objection-ts-schema

This is a small library for providing better typescript integration with objection.js.

Strictly speaking this isn't really objection - specific. The gist of the library is that you use the addSchema - decorator on typescript class fields and it generates a JSON schema - object for the class constructor.

This matches exactly how objection validates models, by having static jsonSchema - field that is used for json validation.

setup

installation:

  npm install objection-ts-schema

The project this is used in requires few typescript settings to enable decorators and for emitting reflection metada.

{
  "compilerOptions": {
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true
  }
}

usage examples

Here's an objection model use-case:

import {addSchema} from 'objection-ts-schema'

class Person extends Model {
  @addSchema(true) name: string
  @addSchema(false) age?: number
}

addSchema is defined as follows

  function addSchema(required?: boolean): void

The required parameter is needed to inform the decorator whether the field is optional or not. As far as we know, reflect-metadata does not provide a way to determine union types or optional fields.

disclaimer

While this is a fairly simple library, it has not been tested comprehensively. Use with care.