Google Login With Supabase In Next.js: A Quick Guide

by Alex Braham 53 views

Hey guys! In this article, we're going to dive into how to set up Google login with Supabase in your Next.js application. Supabase is an awesome open-source alternative to Firebase, and Next.js is a fantastic React framework for building fast, modern web applications. Combining these two gives you a powerful stack for creating amazing projects. So, let's get started!

Setting Up Supabase

First things first, you'll need a Supabase account. Head over to Supabase and sign up. Once you're in, create a new project. Give it a name and choose a region that's closest to your users. After your project is set up, you'll find yourself in the Supabase dashboard. This is where the magic happens!

Configure Google Authentication

Now, let’s enable Google authentication. In your Supabase dashboard, navigate to Authentication > Providers, and find Google. Enable it, and you’ll need to configure the OAuth credentials. To do this, you’ll need to create a new OAuth client in the Google Cloud Console.

  1. Go to the Google Cloud Console.
  2. Create a new project or select an existing one.
  3. In the navigation menu, go to APIs & Services > Credentials.
  4. Click Create Credentials and select OAuth client ID.
  5. Configure your OAuth client ID:
    • Application type: Web application
    • Name: Give it a descriptive name (e.g., "Supabase Next.js Google Login")
    • Authorized JavaScript origins: This should be your Next.js development URL (e.g., http://localhost:3000) and your production URL (e.g., https://your-app.com).
    • Authorized redirect URIs: This is crucial! It should be your Supabase project’s callback URL. You can find this in the Supabase Google Auth settings. It usually looks like https://your-supabase-project-id.supabase.co/auth/v1/callback.
  6. Click Create. You’ll get a Client ID and a Client Secret. Copy these down – you’ll need them for the next step.

Back in your Supabase dashboard, paste the Client ID and Client Secret into the Google authentication settings. Save the configuration. Congrats, you've just configured Google authentication with Supabase!

Setting Up Your Next.js Application

Alright, now let's move on to the Next.js side of things. If you don't already have a Next.js project, create one using:

npx create-next-app my-app
cd my-app

Install Supabase Client

Next, install the Supabase client library:

npm install @supabase/supabase-js

Initialize Supabase Client

Create a supabaseClient.js file (or .ts if you're using TypeScript) to initialize the Supabase client. This file will handle the connection to your Supabase project.

// supabaseClient.js
import { createClient } from '@supabase/supabase-js';

const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL;
const supabaseKey = process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY;

export const supabase = createClient(supabaseUrl, supabaseKey);

Make sure you have your Supabase URL and anon key in your .env.local file:

NEXT_PUBLIC_SUPABASE_URL=your_supabase_url
NEXT_PUBLIC_SUPABASE_ANON_KEY=your_supabase_anon_key

Important: The NEXT_PUBLIC_ prefix makes these variables accessible in your browser code.

Implementing Google Login

Now for the fun part – implementing the Google login! Create a component (e.g., LoginButton.js) that will handle the authentication flow.

// LoginButton.js
import { supabase } from './supabaseClient';

const LoginButton = () => {
  const handleLogin = async () => {
    const { data, error } = await supabase.auth.signInWithOAuth({
      provider: 'google',
      options: {
        redirectTo: 'http://localhost:3000/profile', // Replace with your actual redirect URL
      },
    });

    if (error) {
      console.error('Google login error:', error);
    }
  };

  return (
    <button onClick={handleLogin}>
      Sign in with Google
    </button>
  );
};

export default LoginButton;

In this component:

  • We import the supabase client we initialized earlier.
  • The handleLogin function calls supabase.auth.signInWithOAuth with the google provider.
  • The redirectTo option specifies where the user should be redirected after successful authentication. Make sure this URL matches the one you configured in your Google OAuth client and Supabase settings.

Displaying the Login Button

Now, let's display the login button in your pages/index.js file:

// pages/index.js
import LoginButton from '../components/LoginButton';

const Home = () => {
  return (
    <div>
      <h1>Welcome to My App</h1>
      <LoginButton />
    </div>
  );
};

export default Home;

Handling the Redirect

After the user successfully authenticates with Google, they’ll be redirected back to your application. You'll need to handle this redirect and update your application state accordingly. Create a pages/profile.js page (or whatever you set as your redirectTo URL):

// pages/profile.js
import { useState, useEffect } from 'react';
import { supabase } from '../supabaseClient';

const Profile = () => {
  const [user, setUser] = useState(null);

  useEffect(() => {
    async function fetchUser() {
      const { data: { user } } = await supabase.auth.getUser();
      setUser(user);
    }

    fetchUser();
  }, []);

  if (!user) {
    return <p>Loading...</p>;
  }

  return (
    <div>
      <h1>Welcome, {user.email}!</h1>
      <p>User ID: {user.id}</p>
      <button onClick={async () => {
        await supabase.auth.signOut();
        window.location.href = '/'; // Redirect to home page after sign out
      }}>
        Sign Out
      </button>
    </div>
  );
};

export default Profile;

In this component:

  • We use useEffect to fetch the current user from Supabase.
  • We display the user's email and ID.
  • We add a sign-out button that calls supabase.auth.signOut and redirects the user to the home page.

