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 helps ensure we use the same tsconfig.json file for all compilations.
Next steps are to make it the same tsconfig.json file used by the editor
PR Close#20964
When the SW fetches URLs listed in a manifest with hashes, it checks
the content hash against the manifest to make sure it has the correct
version of the URL. In the event of a mismatch, the SW is supposed to
consider the manifest invalid, and avoid using it. There are 3 cases
to consider by which this can happen.
Case 1: during the initial SW installation, a manifest is activated
without waiting for every URL to be fully loaded. In the background,
every prefetch URL listed by the manifest is requested and cached.
One such prefetch request could fail the hash test, and cause the
manifest to be treated as invalid. In such a case, the SW should
enter a state of EXISTING_CLIENTS_ONLY, as the latest manifest is
invalid.
This case works today.
Case 2: during the initial SW installation, as in Case 1, a manifest
is activated without waiting for each URL to fully load. However,
it's possible that the application could request a URL with a bad
hash before background initialization tries to load that URL. This
happens if, for example, the application has a broken index.html.
In this case, the SW should enter a state of EXISTING_CLIENTS_ONLY,
and serve the request from the network instead.
What happens today is that the internal error escapes the SW and
is returned as a rejected Promise to respondWith(), causing a
browser-level error that the site cannot be loaded, breaking the
site.
This change allows the SW to detect the error and enter the correct
state, falling back on the network if needed.
Case 3: during checkForUpdate(), the SW will try to fully cache the
new update before making it the latest version. Failure here is
complicated - if the page fails to load due to transient network
conditions (timeouts, 500s, etc), then it makes sense to continue
serving the existing cached version, and attempt to activate the
update on the next cycle.
If the page fails due to non-transient conditions though (400 error,
hash mismatch, etc), then the SW should consider the updated
manifest invalid, and enter a state of EXISTING_CLIENTS_ONLY.
Currently, all errors are treated as transient.
This change causes the SW to treat all errors during updates as
non-transient, which can cause the SW to unnecessarily enter a
safe mode. A future change can allow the SW to remain in normal mode
if the error is provably transient.
PR Close#21288
- Add tests target for `test`, `test_node_only` and `test_web` in `core` package.
- Created a `_testing_init` pseudo package where bootstrap code for tests is kept.
- Moved `source_map_util` from `test` to `testing` so to prevent circular dependency.
- Removed `visibility:public` for testing `BUILD` packages.
PR Close#21053
Currently the Service Worker checks for updates only on SW startup,
an event which happens frequently but also nondeterministically. This
makes it hard for developers to observe the update process or reason
about how updates will be delivered to users. This problem is
exacerbated by the DevTools behavior of keeping the SW alive
indefinitely while opened, effectively preventing the page from
updating at all.
This change causes the SW to additionally check for updates on
navigation requests (app page reloads). This creates deterministic
update behavior, and is much easier for developers to reason about.
It does leave the old update-on-SW-startup behavior in place, as
removing that would be a breaking change.
Fixes#20877
Add enough BUILD files to make it possible to
`bazel build packages/core/test`
Also re-format BUILD.bazel files with Buildifier.
Add a CI lint check that they stay formatted.
PR Close#20768
The package.json esm2015 points to the wrong path.
"esm15" should be "esm2015"
Service Worker can't be compiled with use of Closure Compiler
PR Close#20800
Not every application is served from the domain root. The Service
Worker made a bad assumption that it would be, and so requested
/ngsw.json from the domain root.
This change corrects this assumption, and requests ngsw.json without
the leading slash. This causes the request to be interpreted
relative to the SW origin, which will be the application root.
The Service Worker contains a mechanism by which it will postMessage
itself a signal to initialize its caches. Through this mechanism,
initialization happens asynchronously while keeping the SW process
alive.
Unfortunately in Firefox, the SW does not have the ability to
postMessage itself during the activation event. This prevents the
above mechanism from working, and the SW initializes on the next
fetch event, which is often too late.
Therefore, this change has the application wait for SW changes and
tells each new SW to initialize itself. This happens in addition to
the self-signal that the SW attempts to send (as self-signaling is
more reliable). That way even on browsers such as Firefox,
initialization happens eagerly.
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.
Observable.merge was called using .call() as if it were an operator
and not an Observable factory. This removes the .call() and uses
the factory properly.
PR Close#19962
Importing ServiceWorkerModule.register() will schedule registration of
the Service Worker inside an APP_INITIALIZER. Previously, the Promise
returned by navigator.serviceWorker.register() was returned from the
initializer function. This has the unwanted side effect of blocking
initialization until the SW is registered. Even worse, if the SW script
fails to load, this can cause the app initialization to fail.
The solution is to not return the registration promise from the
initializer function, essentially decoupling registration from the rest
of the initialization flow.
This change is not unit testable as there are no mocks/adapters yet for
navigator.serviceWorker. A future integration test should cover this case
with better fidelity.
PR Close#19936
Currently, the SwUpdate service doesn't receive messages from the SW.
This is because it attempts to subscribe to the 'message' event on
ServiceWorkerRegistration, when really messages are emitted by the
ServiceWorkerContainer.
This change moves to listening on ServiceWorkerContainer and changes
the mocks to reflect the way the browser actually works.
PR Close#19954
There is no difference in runtime (yet) between versioned and unversioned
files. Theoretically, the SW does not have to cache-bust versioned files,
but the SW doesn't cache bust files on the first request anyway, so in the
common case it doesn't matter. If the hash doesn't match, the SW will cache
bust the file to be sure, which is technically unnecessary, but since the
file itself is versioned, the likelihood of this happening is rare.
This fixes a critical bug where versioned files were erroneously not included
in the hashTable in the generated manifest. This could lead to applications
not updating if only versioned files changed in between versions.
PR Close#19837
PushEvent.data is not the data object itself, but an instance representing
the data in wire format, with methods to synchronously decode it to JSON,
ArrayBuffer, etc. NGSW assumes all push data is in JSON format.
PR Close#19764
When Cache.put() is called with a Response, it consumes the response. If
the Response is used for any other purpose (such as satisfying the
original FetchEvent) it must be cloned first.
A bug exists in the mocks used for SW tests, where this condition is not
validated. The bodies of MockResponses can be utilized repeatedly without
erroring in the same way that a real browser would. This bug is fixed by
this commit, which causes tests for the freshness strategy of data caching
to start failing.
The cause of this failure is a second bug in the data caching code, where
the Response is not cloned prior to being passed to Cache.put(). This is
also fixed.
PR Close#19764
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
Alex Eagle
Chuck Jazdzewski
Miško Hevery
Fabian Wiles
Mathias Døhl
Hans Larsen
Vohmyanin Sergey Vasilevich
Trotyl