json-valid-3k

Validate or generate JSON-like structures with schemas

Usage - simple

import { validate } from 'json-valid-3k'

const data = {
  arr: [],
  num: 3,
  str: 'High quality string',
}
const schema = {
  arr: 'Array',
  num: 'Number',
  str: 'String',
}

const test = validate(data, schema)

Validation response object

{
  valid: boolean
  tree: { YOUR_OBJECT_PROPS / ERRORS },
  errors: Map<K, V>  // A flat list displaying the exact depth position of each failed value
  dropped: Map<K, V> // Shows the errors for silently dropped items (silentDrop: true)
}

The tree object stores your output. It contains the relevant value OR error for each key:value pair. Discards everything not in the schema. The idea is that if you really care about your data integrity, than there's not reason not to use it as opposed to dragging everything esle from your source object.

Usage - expanded

import { validate } from 'json-valid-3k'
// OR
// const { validate } = require('json-valid-3k')

const CFG_SIMPLE = {
  arr: [],                            // 01. Array
  boo: true,                          // 02. Boolean
  elm: document.createElement('div'), // 03. Element
  fun: () => {},                      // 04. Function
  num: 3,                             // 05. Number
  obj: {},                            // 06. Object
  str: 'High quality string',         // 07. String
  url: 'https://some.place.com',      // 08. URL
  mail: '[email protected]',                      // 09. ValidEmail
  ip: '192.168.0.251',                // 10. ValidIP
  def: null,                          // 11. null
}
const SCHEMA_SIMPLE = {
  arr: 'Array',       // { type: 'Array' },
  boo: 'Boolean',     // { type: 'Boolean' },
  elm: 'Element',     // { type: 'Element' },
  fun: 'Function',    // { type: 'Function' },
  num: 'Number',      // { type: 'Number' },
  obj: 'Object',      // { type: 'Object' },
  str: 'String',      // { type: 'String' },
  url: 'URL',         // { type: 'URL' },
  mail: 'ValidEmail', // { type: 'ValidEmail' },
  ip: 'ValidIP',      // { type: 'ValidIP' },
  def: null,          // { type: null },
}

const test = validate(CFG_SIMPLE, SCHEMA_SIMPLE)

Types

Predefined Types

01. Array
02. Boolean
03. Element
04. Function
05. Number
06. Object
07. String
08. URL
09. ValidEmail
10. ValidIP

Custom types

Adding custom types is simple. This is exactly what json-validate-3k is using internally for its predefined types.

import { validate, types } from 'json-valid-3k'

types.set('LongString', (v) => {
    return typeof v === 'string' && v.length > 255
})

Custom functions as rules

Sometimes even custom type aren't enough and we have to reach for something more.

import { validate } from 'json-valid-3k'

const dataObject = {
  abc: 'AaBbCc',
  arr: [1, 2, 3, 4, 5]
}
const dataSchema = {
  abc: 'String',
  arr: (value, data, schema) => {
    return Array.isArray(value) && value.length > 3
  }
}

// Your validation object
const { valid, tree, errors, dropped } = validate(dataObject, dataSchema)

Multiple possible types per value

Every value can be targeted via one or more rule types

const SCHEMA_MULTIPLE = {
  aaa: 'Array',
  bbb: ['Array', 'Number'],
  ccc: ['String', 'Object', null]
}

Additional Schema Options

{
  // ...Some props
  optional: Boolean,
  default: 'Something', // Has to match the type. NOT applied when "optional" is "true"
  allowEmpty: Boolean,  // Default value is true. Using false fails empty Array/Object/String values
  silentDrop: Boolean,  // Default value is false. Using true drops failed items without raising the alarm
}

Usage - deep nesting

import { validate } from 'json-valid-3k'

const a_data = {
  a: 'kisk',
  b: {
    duck: 123,
    bb: 123,
    xx: {
      q: [
        { qub: 456 },
        { qub: 789 },
        { qub: 'I am wrong, hehe' },
        null,
        undefined,
        { irrelevant: 'prop' },
        { qub: 111 },
      ]
    },
    yy: {
      hello: 'World',
    },
  },
  c: ['Dingo'],
  d: () => ({}),
}
const a_schema = {
  a: { type: 'String', optional: true },
  c: { type: 'Array', optional: false },
  b: {
    type: 'Object',
    optional: true,
    props: {
      duck: { type: 'String', optional: true },
      bb: { type: 'Number', optional: false },
      xx: {
        type: 'Object',
        props: {
          q: {
            type: 'Array',
            children: {
              type: 'Object',
              props: { qub: { type: 'Number' } },
            },
          },
        },
      },
      yy: {
        type: 'Object',
        props: {
          hello: { type: 'String' },
          aaa: { type: 'Boolean', default: false },
          bbb: { type: 'Boolean', default: true },
          ccc: { type: null, default: null },
          ddd: { type: null, default: undefined },
          eee: { type: 'String', default: 'This will show up', },
          fff: { type: 'String', default: 'This will NOT show up because it is optional', optional: true },
        },
      },
    },
  },
  d: { type: 'Function' }
}

const test = validate(a_data, a_schema)
test = {
  valid: false, // OR true
  tree: {
    a: "kisk"
    b:
    bb: 123
    duck: "ERROR: Value [123] does not match type [String]"
    xx: {
      q: Array(7) [
        0: {qub: 456}
        1: {qub: 789}
        2: {qub: "ERROR: Value ["I am wrong, hehe"] does not match type [Number]"}
        3: "ERROR: Value [null] does not match type [Object]"
        4: "ERROR: Value [undefined] does not match type [Object]"
        5: {qub: "ERROR: Value [undefined] does not match type [Number]"}
        6: {qub: 111}
      ]
    }
    yy: {
      aaa: false
      bbb: true
      ccc: null
      ddd: "ERROR: Value [undefined] does not match type [null]"
      eee: "This will show up"
      hello: "World"
    }
    c: ["Dingo"]
    d: () => ({})
  }, 
}