Supabase Authentication with React: A Complete Guide

Hey guys! Today, we’re diving deep into the world of Supabase and React to explore how to implement authentication in your web applications. Supabase is an open-source Firebase alternative that provides all the backend features you need to build scalable and secure apps, and React, as we all know, is one of the most popular JavaScript libraries for building user interfaces. Combining these two technologies makes for a powerful and efficient development experience. So, buckle up, because we’re about to embark on a journey to create a robust authentication system using Supabase and React!

Why Supabase and React?

Let’s kick things off by understanding why choosing Supabase with React is a smart move. First off, Supabase simplifies backend development. It offers a suite of tools like a Postgres database, authentication, real-time subscriptions, and storage, all wrapped in an easy-to-use interface. Instead of spending countless hours setting up and managing these services yourself, Supabase handles the heavy lifting, allowing you to focus on building the frontend of your application with React. React, on the other hand, provides a component-based architecture that promotes code reusability and maintainability. Its virtual DOM makes updates efficient, resulting in a smooth user experience. When you pair React with Supabase, you get a full-stack solution that accelerates development and reduces complexity. Supabase’s authentication service supports various methods, including email/password, OAuth providers (like Google, GitHub, and more), and magic links. This flexibility allows you to cater to different user preferences and ensure a seamless login experience. Moreover, Supabase provides client libraries that simplify interactions with its services from your React application. These libraries handle tasks like signing up users, signing in, managing sessions, and securely storing user data. With these tools at your disposal, you can quickly implement authentication without having to write complex backend code. Supabase also integrates well with React’s ecosystem, allowing you to leverage popular libraries and tools like React Router, Redux, and Zustand to manage application state and navigation. This integration enhances the development workflow and enables you to build sophisticated features with ease.

Setting Up Your Supabase Project

Before we start coding, let’s set up our Supabase project. First, head over to the Supabase website ( https://supabase.com/ ) and create a new account or log in if you already have one. Once you’re in, create a new project. You’ll need to choose a name, a database password, and a region. Make sure to keep these details handy, as you’ll need them later to connect your React application to your Supabase backend. After creating your project, navigate to the “Authentication” section in the Supabase dashboard. Here, you can configure various authentication settings, such as enabling specific sign-in methods (e.g., email/password, Google, GitHub), setting up email templates, and defining user roles and permissions. Take some time to explore these settings and configure them according to your application’s requirements. Next, you’ll need to enable the authentication providers you want to support in your application. For example, if you want to allow users to sign in with their Google accounts, you’ll need to configure the Google OAuth provider in the Supabase dashboard. This involves creating a new OAuth client in the Google Cloud Console and providing the client ID and secret to Supabase. Similarly, you can configure other OAuth providers like GitHub, Facebook, and Twitter. Once you’ve configured your authentication settings and enabled the desired providers, you’re ready to start building your React application. Make sure to note down your Supabase URL and API key from the project settings, as you’ll need these to initialize the Supabase client in your React application. With your Supabase project set up and configured, you’re well on your way to implementing authentication in your React application. In the next sections, we’ll walk you through the process of creating a new React project, installing the Supabase client library, and implementing sign-up, sign-in, and sign-out functionality.

Creating a New React App

Alright, let’s get our hands dirty and create a new React application. Open up your terminal and run the following command:

npx create-react-app supabase-auth-app
cd supabase-auth-app

This will create a new React project named supabase-auth-app using Create React App. Once the project is created, navigate into the project directory using the cd command. Next, we need to install the Supabase client library. Run the following command:

npm install @supabase/supabase-js

This command will install the @supabase/supabase-js package, which provides the necessary functions to interact with your Supabase backend from your React application. After installing the Supabase client library, you need to initialize it with your Supabase URL and API key. Create a new file named supabaseClient.js in the src directory of your React project. Open this file and add the following code:

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

const supabaseUrl = process.env.REACT_APP_SUPABASE_URL;
const supabaseKey = process.env.REACT_APP_SUPABASE_ANON_KEY;
const supabase = createClient(supabaseUrl, supabaseKey);

export default supabase;

Make sure to replace process.env.REACT_APP_SUPABASE_URL and process.env.REACT_APP_SUPABASE_ANON_KEY with your actual Supabase URL and API key, respectively. You can find these values in the project settings of your Supabase dashboard. It’s recommended to store these values as environment variables to keep them secure and prevent them from being exposed in your codebase. To do this, create a .env file in the root directory of your React project and add the following lines:

REACT_APP_SUPABASE_URL=your_supabase_url
REACT_APP_SUPABASE_ANON_KEY=your_supabase_anon_key

Replace your_supabase_url and your_supabase_anon_key with your actual Supabase URL and API key. Remember to restart your development server after creating or modifying the .env file for the changes to take effect. With the Supabase client initialized, you’re now ready to start implementing authentication functionality in your React application. In the next sections, we’ll cover how to create sign-up, sign-in, and sign-out components using the Supabase client library.

