.cast() // [1, 2]

Type.Bool

const bool = Type.Bool({ default: true })
bool.cast() // true
bool.validate() // { 'error': 'NOT_A_BOOLEAN' }
bool.cast(true) // true
bool.cast(false) // false

Type.Float

const float = Type.Float()
float.cast('14.5') // 14.5
float.validate('abc') // { 'error': 'NOT_A_NUMBER' }
float.validate(500.43) // null

Type.Int

const int = Type.Int({ required: true })
int.cast() // 0
int.cast(55) // 55
int.validate('abcdef') // { 'error': 'NOT_A_NUMBER' }

Type.Object

import Factory, { Type } from 'type-casting'

const video = Factory({
  id: Type.Int({ required: true }),
  name: Type.String,
  length: Type.Int,
  authors: Type.Array(Type.Object({
    fullname: Type.String,
    address: Type.Object({
      city: Type.String,
      street: Type.String,
    }),
  })),
})

video.cast(...)
video.validate(...)

or types could be defined as:

import { Type } from 'type-casting'

Type.set('Address', Type.Object({
  city: Type.String,
  street: Type.String,
}))

Type.set('Author', Type.Object({
  fullname: Type.String,
  address: Type.Address,
}))

Type.set('Authors', Type.Array(Type.Author))

Type.set('Video', Type.Object({
  id: Type.Int({ required: true }),
  name: Type.String,
  length: Type.Int,
  authors: Type.Authors,
}))

Type.Video.cast(...)

Type.String

const string = Type.String({ required: true })
string.cast() // ''
string.cast(55) // '55'
string.cast('aaa') // 'aaa'
string.validate() // { error: ERROR.REQUIRED_BUT_EMPTY }

Type.set

Type.set('name', Type)

ERROR

NOT_A_NUMBER,
IS_EMPTY,
NOT_AN_ARRAY,
NOT_AN_OBJECT,
REQUIRED_BUT_EMPTY,
NOT_A_BOOLEAN,
NOT_VALID_TYPE,

Testing

npm run test

Building

npm run build