Supabase Auth: Custom Display Names On Signup

Hey guys! Ever wondered how to let users choose their display names during signup with Supabase Auth? It's a pretty common requirement, right? You want your users to have a personalized experience from the get-go. Well, buckle up, because we're diving deep into Supabase Auth signup and how to customize it to include display names. We'll walk through the process step-by-step, making sure you understand everything from the database setup to the frontend implementation. This guide is designed for both beginners and those with some experience with Supabase. So, whether you're new to the game or looking to refine your skills, you're in the right place. We'll break down the code, explain the logic, and ensure you can get this feature up and running in your project. Let's get started!

Setting up Your Supabase Project

Alright, before we get our hands dirty with code, let's set the stage. First things first: you'll need a Supabase project. If you don't already have one, head over to Supabase and create a new project. It's super easy, and they have a great free tier to get you started. Once your project is created, navigate to the SQL editor. Here's where we'll set up our database to store the display names. We need to modify the auth.users table or create a new one to store this extra information. I recommend creating a new table to keep things clean. You can do this by using the Supabase SQL editor or the Supabase dashboard. It's generally better to create a new table because modifying the auth.users table directly can sometimes lead to issues down the line. We want to be able to easily add and remove this functionality.

Let's get into the SQL code. In your SQL editor, create a table named profiles. This table will hold user profiles, including their display names. The profiles table should contain the following columns: id (UUID, primary key, and should reference the auth.users table), display_name (text, to store the display name), and any other relevant profile information. It should also have a foreign key that references the auth.users table. This creates a relationship between your profiles and your user accounts. This structure ensures that each user has a unique profile. With this setup, you have a solid foundation to store and manage user display names alongside their authentication data. Creating a separate profiles table lets you to manage user display names with flexibility and without altering the core structure of your Supabase authentication. We also need to add a trigger. Triggers allow us to execute a function automatically in response to certain events on a table. In our case, we'll use a trigger to automatically create a profile for a new user when they sign up. This means, every time a new user registers through Supabase Auth, a corresponding record is automatically created in your profiles table, ensuring that each user has a profile ready to go.

CREATE TABLE profiles (
  id UUID PRIMARY KEY REFERENCES auth.users(id),
  display_name TEXT,
  created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
  updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);

CREATE OR REPLACE FUNCTION public.handle_new_user()
RETURNS TRIGGER
AS $
BEGIN
  INSERT INTO public.profiles (id, display_name) -- Add any other default profile info here
  VALUES (NEW.id, NEW.raw_user_meta_data->>'display_name');
  RETURN NEW;
END;
$ LANGUAGE plpgsql;

CREATE TRIGGER on_auth_user_created
  AFTER INSERT ON auth.users
  FOR EACH ROW
  EXECUTE PROCEDURE public.handle_new_user();

ALTER TABLE auth.users
  ENABLE ROW LEVEL SECURITY;

CREATE POLICY "Users can view their own profile" ON public.profiles
  FOR SELECT
  TO authenticated
  USING (auth.uid() = id);

CREATE POLICY "Users can update their own profile" ON public.profiles
  FOR UPDATE
  TO authenticated
  USING (auth.uid() = id);

Once you've run the SQL, your database is ready to handle display names. Now, let’s get into the frontend.

Frontend Implementation: The Signup Form

Now for the fun part: building the signup form! We'll use JavaScript (you can use your preferred framework like React, Vue, or Angular) and the Supabase JavaScript client library. First, make sure you have the Supabase client library installed in your project. You can install it via npm or yarn. In your signup form, we will modify the default signup to accept the display name. This includes an input field for the user to enter their desired display name. Then, we need to modify our signup logic to include this data. We'll use Supabase's auth.signUp() method, but we'll include the display_name in the user_metadata. This is how you pass additional user data to Supabase. This data will be available to you on the server side when the user is created. Remember that all user data is stored as a JSON object, so you will need to retrieve it as such. This step is crucial for the correct flow of data from the frontend to the backend, enabling the custom display name feature. If you use a framework like React, you'll manage the form state using the useState hook. This ensures that the form values are updated dynamically.

Let’s get into some example code. Here's a basic example using JavaScript. This example gives you a basic foundation to build upon and integrate with your user interface. Make sure you adjust the code according to your project's specific requirements. Remember to handle potential errors, such as invalid input or network issues, to provide a smooth user experience. This includes providing informative error messages and appropriate feedback to the user when something goes wrong.