Implementing Sign-Up

Now, let’s implement the sign-up functionality. Create a new component called SignUp.js in the src/components directory. This component will handle the user registration process. Here’s the basic structure:

import React, { useState } from 'react';
import supabase from '../supabaseClient';

const SignUp = () => {
 const [email, setEmail] = useState('');
 const [password, setPassword] = useState('');

 const handleSubmit = async (e) => {
 e.preventDefault();

 const { user, error } = await supabase.auth.signUp({
 email: email,
 password: password,
 });

 if (error) {
 console.error('Error signing up:', error.message);
 } else {
 console.log('User signed up successfully:', user);
 }
 };

 return (
 <form onSubmit={handleSubmit}>
 <label>
 Email:
 <input
 type="email"
 value={email}
 onChange={(e) => setEmail(e.target.value)}
 />
 </label>
 <label>
 Password:
 <input
 type="password"
 value={password}
 onChange={(e) => setPassword(e.target.value)}
 />
 </label>
 <button type="submit">Sign Up</button>
 </form>
 );
};

export default SignUp;

In this component, we’re using the useState hook to manage the email and password input fields. The handleSubmit function is called when the form is submitted. Inside this function, we call supabase.auth.signUp with the email and password provided by the user. This function sends a request to the Supabase backend to create a new user account. If the sign-up process is successful, the user object will contain the user’s data. If there’s an error, the error object will contain the error message. We then log the user data or error message to the console. Remember to handle errors appropriately in your application, such as displaying an error message to the user. You can also redirect the user to a different page after successful sign-up. To use this component in your application, import it into your App.js file and render it:

import React from 'react';
import SignUp from './components/SignUp';

const App = () => {
 return (
 <div>
 <h1>Supabase Auth with React</h1>
 <SignUp />
 </div>
 );
};

export default App;

Now, when you run your React application, you should see the sign-up form. Users can enter their email and password and click the “Sign Up” button to create a new account. You can verify that the user account has been created by checking the “Authentication” section in your Supabase dashboard. With the sign-up functionality implemented, you’re one step closer to building a complete authentication system with Supabase and React. In the next section, we’ll cover how to implement the sign-in functionality.

Implementing Sign-In

Next up, let’s implement the sign-in functionality. Create a new component called SignIn.js in the src/components directory. This component will handle the user login process. Here’s the basic structure:

import React, { useState } from 'react';
import supabase from '../supabaseClient';

const SignIn = () => {
 const [email, setEmail] = useState('');
 const [password, setPassword] = useState('');

 const handleSubmit = async (e) => {
 e.preventDefault();

 const { user, session, error } = await supabase.auth.signInWithPassword({
 email: email,
 password: password,
 });

 if (error) {
 console.error('Error signing in:', error.message);
 } else {
 console.log('User signed in successfully:', user);
 console.log('Session:', session);
 }
 };

 return (
 <form onSubmit={handleSubmit}>
 <label>
 Email:
 <input
 type="email"
 value={email}
 onChange={(e) => setEmail(e.target.value)}
 />
 </label>
 <label>
 Password:
 <input
 type="password"
 value={password}
 onChange={(e) => setPassword(e.target.value)}
 />
 </label>
 <button type="submit">Sign In</button>
 </form>
 );
};

export default SignIn;

In this component, we’re using the useState hook to manage the email and password input fields, just like in the SignUp component. The handleSubmit function is called when the form is submitted. Inside this function, we call supabase.auth.signInWithPassword with the email and password provided by the user. This function sends a request to the Supabase backend to authenticate the user. If the sign-in process is successful, the user object will contain the user’s data, and the session object will contain the user’s session information. If there’s an error, the error object will contain the error message. We then log the user data, session information, or error message to the console. Remember to handle errors appropriately in your application, such as displaying an error message to the user. You can also redirect the user to a different page after successful sign-in. To use this component in your application, import it into your App.js file and render it:

import React from 'react';
import SignUp from './components/SignUp';
import SignIn from './components/SignIn';

const App = () => {
 return (
 <div>
 <h1>Supabase Auth with React</h1>
 <SignUp />
 <SignIn />
 </div>
 );
};

export default App;

Now, when you run your React application, you should see both the sign-up and sign-in forms. Users can enter their email and password and click the “Sign In” button to log in to their account. You can verify that the user has been signed in successfully by checking the console for the user data and session information. With the sign-in functionality implemented, you’re one step closer to building a complete authentication system with Supabase and React. In the next section, we’ll cover how to implement the sign-out functionality.

Implementing Sign-Out

Finally, let’s implement the sign-out functionality. This will allow users to securely log out of your application. Create a new component called SignOut.js in the src/components directory. Here’s the basic structure:

import React from 'react';
import supabase from '../supabaseClient';

const SignOut = () => {
 const handleSignOut = async () => {
 const { error } = await supabase.auth.signOut();

 if (error) {
 console.error('Error signing out:', error.message);
 } else {
 console.log('User signed out successfully');
 }
 };

 return (
 <button onClick={handleSignOut}>Sign Out</button>
 );
};

export default SignOut;

In this component, we define a handleSignOut function that calls supabase.auth.signOut . This function sends a request to the Supabase backend to invalidate the user’s session. If the sign-out process is successful, the error object will be null. If there’s an error, the error object will contain the error message. We then log the success or error message to the console. Remember to handle errors appropriately in your application, such as displaying an error message to the user. You can also redirect the user to a different page after successful sign-out. To use this component in your application, import it into your App.js file and render it:

import React from 'react';
import SignUp from './components/SignUp';
import SignIn from './components/SignIn';
import SignOut from './components/SignOut';

const App = () => {
 return (
 <div>
 <h1>Supabase Auth with React</h1>
 <SignUp />
 <SignIn />
 <SignOut />
 </div>
 );
};

export default App;

Now, when you run your React application, you should see the sign-out button. When a user clicks this button, they will be logged out of your application. You can verify that the user has been signed out successfully by checking the console for the success message. With the sign-out functionality implemented, you have now built a complete authentication system with Supabase and React. This system allows users to sign up, sign in, and sign out of your application securely. Remember to handle errors appropriately and provide a seamless user experience.

Conclusion

So there you have it! We’ve successfully implemented a full authentication flow using Supabase and React . Supabase makes the backend stuff a breeze, and React helps us build a slick user interface. By following the steps outlined in this guide, you can quickly add authentication to your React applications and focus on building amazing features. Remember to explore the Supabase documentation for more advanced features and customization options. Happy coding, and see you in the next guide!