Export Types

Rhino includes a Rails command that generates TypeScript interfaces from your registered models. It introspects the database schema, builds an OpenAPI 3.0 spec internally, and runs openapi-typescript to produce a .d.ts file.

Requirements

The command runs npx openapi-typescript under the hood, so Node.js must be available on the machine where you run the command.

Usage

terminal

rails rhino:export_types

This introspects all registered models from Rhino.config.models, reads their database columns via columns_hash, and writes TypeScript interfaces to the configured output paths.

Command Flags

Flag	Default	Description
--output	(none)	Explicit output file path. Overrides config/env paths.

Examples

terminal

# Write to configured paths (RHINO_CLIENT_PATH / RHINO_MOBILE_PATH)
rails rhino:export_types

# Write to a specific file
rails rhino:export_types --output=tmp/rhino.d.ts

Configuration

Set the output paths via environment variables:

.env

RHINO_CLIENT_PATH=../client
RHINO_MOBILE_PATH=../mobile

Or in the Rhino configuration block:

config/initializers/rhino.rb

Rhino.configure do |c|
  c.client_path = ENV['RHINO_CLIENT_PATH']
  c.mobile_path = ENV['RHINO_MOBILE_PATH']
end

When both paths are set, the command writes to both:

• {client_path}/src/types/rhino.d.ts
• {mobile_path}/src/types/rhino.d.ts

The --output flag overrides both and writes to a single explicit path.

Generated Output

The command generates one interface per model. All fields are optional because Rhino's policy system controls which attributes are visible per user/role at runtime.

src/types/rhino.d.ts

export interface Post {
  id?: number;
  title?: string;
  content?: string;
  is_published?: boolean;
  blog_id?: number;
  created_at?: string;
  updated_at?: string;
  deleted_at?: string | null;
}

Type Mapping

ActiveRecord Type	TypeScript Type
:integer, :bigint	number
:decimal, :float	number
:boolean	boolean
:datetime, :date, :time	string
:json, :jsonb	Record<string, unknown>
:string, :text	string
Nullable columns	adds | null

Using Generated Types

Import the generated types and pass them as generics to Rhino hooks:

src/components/PostsList.tsx

import type { Post } from '../types/rhino';
import { useModelIndex, useModelStore, useModelUpdate } from '@rhino-dev/rhino-react';

// Typed list — data.data is Post[]
const { data } = useModelIndex<Post>('posts', { sort: '-created_at' });

// Typed create — mutate accepts Partial<Post>
const store = useModelStore<Post>('posts');
store.mutate({ title: 'Hello', content: 'World' });

// Typed update — mutate accepts { id, data: Partial<Post> }
const update = useModelUpdate<Post>('posts');
update.mutate({ id: 1, data: { title: 'Updated' } });

Why all fields optional?

Rhino's policy system (permitted_attributes_for_show, hidden_attributes_for_show) dynamically controls which fields appear in API responses based on the authenticated user's role and custom logic. The generated types represent the union of all possible fields, not a guarantee of which fields will be present in any given response.

Workflow

1. Define your models and run migrations
2. Run rails rhino:export_types
3. Import the generated types in your React/React Native code
4. Re-run the command whenever you change your database schema