**Problem**
After #31109 and #31865, it's still possible to get locked in state
`EXISTING_CLIENTS_ONLY`, without any possibility to get out (even by
pushing new updates on the server).
More specifically, if control doc `/latest` of `ngsw:/:db:control` once
gets a bad value, then the service worker will fail early, and won't be
able to overwrite `/latest` with new, valid values (the ones from future
updates).
For example, once in this state, URL `/ngsw/state` will show:
NGSW Debug Info:
Driver state: EXISTING_CLIENTS_ONLY (Degraded due to failed initialization: Invariant violated (initialize): latest hash 8b75… has no known manifest
Error: Invariant violated (initialize): latest hash 8b75… has no known manifest
at Driver.<anonymous> (https://my.app/ngsw-worker.js:2302:27)
at Generator.next (<anonymous>)
at fulfilled (https://my.app/ngsw-worker.js:175:62))
Latest manifest hash: 8b75…
Last update check: 22s971u
... with hash `8b75…` corresponding to no installed version.
**Solution**
Currently, when such a case happens, the service worker [simply fails
with an assertion][1]. Because this failure happens early, and is not
handled, the service worker is not able to update `/latest` to new
installed app versions.
I propose to detect this corrupted case (a `latest` hash that doesn't
match any installed version) a few lines above, so that the service
worker can correctly call its [already existing cleaning code][2].
[1]: https://github.com/angular/angular/blob/3569fdf/packages/service-worker/worker/src/driver.ts#L559-L563
[2]: https://github.com/angular/angular/blob/3569fdf/packages/service-worker/worker/src/driver.ts#L505-L519
This change successfully fixes the problem described above.
Unit test written with the help of George Kalpakas. Thank you!
PR Close#37453
d63ecf4c5f