How to design the video sharing web app with nextjs

To set up a system where users can access video course files stored on AWS S3 after purchasing a course on your site built with Next.js, follow these detailed steps. This process involves backend setup for handling purchases and access rights, and S3 configuration for secure file storage and access.

Step 1: Set Up AWS S3

1. Create an S3 Bucket:

   • Log in to your AWS Management Console.
   • Navigate to S3 and create a new bucket.
   • Apply the necessary permissions to ensure that the bucket is not publicly accessible. You can manage access through bucket policies or IAM roles.

2. Upload Video Files:

   • Upload your course video files to the S3 bucket.
   • Organize files in a manner that makes it easy to associate them with specific courses (e.g., by course ID or name).

Step 2: Implement User Authentication in Next.js

1. Choose Authentication Method:

   • Use NextAuth.js for simplicity, or integrate with any auth service like Auth0, Firebase Auth, etc.

2. Setup Authentication:

   • Follow the setup instructions for your chosen method to implement authentication in your Next.js app.
   • Ensure you have user registration, login, and session management set up.

Step 3: Integrate Payment Gateway

1. Choose a Payment Gateway:

   • Options include Stripe, PayPal, etc. For this example, we'll assume Stripe.

2. Integrate Stripe:

   • Set up a Stripe account and get your API keys.
   • Implement the Stripe Checkout in your Next.js app to handle course purchases.
   • Use Stripe webhooks to listen for successful payments.

Step 4: Link Purchases with Access Rights

1. Database Setup:

   • Use a database (e.g., MongoDB, PostgreSQL) to store user purchases.
   • Create a schema that links users, their purchases, and the associated S3 video file paths or identifiers.

2. Access Management Logic:

   • After a successful purchase (confirmed via Stripe webhook), update your database to reflect the purchase and the user's access rights to the specific course content.

Step 5: Generate Secure URLs for Video Content

1. Create an API Endpoint:

   • In Next.js, create an API route (e.g., /pages/api/getVideo.js) that will handle requests for video content.

2. Verify User Access:

   • When a request is made to the API endpoint, verify the user's identity and their access rights to the requested video content by checking against your database.

3. Generate a Signed URL:

   • If the user has access, generate a presigned URL using the AWS SDK for JavaScript.
   • Presigned URLs provide temporary access to a private object in your bucket, perfect for securely serving private content.

// Example in an API route (/pages/api/getVideo.js)
import AWS from 'aws-sdk';
import { getSession } from 'next-auth/react'; // If using NextAuth.js

const s3 = new AWS.S3({
  accessKeyId: process.env.AWS_ACCESS_KEY_ID,
  secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY,
  region: process.env.AWS_REGION,
});

export default async function handler(req, res) {
  const session = await getSession({ req });
  if (!session) {
    return res.status(401).json({ error: 'Unauthorized' });
  }

  // Verify user access to the video here (omitted for brevity)

  const videoKey = 'path/to/video/in/s3.mp4'; // Determine based on the request/user
  const url = s3.getSignedUrl('getObject', {
    Bucket: process.env.YOUR_S3_BUCKET_NAME,
    Key: videoKey,
    Expires: 60 * 5, // URL expires in 5 minutes
  });

  res.status(200).json({ url });
}

Step 6: Frontend Video Access

1. Fetch Signed URL:

   • In your Next.js frontend, when a user tries to access a video, make a request to your API endpoint to get the presigned URL.

2. Play Video:

   • Use the obtained presigned URL as the source for a video player component (e.g., <video src={url} controls>).

Security Considerations

• Ensure that your S3 bucket is not publicly accessible and rely on presigned URLs for access.
• Validate user requests on your API endpoint thoroughly to prevent unauthorized access.
• Secure your application and API keys using environment variables and proper server-side security practices.