Script to generate AJV compatible JSON Schema typescript object modules from an OpenAPI 3 schema.

[waynesbrain]

I was searching for a way to re-use my OpenAPI component schemas for validating forms with react-hook-form and AJV.

I found nothing so I created this script - https://gist.github.com/waynesbrain/6f8b423b865efe67b1deb46023a83d94

Disclaimer: This is not the greatest script, I haven't tested it with recursive $refs or with very complex OpenAPI schemas. It was partly written by Claude 3.7 Sonnet.

It converts OpenAPI PUT/POST requestBody schemas to JSON Schemas with referenced definitions, ready for use with AJV, something like this:

import type { operations } from "../api.gen";

export type Body = Required<
  operations["operationId"]
>["requestBody"]["content"]["application/json"];

export const Body = {
  type: "object",
  properties: {
    a: { type: "string" },
    b: { type: "number" },
    c: { $ref: "#/definitions/Point" }
  },
  definitions: {
    Point: {
       type: "object",
       properties: {
          x: { type: "number" },
          y: { type: "number" },
       },
       required: ["x", "y"]
     },
  },
} as const;