Service Workers can be tricky to work with in production, and often
it becomes necessary to deactivate an existing SW. This is trickier
than one might imagine - as long as clients on the old SW may exist
it is important to serve some script at the old SW URL. This commit
adds safety-worker.js to the published NPM package, which is useful
for that purpose. On install the SW unregisters itself which safely
and gradually allows older clients to update.
PR Close#21863
This service worker is a conceptual derivative of the existing @angular/service-worker maintained at github.com/angular/mobile-toolkit, but has been rewritten to support use across a much wider variety of applications.
Entrypoints include:
@angular/service-worker: a library for use within Angular client apps to communicate with the service worker.
@angular/service-worker/gen: a library for generating ngsw.json files from glob-based SW config files.
@angular/service-worker/ngsw-worker.js: the bundled service worker script itself.
@angular/service-worker/ngsw-cli.js: a CLI tool for generating ngsw.json files from glob-based SW config files.