​
Server-Side Setup

​
1. Configure BetterAuth

// apps/server/src/lib/auth.ts
import { betterAuth } from "better-auth";
import { prismaAdapter } from "better-auth/adapters/prisma";

export const auth = betterAuth({
  database: prismaAdapter(prisma, {
    provider: "postgresql",
  }),

  socialProviders: {
    google: {
      clientId: process.env.GOOGLE_CLIENT_ID as string,
      clientSecret: process.env.GOOGLE_CLIENT_SECRET as string,
    },
    // Add more providers here
  },

  trustedOrigins: [
    process.env.CORS_ORIGIN as string,
  ],
});

​
2. Environment Variables in apps/server/.env

# OAuth Providers
GOOGLE_CLIENT_ID=your_google_client_id
GOOGLE_CLIENT_SECRET=your_google_client_secret

# Add more provider credentials as needed

​
Client-Side Implementation

​
1. Auth Client Setup

// apps/web/src/lib/auth-client.ts
import { createAuthClient } from "better-auth/react";

export const authClient = createAuthClient({
  baseURL: process.env.NEXT_PUBLIC_SERVER_URL!,
});

​
2. Social Login Buttons

// apps/web/src/features/auth/social-buttons.tsx
"use client";

import { authClient } from "@/lib/auth-client";
import { Button } from "@/components/ui/button";

export function SocialButtons() {
  const handleGoogleSignIn = async () => {
    try {
     await authClient.signIn.social({
        provider: "google",
        callbackURL: "/dashboard",
        fetchOptions: {
          onError: (ctx) => {
            console.error(ctx.error.message);
          },
        },
      });
    }
  };

  return (
    <div className="space-y-4">
      <Button
        onClick={handleGoogleSignIn}
        className="w-full"
        variant="outline"
      >
        <svg className="mr-2 h-4 w-4" />
        Continue with Google
      </Button>
      {/* Add more provider buttons */}
    </div>
  );
}

​
Authentication Flow

  1. User clicks social provider button
  2. Redirect to provider’s login page
  3. User authenticates with provider
  4. Provider redirects back with code
  5. Exchange code for tokens
  6. Create or update user account
  7. Create session
  8. Redirect to dashboard

​
Security Features

  1. OAuth Security
    • State parameter validation
    • PKCE for mobile apps
    • Secure token storage
    • Token refresh handling
  2. Account Security
    • Email verification
    • Account linking
    • Session management
    • Rate limiting
  3. Data Security
    • Secure user data storage
    • Privacy compliance
    • Data encryption
    • Access control

​
Best Practices

  1. Error Handling
    • Show user-friendly error messages
    • Log authentication errors
    • Handle edge cases
    • Provide fallback options
  2. User Experience
    • Clear provider buttons
    • Loading states
    • Success/error feedback
    • Account linking options
  3. Security
    • HTTPS in production
    • Rate limiting
    • Input validation
    • Token validation

​
Adding New Providers

To add a new social provider:
  1. Register your application with the provider
  2. Get client ID and secret
  3. Add provider configuration to BetterAuth
  4. Create provider button component
  5. Handle provider-specific scopes
  6. Test the integration
Example for adding GitHub: 
// Server-side
export const auth = betterAuth({
  socialProviders: {
    github: {
      clientId: process.env.GITHUB_CLIENT_ID as string,
      clientSecret: process.env.GITHUB_CLIENT_SECRET as string,
    },
  },
});

// Client-side
const handleGithubSignIn = async () => {
  await authClient.signInWithProvider("github");
};

​
Common Issues & Solutions

  1. Callback URL Issues
    • Verify callback URLs in provider dashboard
    • Check CORS configuration
    • Validate redirect URIs
  2. Token Issues
    • Check token expiration
    • Verify token storage
    • Handle token refresh
  3. Account Linking
    • Handle existing accounts
    • Manage multiple providers
    • Resolve conflicts

​
Next Steps