Fastify

Supports Fastify ^5.0.0.

Import undevice from undevice/fastify and register await app.register(undevice()) before your routes. Each request gets a fresh frozen result in request.undevice. Importing the adapter automatically types built-in flags in route handlers.

Setup

import Fastify from 'fastify';
import { undevice } from 'undevice/fastify';

const app = Fastify();
await app.register(undevice());

app.get('/device', async (request, reply) => {
  request.undevice.isMobile; // boolean
  return reply.send(request.undevice);
});

Custom flag types

Extend UndeviceCustomFlags to type custom flags in Fastify routes.

Manual declarations

Declare custom flag names with the type boolean. Include only flags passed to the plugin configuration:

undevice.d.ts

import 'undevice/fastify';

declare module 'undevice/fastify' {
  interface UndeviceCustomFlags {
    isCustomFlag: boolean;
    isAnotherCustomFlag: boolean;
  }
}

Inference from a plugin

UndevicePluginFlags<typeof undevicePlugin> extracts custom flag types from the configured plugin:

app.ts

import Fastify from 'fastify';
import { undevice } from 'undevice/fastify';

const app = Fastify();
export const undevicePlugin = undevice({
  isBot: ['bot'],
  isRawClient: ['curl', 'wget'],
});

await app.register(undevicePlugin);

app.get('/device', async (request, reply) => {
  request.undevice.isMobile;    // boolean
  request.undevice.isBot;       // boolean
  request.undevice.isRawClient; // boolean
  return reply.send(request.undevice);
});

undevice.d.ts

import type { UndevicePluginFlags } from 'undevice/fastify';
import type { undevicePlugin } from './app.js';

type Flags = UndevicePluginFlags<typeof undevicePlugin>;

declare module 'undevice/fastify' {
  interface UndeviceCustomFlags extends Flags {}
}

Include undevice.d.ts in the application's TypeScript project. The augmentation applies to all Fastify routes in that project.