@superfunctions/http-fastify

Fastify adapter for @superfunctions/http - Use framework-agnostic routers with Fastify.

Installation

``bash
npm install @superfunctions/http @superfunctions/http-fastify fastify
`

Quick Start

`typescript
import Fastify from 'fastify';
import { createRouter } from '@superfunctions/http';
import { toFastify } from '@superfunctions/http-fastify';

// Define your router (framework-agnostic)
const apiRouter = createRouter({
routes: [
{
method: 'GET',
path: '/users/:id',
handler: async (req, ctx) => {
return Response.json({ id: ctx.params.id });
},
},
],
});

// Use with Fastify
const fastify = Fastify();
await fastify.register(toFastify(apiRouter), { prefix: '/api' });
await fastify.listen({ port: 3000 });
`

API

$3

Converts a @superfunctions/http router to a Fastify plugin.

Parameters:
- router: Router instance from @superfunctions/http

Returns: FastifyPluginAsync

Example:
`typescript
import { toFastify } from '@superfunctions/http-fastify';

await fastify.register(toFastify(myRouter), {
prefix: '/api'
});
`

Usage Examples

$3

`typescript
import Fastify from 'fastify';
import { toFastify } from '@superfunctions/http-fastify';

const fastify = Fastify();

// Register with prefix
await fastify.register(toFastify(apiRouter), {
prefix: '/api/v1'
});

// Routes accessible at: /api/v1/*
await fastify.listen({ port: 3000 });
`

$3

`typescript
import { createRouter } from '@superfunctions/http';
import { toFastify } from '@superfunctions/http-fastify';

const router = createRouter({
middleware: [
async (req, ctx, next) => {
// Auth middleware
const token = req.headers.get('Authorization');
if (!token) {
return Response.json({ error: 'Unauthorized' }, { status: 401 });
}
return next();
},
],
routes: [
{
method: 'GET',
path: '/protected',
handler: async () => Response.json({ data: 'secret' }),
},
],
});

await fastify.register(toFastify(router), { prefix: '/api' });
`

$3

`typescript
interface AppContext {
db: Database;
}

const router = createRouter({
context: { db: myDatabase },
routes: [
{
method: 'GET',
path: '/users',
handler: async (req, ctx) => {
const users = await ctx.db.findMany({ model: 'users' });
return Response.json(users);
},
},
],
});

await fastify.register(toFastify(router), { prefix: '/api' });
`

$3

`typescript
const usersRouter = createRouter({ routes: [/ user routes /] });
const postsRouter = createRouter({ routes: [/ post routes /] });

await fastify.register(toFastify(usersRouter), { prefix: '/api/users' });
await fastify.register(toFastify(postsRouter), { prefix: '/api/posts' });
`

$3

You can combine with other Fastify plugins:

`typescript
import Fastify from 'fastify';
import fastifyCors from '@fastify/cors';
import { toFastify } from '@superfunctions/http-fastify';

const fastify = Fastify();

// Register CORS plugin
await fastify.register(fastifyCors, {
origin: 'https://example.com'
});

// Register your router
await fastify.register(toFastify(apiRouter), { prefix: '/api' });

await fastify.listen({ port: 3000 });
`

Important Notes

$3

The adapter returns a Fastify plugin that must be registered with await fastify.register():

`typescript
// ✅ Correct - await registration
await fastify.register(toFastify(router));

// ❌ Incorrect - missing await
fastify.register(toFastify(router));
`

$3

The adapter automatically handles the prefix from plugin options:

`typescript
const router = createRouter({
routes: [
{ method: 'GET', path: '/hello', handler: () => Response.json({ msg: 'hi' }) }
]
});

// Route accessible at: /api/hello
await fastify.register(toFastify(router), { prefix: '/api' });
`

$3

Fastify automatically serializes JSON responses. The adapter handles this by:
- Parsing JSON from Web Response
- Sending parsed objects to Fastify
- Letting Fastify handle serialization

$3

Fastify automatically parses JSON and form data. The adapter accesses the parsed body via request.body.

$3

Use Fastify's built-in inject method for testing:

`typescript
const response = await fastify.inject({
method: 'GET',
url: '/api/hello'
});

expect(response.statusCode).toBe(200);
expect(response.json()).toEqual({ message: 'Hello' });
`

TypeScript

Full TypeScript support with proper types:

`typescript
import type { Router } from '@superfunctions/http';
import type { FastifyPluginAsync } from 'fastify';

const myRouter: Router = createRouter({ routes: [...] });
const plugin: FastifyPluginAsync = toFastify(myRouter);

await fastify.register(plugin, { prefix: '/api' });
``

Performance

The adapter is designed for minimal overhead:
- Uses catch-all route to delegate to the router
- Minimal request/response translation
- Leverages Fastify's fast JSON serialization

Compatibility

- Fastify 4.x ✅
- Fastify 5.x ✅

License

MIT