Advanced PWA Performance Topic 19

Introduction

In this lesson, we will explore advanced performance optimizations for Progressive Web Apps (PWAs). Performance is crucial for user engagement and retention, and adopting best practices can significantly enhance the user experience.

Key Concepts

• Service Workers: Background scripts that cache resources and manage offline capabilities.
• Lazy Loading: Loading resources only when they are needed.
• Code Splitting: Dividing code into smaller chunks to load on demand.
• Optimization Techniques: Using tools like Lighthouse to assess and improve performance.

Best Practices

1. Implement a Service Worker for caching and offline support.
2. Use lazy loading for images and other media to reduce initial load times.
3. Optimize images and assets (e.g., using WebP format, compression).
4. Minimize the use of blocking resources (CSS, JavaScript) in the head.
5. Leverage HTTP/2 for faster resource loading.
6. Use Content Delivery Networks (CDNs) for static assets.
7. Monitor performance regularly using analytics tools.

Code Examples

Service Worker Example

                self.addEventListener('install', (event) => {
                    event.waitUntil(
                        caches.open('my-cache').then((cache) => {
                            return cache.addAll([
                                '/',
                                '/index.html',
                                '/styles.css',
                                '/script.js',
                            ]);
                        })
                    );
                });

                self.addEventListener('fetch', (event) => {
                    event.respondWith(
                        caches.match(event.request).then((response) => {
                            return response || fetch(event.request);
                        })
                    );
                });
                

FAQ