Login with Facebook

To enable Facebook Auth for your project, you need to set up a Facebook OAuth application and add the application credentials to your Supabase Dashboard.

Overview

Setting up Facebook logins for your application consists of 4 parts:

• Create and configure a Facebook Application on the Facebook Developers Site
• Configure email permissions in your Facebook app (required for Supabase Auth)
• Add your Facebook keys to your Supabase Project
• Add the login code to your Supabase JS Client App

Access your Facebook Developer account

• Go to developers.facebook.com.
• Click on Log In at the top right to log in.

Create a Facebook app

• Click on My Apps at the top right.
• Click Create App near the top right.
• Select your app type and click Continue.
• Fill in your app information, then click Create App.
• This should bring you to the screen: Add Products to Your App. (Alternatively you can click on Add Product in the left sidebar to get to this screen.)

<$Partial path="social_provider_setup.mdx" variables={{ "provider": "Facebook" }} />

Set up Facebook login for your Facebook app

From the Add Products to your App screen:

• Click Setup under Facebook Login
• Skip the Quickstart screen. Instead, in the left sidebar, click Settings under Facebook Login
• Enter your callback URI under Valid OAuth Redirect URIs on the Facebook Login Settings page
• Click Save Changes at the bottom right

Your callback URI follows this pattern: https://<project-ref>.supabase.co/auth/v1/callback

You can find your project's callback URI in the Supabase Dashboard under Authentication > Providers > Facebook.

Configure email permissions (required)

This step is required for Supabase Auth to work correctly. Without email permissions, Facebook will not return the user's email address, which may cause authentication failures or incomplete user profiles.

You must configure the email permission in your Facebook app's Use Cases:

1. In your Facebook app dashboard, click Use Cases under Build Your App
2. Find Authentication and Account Creation and click the Edit button on the right
3. Verify that both public_profile and email show status Ready for testing
4. If email is not listed, click the Add button next to it

You can verify the permissions are set correctly by checking that both public_profile and email appear with a green check mark or "Ready for testing" status.

Copy your Facebook app ID and secret

• Click Settings / Basic in the left sidebar
• Copy your App ID from the top of the Basic Settings page
• Under App Secret click Show then copy your secret
• Make sure all required fields are completed on this screen.

Enter your Facebook app ID and secret into your Supabase project

<$Partial path="social_provider_settings_supabase.mdx" variables={{ "provider": "Facebook" }} />

You can also configure the Facebook auth provider using the Management API:

# Get your access token from https://supabase.com/dashboard/account/tokens
export SUPABASE_ACCESS_TOKEN="your-access-token"
export PROJECT_REF="your-project-ref"

# Configure Facebook auth provider
curl -X PATCH "https://api.supabase.com/v1/projects/$PROJECT_REF/config/auth" \
  -H "Authorization: Bearer $SUPABASE_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "external_facebook_enabled": true,
    "external_facebook_client_id": "your-facebook-app-id",
    "external_facebook_secret": "your-facebook-app-secret"
  }'

Add login code to your client app

<Tabs scrollable size="small" type="underlined" defaultActiveId="js" queryGroup="language"

<$Partial path="create_client_snippet.mdx" />

When your user signs in, call signInWithOAuth() with facebook as the provider:

import { createClient } from '@supabase/supabase-js'
const supabase = createClient('https://your-project.supabase.co', 'sb_publishable_... or anon key')

// ---cut---
async function signInWithFacebook() {
  const { data, error } = await supabase.auth.signInWithOAuth({
    provider: 'facebook',
  })

  if (error) {
    console.error('Error signing in with Facebook:', error.message)
    return
  }

  // The user will be redirected to Facebook for authentication
}

When your user signs in, call signInWithOAuth() with facebook as the provider:

Future<void> signInWithFacebook() async {
  await supabase.auth.signInWithOAuth(
    OAuthProvider.facebook,
    redirectTo: kIsWeb ? null : 'my.scheme://my-host', // Optionally set the redirect link to bring back the user via deeplink.
    authScreenLaunchMode:
        kIsWeb ? LaunchMode.platformDefault : LaunchMode.externalApplication, // Launch the auth screen in a new webview on mobile.
  );
}

Alternative: Using Facebook SDK with signInWithIdToken

For more control over the Facebook authentication flow, you can use the Facebook SDK directly and then authenticate with Supabase using signInWithIdToken():

First, add the Facebook SDK dependency to your pubspec.yaml:

dependencies:
  flutter_facebook_auth: ^7.0.0

Check pub.dev for the latest version of flutter_facebook_auth.

