JS Object to JSON Schema Inferrer

A ts based, fully typed inferrer which can convert js object to JSON schema. The schema is based on draft-07 and supports customize configs.

Install

 npm install js-json-schema-inferrer

Basic Usage

import { JsonSchemaInferrer } from 'js-json-schema-inferrer'

const sourceObject = {
  name: "cest jun",
  age: 21,
  favoriteFoods: ["toast", "dumplings"]
}

const schema = JsonSchemaInferrer(sourceObject)

Configs

Inferrer supports customizing configs to control the format and elements of the inferred result.

JsonSchemaInferrer(input: any, config?: InferrerConfig)

interface InferrerConfig {
  type: boolean
  string: StringOptions
  object: ObjectOptions
  array: ArrayOptions
  common: CommonOptions
}

Default config:

const defaultConfig: InferrerConfig = {
  type: true,
  string: {
    detectFormat: false
  },
  object: {},
  array: {
    arrayInferMode: 'first'
  },
  common: {}
}

StringOptions

• detectFormat: boolean : if true, the inferrer can detect each string's format regexp.

ObjectOptions

• required: boolean: if true, make every property in the object required.
• allowAdditionalProperties: boolean | undefined: control if this object allows additional properties besides listed ones.

ArrayOptions

• arrayInferMode: 'first' | 'tuple':
  • 'first' means a kind of list validation, it uses the first item of the array to validate all the items.
  • tuple means tuple validation. All the items in the array have their own validation schema.
• allowAdditionalItems: boolean | undefined: control if this array allows additional properties.
• uniqueItems: boolean | undefined: control if this array's items are unique.

CommonConfig

• title: boolean: if true, display the title of each instance. Default 'The ${name} schema
• description: boolean: if true, display the description of each instance. Default An explanation about the purpose of this instance.
• default: boolean: if true, make the source object's values be each instance's default value.
• examples: boolean: if true, make origin values be example value.
• const: boolean: if true, make origin values be const.
• enum: boolean: if true, make origin values be the first element of enums.

TODOs

1. Configure id inferring.
2. Add more arrayInferMode, eg: 'anyOf'
3. Update the string formats Regexps to suit draft-07
4. Add tests.
5. Add badges ;)