How to Convert Video of a Web App into a React App and Implement Authentication with Auth0

TL;DR: This article demonstrates how to leverage Replay, a video-to-code engine, to convert a screen recording of a web application into a functional React app with Auth0 authentication, focusing on behavior-driven reconstruction.

From Video to React App: A Behavior-Driven Approach#

The traditional approach to building UIs often involves manual coding, design iterations, and constant back-and-forth between design and development teams. What if you could capture the essence of a working application simply by recording its usage and then automatically generate the code? This is where Replay comes in, offering a revolutionary approach to UI development.

Replay utilizes video analysis powered by Gemini to reconstruct UI code based on observed user behavior. Unlike screenshot-to-code tools that only capture visual elements, Replay understands what users are trying to achieve, enabling the generation of more robust and context-aware applications. In this guide, we'll walk through converting a video of a web app into a React application with Auth0 authentication, showcasing Replay's capabilities.

Understanding Behavior-Driven Reconstruction#

Replay's core innovation lies in its ability to perform Behavior-Driven Reconstruction. This means the system analyzes the video not just for visual elements, but also for the sequence of actions, interactions, and data flow. This allows Replay to generate code that accurately reflects the intended functionality of the application.

Here's a comparison of Replay against traditional and screenshot-based methods:

Converting a Web App Video to a React App with Auth0#

Let's assume we have a screen recording of a simple web application showcasing user registration, login, and profile viewing. Our goal is to convert this video into a functional React application with Auth0 integration.

Step 1: Upload and Analyze the Video with Replay#

First, upload the video to the Replay platform. Replay will then analyze the video, identifying UI elements, user interactions (e.g., button clicks, form submissions), and data flow. This process might take a few minutes depending on the length and complexity of the video.

💡 Pro Tip: Ensure the video is clear and contains distinct user interactions for optimal analysis by Replay.

Step 2: Configure Replay Settings#

Once the analysis is complete, you'll be presented with a visual representation of the application flow. Here, you can configure several settings:

• •Framework: Select "React" as the target framework.
• •State Management: Choose a state management library if needed (e.g., Redux, Zustand). For this example, we'll stick with React's built-in
  text

  useState
  hook for simplicity.
• •Authentication: Enable Auth0 integration. Replay will prompt you to provide your Auth0 domain, client ID, and client secret.

Step 3: Generate the Code#

With the settings configured, initiate the code generation process. Replay will then generate the React application code, including:

• •React components for each screen in the video.
• •Event handlers for user interactions.
• •Auth0 authentication logic.
• •Basic styling based on the visual elements in the video.

Step 4: Integrate Auth0 Authentication#

Replay automatically generates the basic Auth0 integration, but you might need to refine it further. Here's a snippet of the generated code for handling user login:

typescript
// src/components/Login.tsx
import React from 'react';
import { useAuth0 } from '@auth0/auth0-react';

const LoginButton = () => {
  const { loginWithRedirect } = useAuth0();

  return (
    <button onClick={() => loginWithRedirect()}>
      Log In
    </button>
  );
};

export default LoginButton;

You'll need to install the Auth0 React SDK:

bash
npm install @auth0/auth0-react

And wrap your application with the

:

typescript
// src/index.tsx
import React from 'react';
import ReactDOM from 'react-dom/client';
import App from './App';
import { Auth0Provider } from '@auth0/auth0-react';

const root = ReactDOM.createRoot(document.getElementById('root'));

root.render(
  <Auth0Provider
    domain="YOUR_AUTH0_DOMAIN"
    clientId="YOUR_AUTH0_CLIENT_ID"
    redirectUri={window.location.origin}
  >
    <App />
  </Auth0Provider>
);

Replace

and with your actual Auth0 credentials.

📝 Note: Replay can often infer API endpoints from the video if network requests are visible. However, you might need to manually configure these endpoints or connect to a backend service like Supabase.

Step 5: Customize and Refine the Code#

While Replay generates a functional application, you'll likely need to customize and refine the code to meet your specific requirements. This might involve:

• •Improving the styling.
• •Adding more complex logic.
• •Connecting to external APIs.
• •Optimizing performance.

Replay's generated code serves as a solid foundation, saving you significant development time and effort.

Replay's Key Features in Action#

Here's how Replay's key features contribute to this process:

• •Multi-page Generation: Replay automatically identifies and generates components for each page or screen in the video, ensuring a complete application structure.
• •Supabase Integration: If your application interacts with a Supabase database (and the video shows this interaction), Replay can generate the necessary code to connect to your Supabase instance.
• •Style Injection: Replay attempts to infer styling from the video and inject it into the generated components, providing a visually consistent application.
• •Product Flow Maps: Replay creates a visual map of the application flow based on the video, allowing you to easily understand and modify the application's navigation.

Benefits of Using Replay#

• •Rapid Prototyping: Quickly create functional prototypes from existing application demos or user recordings.
• •Reduced Development Time: Automate the generation of UI code, freeing up developers to focus on more complex tasks.
• •Improved Accuracy: Behavior-Driven Reconstruction ensures the generated code accurately reflects the intended functionality of the application.
• •Enhanced Collaboration: Easily share and iterate on application prototypes with stakeholders.

⚠️ Warning: Replay is not a replacement for skilled developers. It's a powerful tool that can significantly accelerate the development process, but human oversight and customization are still essential.

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited functionality. Paid plans are available for more advanced features and higher usage limits. Check the Replay website for current pricing information.

How is Replay different from v0.dev?#

While both Replay and v0.dev aim to automate UI development, they differ in their input methods and underlying technology. v0.dev typically uses text prompts or design files as input, whereas Replay analyzes video recordings. Replay's behavior-driven reconstruction allows it to understand user intent, leading to more accurate and functional code generation.

What types of applications can Replay handle?#

Replay can handle a wide range of web applications, from simple landing pages to complex e-commerce platforms. The quality of the video recording and the clarity of user interactions are key factors in determining the accuracy of the generated code.

Can Replay generate backend code?#

Currently, Replay primarily focuses on generating frontend UI code. However, it can infer API endpoints and data models from the video, which can be used as a starting point for developing backend services. Integration with services like Supabase further bridges the gap between frontend and backend development.

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Ready to try behavior-driven code generation? Get started with Replay - transform any video into working code in seconds.