Then implement the Facebook authentication:

import 'package:flutter_facebook_auth/flutter_facebook_auth.dart';
import 'package:supabase_flutter/supabase_flutter.dart';

Future<void> signInWithFacebook() async {
  try {
    final LoginResult result = await FacebookAuth.instance.login(
      permissions: ['public_profile', 'email'],
    );

    if (result.status == LoginStatus.success) {
      final accessToken = result.accessToken!.tokenString;

      await Supabase.instance.client.auth.signInWithIdToken(
        provider: OAuthProvider.facebook,
        idToken: accessToken,
      );

      // Authentication successful
    } else {
      // Handle login cancellation or failure
      throw Exception('Facebook login failed: ${result.status}');
    }
  } catch (e) {
    // Handle errors
    throw Exception('Facebook authentication error: ${e.toString()}');
  }
}

Make sure to configure your Facebook app properly and add the required permissions in the Facebook Developer Console. The signInWithIdToken method requires the Facebook access token to be valid and properly scoped.

When your user signs in, call signInWithOAuth() with facebook as the provider:

import SwiftUI

struct SignInWithFacebook: View {
  @Environment(\.webAuthenticationSession) var webAuthenticationSession

  var body: some View {
    Button("Sign in with Facebook") {
      Task {
        do {
          try await supabase.auth.signInWithOAuth(
            provider: .facebook,
            redirectTo: URL(string: "my.scheme://my-host")!,
            launchFlow: { @MainActor url in
              try await webAuthenticationSession.authenticate(
                using: url,
                callbackURLScheme: "my.scheme"
              )
            }
          )
        } catch {
          print("Failed to sign in with Facebook: \(error)")
        }
      }
    }
  }
}

Make sure to configure your app's URL scheme in Xcode under Target > Info > URL Types. The callback URL scheme should match the scheme used in redirectTo (e.g., my.scheme).

When your user signs in, call signInWith(Provider) with Facebook as the Provider:

suspend fun signInWithFacebook() {
	supabase.auth.signInWith(Facebook)
}

<$Partial path="oauth_pkce_flow.mdx" />

<Tabs scrollable size="small" type="underlined" defaultActiveId="js" queryGroup="language"

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

import { createClient } from '@supabase/supabase-js'
const supabase = createClient('https://your-project.supabase.co', 'sb_publishable_... or anon key')

// ---cut---
async function signOut() {
  const { error } = await supabase.auth.signOut()

  if (error) {
    console.error('Error signing out:', error.message)
    return
  }

  // User has been signed out
}

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

Future<void> signOut() async {
  await supabase.auth.signOut();
}

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

func signOut() async throws {
  try await supabase.auth.signOut()
}

When your user signs out, call signOut() to remove them from the browser session and any objects from localStorage:

suspend fun signOut() {
	supabase.auth.signOut()
}

Testing your integration

Facebook apps start in Development mode, which has the following limitations:

• Only users with a role on the app (administrators, developers, testers) can authenticate
• Other users will see an "App Not Setup" error when trying to log in

To add test users:

1. Go to developers.facebook.com and select your app
2. Navigate to App Roles > Roles
3. Add users as Testers, Developers, or Administrators
4. Users must accept the invitation from their Facebook notification settings

Development mode is sufficient for local development and testing. You only need to submit for App Review when you're ready to allow any Facebook user to authenticate with your app.

Going live with app review

Before your app can be used by the general public, you need to complete Facebook's App Review process:

1. Complete App Settings: In your Facebook app's Settings > Basic, fill in all required fields including:

   • App Icon
   • Privacy Policy URL
   • Terms of Service URL (if applicable)
   • App Domain

2. Request Permissions: Navigate to App Review > Permissions and Features and request the permissions you need:

   • public_profile - Usually pre-approved
   • email - Requires verification that your app needs email access

3. Submit for Review: Click Submit for Review and provide:

   • Detailed instructions for how Facebook reviewers should test your login flow
   • A screencast video demonstrating the Facebook Login feature
   • Explanation of how user data will be used

4. Wait for Approval: Facebook typically reviews apps within 1-5 business days

If you only need basic authentication (name and profile picture), you may not need full App Review. Apps requesting only public_profile and email with the "Authenticate and request data from users with Facebook Login" use case can often go live without a detailed review.

For more details, see the Facebook App Review documentation.

Troubleshooting

"App not setup" error

This error occurs when a user without a role on your app tries to log in while the app is in Development mode.

Solution: Either add the user as a tester in your Facebook app settings, or complete the App Review process to make your app available to all users.

User's email not returned

Facebook only returns the email address if:

• The user has a confirmed email on their Facebook account
• Your app has been granted the email permission
• The email permission is marked as "Ready for testing" in Use Cases > Authentication and Account Creation

Solution: Check that the email permission is properly configured in your Facebook app's Use Cases settings.

"Redirect URI mismatch" error

This error indicates the callback URL configured in Facebook doesn't match the one used during authentication.

Solution: Verify that the Valid OAuth Redirect URIs in your Facebook app settings exactly matches https://<project-ref>.supabase.co/auth/v1/callback. Make sure there are no trailing slashes or typos.

Login works in development but not production

If login works locally but fails in production, check:

• Your production URL is added to Valid OAuth Redirect URIs in Facebook
• The App ID and Secret in your Supabase dashboard match your Facebook app
• Your Facebook app is in Live mode (not Development mode)

Resources

• Supabase - Get started for free
• Supabase JS Client
• Facebook Developers Dashboard