hono-zod-openapi

Type-safe OpenAPI middleware for Hono. Just add a middleware - no refactoring needed.

See full documentation here

Installation

npm install hono-zod-openapi

Or, if you prefer JSR:

jsr add @paolostyle/hono-zod-openapi

Quick Example

import { Hono } from 'hono';
import * as z from 'zod';
import { createOpenApiDocument, openApi } from 'hono-zod-openapi';

const app = new Hono().get(
  '/user',
  openApi({
    tags: ['User'],
    responses: {
      200: z.object({ hi: z.string() }),
    },
    request: {
      query: z.object({ id: z.string() }),
    },
  }),
  (c) => {
    const { id } = c.req.valid('query');
    return c.var.res(200, { hi: id });
  },
);

createOpenApiDocument(app, {
  info: {
    title: 'Example API',
    version: '1.0.0',
  },
});

Why This Library?

Hono provides a 3rd-party middleware in their middleware monorepo, which probably works alright, however the issue with that package is that it forces you to write your code in a different manner than you normally would in Hono. Refactoring the app becomes a significant hassle.

This library provides an openApi middleware instead, which you can easily add to your existing codebase, and a createOpenApiDocument function, which will generate an OpenAPI-compliant JSON document and serve it under /doc route of your app (it's configurable, don't worry).

For detailed usage, recipes, API reference, and more, see the full documentation.

License

MIT