122 is has google auth working on the web app (no work was needed as the google_sign_in plugin works out of the box on web)

sign_in_with_apple does not work for web out of the box, but they recommend a way to do it and it plan to add it at some point (though not soon), see: https://github.com/aboutyou/dart_packages/issues/90#issuecomment-637580587

From that comment the steps would be:

[ ] render the button in Flutter
[ ] use the same URL-building logic as on Android, see: https://github.com/aboutyou/dart_packages/blob/23679ba7e4b60d17f5ebe69f142fe94d813b7df7/packages/sign_in_with_apple/lib/src/sign_in_with_apple.dart#L198
[ ] on button click open that URL (redirect of the current page or pop-up/new tab (so main app doesn't have to reload on return)
[ ] set a route on your app as the redirect URL

Further notes from the linked comment:

the redirect URL would need to be able to handle the POST that Apple is sending to your servers
you can then either handle that directly on the server (and then for example pass down a cookie and the SPA entry page), or somehow pass received POST data to the client, so it would call the same API than the native apps do
as Apple is always redirecting through the redirect URL, I don't yet know how to make that really nice from a client API perspective (so that the same simple method could be called on all stacks)
maybe the pop-up / new tab approach can be made to work with the final redirect URL using postMessage to pass the data back to the Flutter app

adventures-in / chat_app