Next.js Supabase Auth Template

Production-ready authentication system for Next.js 15 + Supabase projects.

Features

✅ Security Hardened

• PKCE Flow for OAuth
• RLS policies with least-privilege
• SQL Injection protection (search_path)
• Token validation with error handling

✅ Complete Auth Flow

• Email/Password signup & login
• Google OAuth
• Email confirmation
• Password reset
• Auto profile creation

✅ Template Ready

• Centralized config (auth.config.ts)
• Environment validation
• Type-safe configuration
• Reusable across projects

✅ UI Components (shadcn/ui)

• LoginForm
• SignupForm
• ForgotPasswordForm
• ResetPasswordForm
• GoogleLoginButton

Profile Schema

Assumes public.profiles table with:

• user_id (uuid, FK to auth.users)
• email (text)
• first_name (text)
• last_name (text)
• mobile (text, nullable)
• role (text, default: 'user')

Usage

/nextjs-supabase-auth

This will:

1. Copy all auth files to your project
2. Create configuration files
3. Generate database migrations
4. Provide setup instructions

What You Need to Configure

After installation:

1. Environment Variables (.env.local):

   NEXT_PUBLIC_SUPABASE_URL=your-project-url
   NEXT_PUBLIC_SUPABASE_ANON_KEY=your-anon-key
   NEXT_PUBLIC_SITE_URL=http://localhost:3000
   

2. Auth Config (lib/auth.config.ts):

   redirects: {
     afterLogin: '/dashboard',  // ← Change to your dashboard path
     // ...
   }
   

3. Apply Migrations:

   • Run migrations in supabase/migrations/
   • Or use Supabase Dashboard

4. Enable OAuth (optional):

   • Configure Google OAuth in Supabase Dashboard
   • Add callback URL: {SITE_URL}/auth/callback

Files Installed

app/
├── actions/auth.ts              # Server actions
└── auth/
    ├── callback/route.ts        # OAuth & email callback
    ├── login/page.tsx
    ├── signup/page.tsx
    ├── forgot-password/page.tsx
    ├── reset-password/page.tsx
    └── verify-email/page.tsx

components/auth/
├── LoginForm.tsx
├── SignupForm.tsx
├── ForgotPasswordForm.tsx
├── ResetPasswordForm.tsx
└── GoogleLoginButton.tsx

lib/
├── auth.config.ts               # Auth configuration
├── env.ts                       # Environment validation
└── supabase/
    ├── client.ts                # Browser client
    ├── server.ts                # Server client
    └── middleware.ts            # Route protection

middleware.ts                    # Next.js middleware

supabase/migrations/
└── fix_function_search_path.sql # Security patch

Dependencies Required

npm install @supabase/supabase-js @supabase/ssr
npm install lucide-react          # Icons

shadcn/ui components needed:

• button
• input
• label
• card

Security Notes

✅ PKCE flow enabled for OAuth ✅ RLS policies protect user data ✅ SQL injection protection on all functions ✅ Token validation with error handling ✅ Environment variables validated on startup

Customization

Change redirect paths: Edit lib/auth.config.ts Change profile fields: Edit app/actions/auth.ts signup function Change UI text: Edit component files in components/auth/ Add i18n: Extend auth.config.ts with text config

Support

Issues? Check:

1. Environment variables are set correctly
2. Supabase project is configured
3. Migrations are applied
4. OAuth providers are enabled (if using)

Version

Created: 2025-01-11 Compatible with:

• Next.js 15+
• React 19+
• Supabase (latest)
• shadcn/ui