Typed RPC App Recipe

This recipe shows how to make the server route contract visible to client code without generating a separate SDK first.

Server

import { createOrva } from 'orvajs';
import { validator } from 'orvajs/validator';

export const app = createOrva()
  .get('/posts', (c) => c.json([{ id: 1, title: 'Post 1' }]))
  .get('/posts/:id', (c) => c.json({ id: c.params.id, title: 'Post details' }))
  .post(
    '/users',
    validator('json', (value: any) => ({
      name: String(value.name ?? ''),
      age: Number(value.age ?? 0),
    })),
    (c) => c.json({ ok: true, user: c.valid('json') }, 201),
  );

Client

import { createRPC } from 'orvajs/rpc';
import { app } from './server';

const rpc = createRPC<typeof app>({
  baseURL: 'https://api.example.com',
});

const posts = await rpc.posts.$get();
const list = await posts.json();

const post = await rpc.posts[':id'].$get({
  param: { id: '123' },
});
const detail = await post.json();

await rpc.users.$post({
  body: {
    name: 'Ada',
    age: 20,
  },
});

What gets inferred

• list becomes { id: number; title: string }[]
• detail becomes { id: string; title: string }
• rpc.users.$post() expects body as { name: string; age: number }

When to use this pattern

• frontend and backend live in the same monorepo
• internal tools want typed clients quickly
• you want RPC ergonomics without hiding the HTTP shape

Read next

• Type Flow
• RPC
• OpenAPI