Authjs Skills

## Links

- Getting Started: https://authjs.dev/getting-started/installation?framework=Next.js
- Migrating to v5: https://authjs.dev/getting-started/migrating-to-v5
- Google Provider: https://authjs.dev/getting-started/providers/google
- Credentials Provider: https://authjs.dev/getting-started/providers/credentials
- Core API Reference: https://authjs.dev/reference/core
- Session Management: https://authjs.dev/getting-started/session-management
- Concepts: https://authjs.dev/concepts

## Installation

```sh
pnpm add next-auth@beta
```

**Note**: Auth.js v5 is currently in beta. Use `next-auth@beta` to install the latest v5 version.

## What's New in Auth.js v5?

### Key Changes from v4

- **Simplified Configuration**: More streamlined setup with better TypeScript support
- **Universal `auth()` Export**: Single function for authentication across all contexts
- **Enhanced Security**: Improved CSRF protection and session handling
- **Edge Runtime Support**: Full compatibility with Edge Runtime and middleware
- **Better Type Safety**: Improved TypeScript definitions throughout

## Environment Variables

### Required Environment Variables

```env
# Auth.js Configuration
AUTH_SECRET=your_secret_key_here

# Google OAuth (if using Google provider)
AUTH_GOOGLE_ID=your_google_client_id
AUTH_GOOGLE_SECRET=your_google_client_secret

# For production deployments
AUTH_URL=https://yourdomain.com

# For development (optional, defaults to http://localhost:3000)
# AUTH_URL=http://localhost:3000
```

### Generating AUTH_SECRET

```sh
# Generate a random secret (Unix/Linux/macOS)
openssl rand -base64 32

# Alternative using Node.js
node -e "console.log(require('crypto').randomBytes(32).toString('base64'))"

# Using pnpm
pnpm dlx auth secret
```

**Important**: Never commit `AUTH_SECRET` to version control. Use `.env.local` for development.

## Basic Setup (Next.js App Router)

### 1. Create `auth.ts` Configuration File

Create `auth.ts` at the project root (next to `package.json`):

```typescript
import NextAuth from "next-auth"
import Google from "next-auth/providers/google"
import Credentials from "next-auth/providers/credentials"

export const { handlers, signIn, signOut, auth } = NextAuth({
  providers: [
    Google({
      clientId: process.env.AUTH_GOOGLE_ID,
      clientSecret: process.env.AUTH_GOOGLE_SECRET,
    }),
    Credentials({
      credentials: {
        email: { label: "Email", type: "email" },
        password: { label: "Password", type: "password" },
      },
      authorize: async (credentials) => {
        // TODO: Implement your authentication logic here
        // This is a basic example - see Credentials Provider section below for complete implementation
        if (!credentials?.email || !credentials?.password) {
          return null
        }

        // Example: validate against database (placeholder)
        // See "Credentials Provider" section for full implementation with bcrypt
        const user = { id: "1", email: credentials.email, name: "User" } // Replace with actual DB lookup
        
        if (!user) {
          return null
        }

        return {
          id: user.id,
          email: user.email,
          name: user.name,
        }
      },
    }),
  ],
  pages: {
    signIn: '/auth/signin',
  },
  callbacks: {
    authorized: async ({ auth }) => {
      // Return true if user is authenticated
      return !!auth
    },
  },
})
```

**Note**: This is a basic setup example. For production-ready credentials authentication, see the "Credentials Provider" section below which includes proper password hashing with bcrypt and database integration.

### 2. Create API Route Handler

Create `app/api/auth/[...nextauth]/route.ts`:

```typescript
import { handlers } from "@/auth"

export const { GET, POST } = handlers
```

### 3. A