PWA Fundamentals Topic 24

Introduction

Progressive Web Apps (PWAs) are web applications that provide a native app-like experience on the web. They combine the best of web and mobile apps, enabling users to enjoy fast, reliable, and engaging experiences.

Key Concepts

• Service Workers: A script that the browser runs in the background, separate from a web page, allowing features like push notifications and offline capabilities.
• Web App Manifest: A JSON file that provides the necessary metadata for the PWA, including the app name, icons, start URL, and display options.
• Responsive Design: Ensuring the app works seamlessly on various devices and screen sizes.
• HTTPS: PWAs must be served over HTTPS to ensure security and integrity.

Code Example

if ('serviceWorker' in navigator) {
    window.addEventListener('load', () => {
        navigator.serviceWorker.register('/service-worker.js')
            .then(registration => {
                console.log('Service Worker registered with scope:', registration.scope);
            })
            .catch(error => {
                console.error('Service Worker registration failed:', error);
            });
    });
}
                

Best Practices

1. Always serve your PWA over HTTPS.
2. Implement service workers for offline capabilities.
3. Use a web app manifest for installation on mobile devices.
4. Make sure your app is responsive and accessible.
5. Utilize caching strategies to enhance performance.

FAQ

Service Worker Lifecycle

graph TD;
    A[Install] --> B[Activate];
    B --> C[Fetch];
    C --> D[Cache];
    D --> E[Update];
    E --> B;