Editing Angular (section)

===PWA===
Progressive Web Apps (PWA) rely on '''Service Workers'''. Service workers essentially act as proxy servers that sit between web applications, the browser, and the network (when available). They are intended, among other things, to enable the creation of effective offline experiences, intercept network requests and take appropriate action based on whether the network is available, and update assets residing on the server. They will also allow access to push notifications and background sync APIs.

When an application is loaded it is provided from the cache. In the background the service worker checks for an update and loads it to the cache. The new one is used next time the application is loaded. The version information is generated during build in <code>ngsw.json</code>.

====Implementation====
* [https://blog.angular-university.io/angular-service-worker/ Angular University detailed step by step guide] or
* [https://morioh.com/p/984afc91af1c The complete Guide to Service Workers]
* Progressive Web App (PWA)
 ng add @angular/pwa
* creates e.g. <code>ngsw-config.json</code> which format is described [https://angular-doc.ru/guide/service-worker-config here]

=====Debug Information=====
* [https://angular.io/guide/service-worker-devops#locating-and-analyzing-debugging-information description]
* see http://<URL>:<PORT>/ngsw/state e.g. http://127.0.0.1:8082/ngsw/state output
 [=== Version <HASH>
 Clients ... // clients with this version, could also be different tabs]

=====Version Management=====
[https://stackoverflow.com/questions/61042675/angular-pwa-update-is-too-slow Here] is a solution if the version update should be done immediately when the application is loaded.