nuxt-better-auth-utils

Nuxt module for Better Auth — full lifecycle integration with auto-wired handler, SSR, session state, and typed server/client APIs.

Features

• Auto-registered API handler (/api/auth/**)
• SSR session pre-fetch — session available on first render
• useAuth() composable with reactive session, user, loggedIn, and raw client access
• useServerAuth() server utility with requireSession, getSession, and raw auth instance
• auth route middleware for protecting pages
• Auth type export via #nuxt-better-auth-utils for typed client plugins
• Session signal listener for cross-tab sync
• Built-in components: AuthOnly, GuestOnly, AuthUserButton, AuthTeamSwitcher
• Zero opinions on database adapter, plugins, or auth strategy

Setup

npx nuxi module add nuxt-better-auth-utils

Add to nuxt.config.ts:

export default defineNuxtConfig({
  modules: ['nuxt-better-auth-utils'],
})

Set BETTER_AUTH_SECRET in your .env (or NUXT_SECRET).

Configuration

Server Config — server/auth.server.config.ts

Place this file in the server/ directory so that server auto-imports (e.g. useDrizzle()) are available.

Standard Better Auth options. The module auto-injects secret.

import { drizzleAdapter } from 'better-auth/adapters/drizzle'
import { organization } from 'better-auth/plugins'

export default defineAuthConfig({
  database: drizzleAdapter(db, { provider: 'pg' }),
  emailAndPassword: { enabled: true },
  plugins: [organization()],
})

Supports factory functions for deferred access to runtime utilities:

export default defineAuthConfig(() => {
  const db = useDrizzle()
  return {
    database: drizzleAdapter(db, { provider: 'pg' }),
  }
})

Client Config — app/auth.client.config.ts

Place this file in the app/ directory so that client auto-imports are available.

The client config is deep-merged with the module's defaults (using defu), so your options take priority while SSR headers and baseURL are filled in automatically.

import { organizationClient } from 'better-auth/client/plugins'

export default defineAuthClientConfig({
  plugins: [organizationClient()],
})

Both files are optional. If absent, the module uses bare defaults.

Module Options

// nuxt.config.ts
export default defineNuxtConfig({
  betterAuthUtils: {
    redirectTo: '/auth/sign-in', // auth middleware redirect
    handlerRoute: '/api/auth/**', // API handler route
  },
})

Usage

Client — useAuth()

Auto-imported composable with reactive session state and raw client access.

const { session, user, loggedIn, ready, signOut, fetch, client } = useAuth()

// Use the raw Better Auth client for any operation
await client.signIn.email({ email, password })
await client.signUp.email({ email, password, name })
await client.organization.create({ name: 'Acme' })

// Convenience helpers
await signOut({ redirectTo: '/login' })
await fetch() // refresh session

Server — useServerAuth()

Auto-imported in server routes.

// server/api/me.ts
export default defineEventHandler(async (event) => {
  const { requireSession } = useServerAuth()
  const session = await requireSession(event) // throws 401 if unauthenticated
  return session.user
})

// Nullable session (no error thrown)
export default defineEventHandler(async (event) => {
  const { getSession } = useServerAuth()
  const session = await getSession(event) // returns null if unauthenticated
  return { loggedIn: !!session }
})

// Advanced: use raw Better Auth instance
export default defineEventHandler(async (event) => {
  const { auth } = useServerAuth()
  const users = await auth.api.listUsers()
})

Protecting Pages

definePageMeta({
  middleware: 'auth',
})

Using the Auth Type

The module exports the server auth instance type via #nuxt-better-auth-utils. This is useful for any client plugin that needs the server type, such as customSessionClient:

Server — server/auth.server.config.ts

import { customSession } from 'better-auth/plugins'

export default defineAuthConfig({
  database: myAdapter(),
  plugins: [
    customSession(async ({ user, session }) => {
      return {
        user,
        session: { ...session, activeOrganization: 'acme' },
      }
    }),
  ],
})

Client — app/auth.client.config.ts

import { customSessionClient } from 'better-auth/client/plugins'
import type { Auth } from '#nuxt-better-auth-utils'

export default defineAuthClientConfig({
  plugins: [customSessionClient<Auth>()],
})

License

MIT