dsl-schema

So I herd U liek JSON Schema!

dsl-schema provides simple, yet powerful API for building up your JSON Schemas based on examples you provide.

import like from 'dsl-schema'
 
const mySchema = like({
  foo: 'some string',
  baz: ['yup'],
  // Can be nested for more fine-grained control!
  here: like.Enum('come dat boi', 'I come'),
})
 
// true
ajv.validate(mySchema, {
  foo: 'bar',
  baz: ['fizz buz'],
  here: 'I come',
})
 
// false
ajv.validate(mySchema, {
  not: 'valid',
})

Getting started

npm install dsl-schema # OR 
yarn add dsl-schema

import like from 'dsl-schema'
const schema = like(1337)

Docs

like

like: (example: any) => Schema

• For object like example it builds up a Record of its properties
• For array like example it builds up a Tuple of its elements
• For primitive example it tries to guess the best schema for it:
  • NULL for null and undefined
  • BOOL for boolean
  • Int for number when it pass Number.isInteger
  • Float for number when it doesn't
  • one of the Constants with fallback to Str for string. Decision is based on very loose RegExps for ISO 8601 date-time, URL, e-mail, IPv4, IPv6 and UUID

like.Str

Str: (opts: string) => Schema

Min and max length can be specified using opts

• Str('10 > len')
• Str('3 < length')
• Str('3 < len <=10')

like.Float

Float: (opts: string) => Schema

Min, max, and multipleOf can be specified using opts

• Float('1.3 < x')
• Float('1.3 < x <= 6')
• Float('n*0.1')
• Float('1.3 < x <= 6, n*2.6')

like.Int

Int: (opts: string) => Schema

See Float

like.req

req: (s: Schema) => TaggedSchema

Tags schema as required

like.opt

req: (s: Schema) => TaggedSchema

Tags schema as optional

like.Tuple

Tuple: (...items: TaggedSchema[]) => Schema

like.Record

Record: (props: { [key: string]: TaggedSchema }) => Schema

like.Dict

Dict: (opts: string, itemsType: Schema) => Schema
Dict: (itemsType: Schema) => Schema

Size of the dictionary can be specified using opts

• Dict('size <= 10')
• Dict('length > 10')
• Dict('30 > len > 10')

like.List

List: (opts: string, itemsType: Schema) => Schema
List: (itemsType: Schema) => Schema

See Dict. Can also specify uniqueness

• List('unique')
• List('uniq, len < 30')

like.Enum

Enum: (...items: (null | boolean | number | string)[]) => Schema

Elements of the items must be unique

like.AllOf

AllOf: (...schemas: Schema[]) => Schema

like.AnyOf

AnyOf: (...schemas: Schema[]) => Schema

like.OneOf

OneOf: (...schemas: Schema[]) => Schema

like.Not

Not: (schema: Schema) => Schema

Constant schemas

• ANY
• BOOL
• NULL
• DATE
• TIME
• DATE_TIME
• URI
• URI_REFERENCE
• URI_TEMPLATE
• URL
• EMAIL
• HOSTNAME
• IPV4
• IPV6
• REGEX
• UUID