Support ZIM files with Service Worker

[kelson42]

New ZIMit based ZIM file use Service Worker.

[automactic]

TLDR: I don't think this is really possible right now.

In iOS 14, browser apps can become the default browser by using com.apple.developer.web-browser entitlement. (e.g. use Firefox as the default browser on iPhone) This AFAIK is the only way to have WkWebView support service workers right now.

Kiwix is not a generic purpose internet browser and cannot use this entitlement (I can positively say the app will be rejected if we do it), therefore there doesn't seem to be a way to support this request

See apple doc for more: link

[kelson42]

I have the same analysis. Kiwix is not a Web browser, therefore not concerned by the current "web browser app" approach.

This post is of interest as well https://dev.to/ben/will-ios-14-support-service-workers-in-wkwebview-5gn.

That said, the situation is evolving and it seems possible that WKWebView will support serive workers in the future.

For the moment, I believe this is important to ignore entries with the tag _sw:yes.

We will then re-evaluate the situation in a year.

[automactic]

ignore entries with the tag _sw:yes

Just to be clear: you mean not to show these files in the library right? What happens if user open such a file with kiwix?

[kelson42]

Yes this is what I mean. If open locally, the. The zim will display an error because it can itself detect that SW are not supported.

[automactic]

What happens if user try to manually open such a file?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[kelson42]

Not sure, but a message should be displayed that to be displayed this ZIM file needs service workers and this is not available.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[kelson42]

This ticket should better be updated because two years have passed.

[rgaudin]

Couldn't find a definitive answer online. Seems like it's available for app-bound-domains (a selection of up to 10 static domains you declare in the app) but I could not find any information regarding custom url scheme and service workers with WKWebView. Should probably be tested but lack of information online might demonstrate a lack of interest

[stephane-archer]

Do you think Mac Os has the same limitation as iOS? Do you have more alternatives than WKWebView?

[BenjaminJMueller]

Can we expect an update here in the following months? Would be highly appreciated if Zimit files would work on iOS and macOS soon.

[kelson42]

@rgaudin I have seen https://github.com/ionic-team/capacitor/issues/4122 which seems to confirm that SW are available for app-bounds-domain. That means that we could use such a bound-domain to allow SW:

• Either via a custom protocol handler (but SW has to work in that context)
• OR like we do on Kiwix for Android with our fake domain kiwix.app

[rgaudin]

Both needs to be tested as it's not guaranteed that it would be allowed

• We're not sure if SW would work with custom schemes. Security Context is HTTP specific
• We're not sure it it there's a mechanism similar to Andoid for intercepting requests shouldInterceptRequest and it it's as relaxed: we declare being on an HTTPS URL but we intercept/forge all requests (secure context here is not real)

[kelson42]

It seems that we will be able to create ZIM files without SW with Zimit in version 2.0. Therefore this feature request priority is significantly lowered.

[kelson42]

Closing as this won’t be necessary anymore once zimit2 will be released.