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

const supabaseUrl = 'YOUR_SUPABASE_URL'
const supabaseAnonKey = 'YOUR_SUPABASE_ANON_KEY'

const supabase = createClient(supabaseUrl, supabaseAnonKey)

async function signUpWithDisplayName(email, password, displayName) {
  const { data, error } = await supabase.auth.signUp({
    email,
    password,
    options: {
      data: {
        display_name: displayName,
      },
    },
  })

  if (error) {
    console.error('Signup error:', error)
    return error
  } else {
    console.log('Signup successful:', data)
    return data
  }
}

// Example usage
const email = 'user@example.com'
const password = 'password123'
const displayName = 'John Doe'

signUpWithDisplayName(email, password, displayName)
  .then(data => {
    if (data && data.user) {
      alert('Signup successful! Check your email to confirm.')
    }
  })
  .catch(error => {
    alert('Signup failed. See console for details.')
  })

In this code, we call supabase.auth.signUp() and pass the display_name in the options.data. The display name will be stored in the raw_user_meta_data field within the auth.users table. Now, when a user signs up, the display name they entered is sent to Supabase. Now you have a working signup form with display names.

Displaying the Display Name

Once a user has signed up, you'll want to display their display name somewhere in your app (e.g., in a profile section, dashboard, etc.). Retrieving the display name is straightforward. You have a few options for where and how you retrieve the display name. One option is to fetch the user's profile information directly from the profiles table after they log in. Another is to fetch the information in your app, when the user first logs in. Then you can update the information in your app to store the user's information. You'll query the profiles table using the user's id. You will use supabase.auth.getUser() to get the user's id. Then, use supabase.from('profiles').select('*').eq('id', userId) to fetch the user's profile. Remember to use row-level security (RLS) policies on your profiles table to ensure that users can only access their own profile information.

Here’s how you can get and display the display name in your app. This assumes you have implemented user authentication and have access to the user's session data. Keep in mind that error handling is crucial in any real-world application. Provide informative error messages and handle edge cases gracefully to ensure a smooth user experience. This includes providing feedback to users when things go wrong and handling potential issues with data retrieval or display.

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

const supabaseUrl = 'YOUR_SUPABASE_URL'
const supabaseAnonKey = 'YOUR_SUPABASE_ANON_KEY'

const supabase = createClient(supabaseUrl, supabaseAnonKey)

async function getUserDisplayName() {
  const { data: { user }, error: authError } = await supabase.auth.getUser()

  if (authError) {
    console.error('Authentication error:', authError)
    return null
  }

  if (!user) {
    console.log('No user logged in.')
    return null
  }

  const { data: profile, error: profileError } = await supabase
    .from('profiles')
    .select('display_name')
    .eq('id', user.id)
    .single()

  if (profileError) {
    console.error('Profile fetch error:', profileError)
    return null
  }

  return profile?.display_name || null
}

// Example usage
getUserDisplayName()
  .then(displayName => {
    if (displayName) {
      console.log('Display Name:', displayName)
    }
  })

This code retrieves the user's display name from the profiles table and displays it in the console. Remember to replace 'YOUR_SUPABASE_URL' and 'YOUR_SUPABASE_ANON_KEY' with your actual Supabase project credentials. By now, you should be able to display the user's display name.

Advanced Tips and Considerations

Let’s dive into some advanced tips and best practices to enhance your implementation. Consider adding validation to your frontend form to ensure the display name meets your requirements (e.g., length restrictions, acceptable characters). You can use regular expressions or custom validation functions. Error handling is also super important. Display informative error messages to your users when something goes wrong. Handle network errors and provide appropriate feedback. Implement data sanitization on the backend to prevent malicious input. This might involve cleaning the display name to remove any potentially harmful code. You may want to consider using a user-friendly way to notify the user that their account has been created. Use Supabase functions to perform more complex operations or custom logic on the backend. You can use these functions for things like sending welcome emails or validating user input. Always follow security best practices. Secure your Supabase project by configuring RLS correctly and by keeping your API keys safe. These practices are essential for building secure and reliable applications. Remember to use best practices like input validation, data sanitization, and security measures to maintain the integrity of your application. These steps will help you provide a better experience.

Conclusion

And that's it! You've successfully added the ability for users to set their display names during signup in your Supabase Auth setup. We've covered everything from setting up your database, to creating the signup form, and displaying the display name in your app. This is just one way to customize your Supabase Auth flow. Supabase gives you a lot of flexibility. Remember, this is a starting point, so feel free to experiment and tailor it to your needs. This feature not only enhances user experience but also makes your application more personalized and engaging. Now, go forth and build amazing things! Happy coding!