Exclude push event from ngsw-worker.js

EDIT(@gkalpak): Related to issue #24387.

I’m submitting a…

[ ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report  
[ ] Performance issue
[x ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead see https://github.com/angular/angular/blob/master/CONTRIBUTING.md#question
[ ] Other... Please describe:

Current behavior

I have my own service worker that listening push event. While building ngsw-worker.js auto generated and having push event available. Due to this website is showing notification two times. One from my service worker and another from ngsw-worker.js file.

Currently I have to comment that code each time I am building dist folder. Is there any option available that will automatically not include this push event listener?

this.scope.addEventListener('push', (event) => this.onPush(event));

Expected behavior

There should be option to not include this event.

Minimal reproduction of the problem with instructions

Problem required no plunkr. Its happening with PWA service worker js file.

Environment

Angular version: latest


Browser:
- [x] Chrome (desktop) version all
- [x] Chrome (Android) version all
- [x] Chrome (iOS) version all
- [x] Firefox version all
- [x] Safari (desktop) version all
- [x] Safari (iOS) version all
- [x] IE version all
- [x] Edge version all

[ghost]

This is still a pretty serious issue, partly because the implementation of push handling in ngsw is extremely limited. Because push events are broadcast to the SwPush instance in the browser, if the app is active, you can’t handle a push differently for active vs inactive apps. (For example, to trigger an action or show the notification in-app when the app is active, vs showing the desktop notification when it isn’t.)

A DIY service worker can have that logic present in it to say “this was dispatched to the application, don’t call showNotification(…)”.

There’s different ways this could be handled, but it seems all of the similar bug reports are from people trying to solve that underlying problem – if you use SwPush, you can’t prevent the native push, and if you use your own service worker, you get doubled up native notifications.

Given the scenarios people have are pretty varied, being able to simply turn off push support in ngsw seems like the better option, but at a minimum it seems like the ngsw implementation needs a way to tell it “if I have any clients, so this broadcast is going to hit an instance of my application, don’t show this notification”. Basically, if the broadcast() call in handlePush() actually posts any messages, don’t execute the code following it.

We’ve been trying to use Angular PWA, but this limitation is turning into a hard block for us, because the user experience for anything but the most trivial uses of push is just bad.

Something is fundamentally broken with the architecture if common use patterns are requiring people to hand edit the build output.

[shabbir-dhangot]

@gkalpak Can it be open? This is much needed feature who has already developed website. I am using firebase service-worker from months and that is having active notification listener.

Due to dual notification listener user is receiving notification twice. I appreciate if you introduce this option soon.

Currently managing with commenting line every-time.