Support callback for Service worker registration

[SwaroopH]

According to The Service Worker Lifecycle, Sapper (without push/sync) seems to never trigger an update.

I see that the service worker script is injected directly making it hard to customize the callback.

I am trying to build a "version check" thing. I customized the service worker to handle some of the stuff but since I do not have the callback/promise to work with, it's tough to trigger this without modifying the sapper base to something like this:

if (has_service_worker) {
	script += `if('serviceWorker' in navigator)navigator.serviceWorker.register('${req.baseUrl}/service-worker.js').then(reg => {
		setInterval(() => {
			console.log('checking sw update');
			reg.update()
		}, 3600000);
	});`;
}

One other way could be is to remove the hard check on has_service_worker and allow users to write their own implementation.

Let me know if it makes sense.

[julienchazal]

Hello, is this feature will be implemented soon ?
I'm trying to add Firebase Cloud Messaging to Sapper but i need to have a callback for sw registration too please.
See FCM doc
Thx

[julienchazal]

Anybody ?

[SwaroopH]

@julienchazal Feel free to pull this change from my fork: a9d1259 - we are using it in production.

[julienchazal]

thanks @SwaroopH , did you make a PR ?

[SwaroopH]

@julienchazal not yet since I hadn't heard from the maintainers.

[treyssatvincent]

You can have a service worker registration callback like this :

navigator.serviceWorker.ready.then(registration => console.log(registration))

Just replace the console.log(registration) by your callback.

[antony]

@SwaroopH what feedback are you looking for specifically?

[SwaroopH]

@antony just wanted to know if it's the right approach. Happy to rebase and make a PR. We've been using this in production on multiple products for over a year :)