Securing Your Application

Security is paramount. Always ensure that your Supabase URL and anon key are stored securely. Never commit them directly to your codebase. Use environment variables and .env.local files (which should be added to your .gitignore).

Also, be mindful of the redirect URLs. Make sure they are properly configured in both your Google Cloud Console and Supabase settings to prevent potential security vulnerabilities.

Conclusion

And there you have it! You've successfully implemented Google login with Supabase in your Next.js application. This setup provides a secure and straightforward way for users to authenticate, leveraging the power of Supabase and the flexibility of Next.js.

Remember to handle errors gracefully, provide clear feedback to your users, and always prioritize security. Happy coding, and feel free to reach out if you have any questions or run into any issues! Good luck with your projects!

SEO Optimization Tips

To ensure your guide ranks well in search engines, consider the following tips:

  1. Keyword Integration: Naturally incorporate keywords like "Supabase login," "Next.js authentication," and "Google OAuth" throughout the content. But remember to write naturally.
  2. Header Optimization: Use headers (H2, H3, etc.) to structure your content logically, making it easier for both users and search engines to understand. Each section should address a specific aspect of the topic.
  3. Internal and External Linking: Link to relevant resources within your site (internal links) and to authoritative sources outside your site (external links). This enhances the credibility and value of your content.
  4. Image Optimization: Use descriptive alt text for images to improve accessibility and SEO. Compress images to reduce file size and improve page load speed.
  5. Mobile-Friendliness: Ensure your guide is responsive and provides a seamless experience on all devices, as mobile-friendliness is a ranking factor.

By implementing these strategies, you can improve your guide’s visibility and attract more readers interested in setting up Google login with Supabase in Next.js.

Troubleshooting Common Issues

Even with careful setup, you might encounter some common issues. Here’s how to troubleshoot them:

  • Redirect URI Mismatch: Ensure the redirect URIs in your Google Cloud Console, Supabase settings, and Next.js code match exactly. This is the most common cause of authentication failures.
  • CORS Errors: If you see CORS errors, double-check that your Supabase URL is correctly configured in your Next.js application and that your Supabase project allows requests from your application’s domain.
  • Environment Variable Issues: Verify that your environment variables (Supabase URL and anon key) are correctly set in your .env.local file and are accessible in your Next.js code. Restart your development server after making changes to environment variables.
  • Supabase Client Initialization: Ensure that your Supabase client is initialized correctly with the correct URL and key. Test the initialization by making a simple request to your Supabase project.
  • Google OAuth Configuration: Double-check your Google OAuth configuration in the Google Cloud Console. Ensure that the application type is set to "Web application" and that the Authorized JavaScript origins and Authorized redirect URIs are correctly configured.

By systematically checking these common issues, you can quickly identify and resolve problems, ensuring a smooth authentication experience for your users.

Advanced Configuration Options

Once you have the basic setup working, you might want to explore advanced configuration options to customize the authentication flow and enhance the user experience. Here are some ideas:

  • Custom Claims: Add custom claims to the user’s JWT (JSON Web Token) to include additional information about the user. This can be useful for implementing role-based access control or storing user-specific data.
  • Social Provider Linking: Allow users to link multiple social providers to a single account. This gives users more flexibility and control over their authentication options.
  • Multi-Factor Authentication (MFA): Implement MFA to add an extra layer of security to your application. Supabase supports MFA through various methods, such as SMS codes or authenticator apps.
  • Custom UI: Customize the look and feel of the authentication UI to match your application’s branding. Supabase provides options for customizing the authentication flow and UI elements.
  • Server-Side Rendering (SSR): Implement server-side rendering for your authentication pages to improve performance and SEO. This can be particularly useful for pages that require authentication before rendering.

By exploring these advanced configuration options, you can create a more robust and user-friendly authentication system that meets the specific needs of your application.

Remember to stay awesome and keep building amazing things!