Currently a bug exists where attempting to inject SwPush crashes the
application if Service Workers are unsupported. This happens because
SwPush doesn't properly detect that navigator.serviceWorker isn't
set.
This change ensures that all passive observation of SwPush and
SwUpdate doesn't cause crashes, and that calling methods to perform
actions on them results in rejected Promises. It's up to applications
to detect when those services are not available, and refrain from
attempting to use them.
To that end, this change also adds an `isSupported` getter to both
services, so users don't have to rely on feature detection directly
with browser APIs. Currently this simply detects whether the SW API
is present, but in the future it will be expanded to detect whether
a particular browser supports specific APIs (such as push
notifications, for example).
Currently, the way to not use the SW is to not install its module.
However, this means that you can't inject any of its services.
This change adds a ServiceWorkerModule.disabled() MWP, that still
registers all of the right providers but acts as if the browser does
not support Service Workers.
This commit fixes several issues discovered through use in real apps.
* The sha1() function operated on text content, causing issues for binary-format files.
A sha1Binary() function which operates on unparsed data now avoids any encoding issues.
* The characters '?' and '+' were not escaped in Glob-to-regex conversion previously, but
are now.
* URLs from the browser contain the full origin, but were checked against the table of
hashes from the manifest which only has the path for URLs from the same origin. Now the
origin is checked and URLs are relativized to the domain root before comparison if
appropriate.
* ngsw: prefix was missing from data groups, is now added.
* Occasionally servers will return a redirected response for an asset, and caching it could
cause errors for navigation requests. The SW now handles this by detecting such responses
and following the redirect manually, to avoid caching a redirected response.
* The request for known assets is now created from scratch from the URL before fetching from
the network, in order to sanitize it and avoid carrying any special modes or headers that
might result in opaque responses.
* Debugging log for troubleshooting.
* Avoid creating errors by returning 504 responses on error.
* Fix bug where idle queue doesn't run in some circumstances.
* Add tests for the above.
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.
Alex Rickabaugh