How to add offline support in Angular
Łukasz Holeczek
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Providing offline functionality ensures your Angular application remains usable even without an internet connection, improving user experience and reliability. As the creator of CoreUI, a widely used open-source UI library, I’ve implemented offline-capable applications throughout my 11 years of Angular development. The most effective approach is using Angular’s PWA package with service workers to cache assets and API responses. This method provides automatic caching strategies and seamless offline support with minimal configuration.
Add the @angular/pwa package to enable service worker-based offline support.
ng add @angular/pwa
Here the Angular CLI adds service worker configuration files including ngsw-config.json and registers the service worker in your app module. The configuration file defines caching strategies for static assets and API calls. The assetGroups section caches application files for offline access, while dataGroups configure runtime caching for dynamic data. Build the app with ng build --prod to generate the service worker, which intercepts network requests and serves cached content when offline.
Best Practice Note:
This is the same pattern we recommend for CoreUI Angular applications requiring offline capabilities in enterprise environments. Always test offline behavior thoroughly, as service workers cache aggressively and can make debugging difficult during development without proper cache invalidation strategies.
