@naturalcycles/json-schema-lib

JSON schema to/from TypeScript parser/generator

Allows to generate JSON Schema from a set of Typescript files with Interfaces (also Types and Enums).

Also, to generate Typescript files from JSON schemas (reverse).

Status: experimental! Everything is subject to change!

Example

Install json-schema-lib as your devDependency:

yarn add -D @naturacycles/json-schema-lib

Define a jsonSchemaGenerator.cfg.js in the root of you project:

module.exports = {
  paths: ['src/types/*.ts'],
  outputDir: 'resources/schemas',
}

Config says to scan all *.ts files in src/types, parse them, generate JSON schemas, write them into resources/schemas folder.

Similar projects

• https://github.com/YousefED/typescript-json-schema
• https://github.com/vega/ts-json-schema-generator

Develop

Typescript AST debugging: https://ts-ast-viewer.com/

Supported

• Schemas from:
  • Interfaces
  • Types
  • Enums
  • Classes
• string, number, boolean
• Literal types, e.g someString, 15, true
• null type
• object, array
• tuple
• enum (string and number values)
• optional/required properties
• Union types (|), Intersections (&), extends
• jsdoc @validationType (e.g. integer)
• Type references, e.g. p: Person (where Person is defined elsewhere, can be in another file)
• Parsing a list of files (not necessary for all types to be in 1 file)
• Partial, Required
• Record<A, B>
• Indexed properties ({ [name: string]: string })
• StringMap (aka Dictionary)
• jsdoc tags:
  • validationType to override type, e.g. @validationType integer
  • General: deprecated, readOnly, writeOnly, default
  • String: pattern, format, minLength, maxLength
  • Number: multipleOf, minimum, exclusiveMinimum, maximum, exclusiveMaximum
  • Object: additionalProperties, minProperties, maxProperties
  • Array: minItems, maxItems, uniqueItems
  • Schema composition: if, then, else, dependencies, dependentRequired, dependentSchemas

Currently NOT supported

• Omit, Pick
• Generic interfaces, e.g. interface MyType<T> { current: T, future: T }
• typeof
• keyof
• Conditional types