auth

Gets the session and forwards authentication cookies to the response.

Import

import { auth } from 'start-authjs'

Signature

function auth(
  context: AuthRequestContext,
  config: StartAuthJSConfig
): Promise<AuthSession | null>

Parameters

context

An object containing:

• request: The incoming Request object
• response: The Response object to forward cookies to

config

Your auth configuration object.

Returns

Returns Promise<AuthSession | null>:

• AuthSession object if the user is authenticated (with user and expires properties)
• null if no valid session exists

Usage

import { auth } from 'start-authjs'
import { authConfig } from '~/utils/auth'

const session = await auth(
  {
    request,
    response: new Response(),
  },
  authConfig
)

if (session) {
  console.log('User:', session.user.name)
}

When to Use

Use auth() instead of getSession() when:

• You need to refresh session cookies
• You're implementing middleware that modifies the response
• The session token needs to be extended

Notes

• Automatically sets trustHost: true if not specified
• Parses and forwards Set-Cookie headers from Auth.js response
• Uses set-cookie-parser internally for proper cookie handling