Django: serve apple-app-site-association and assetlinks.json

If your site has companion Apple or Android apps, you probably want links to your site to open in those apps, when installed. Both platforms support this, with Apple calling the feature Universal Links and Android calling it App Links. But an app can’t just claim to handle your links, or any malicious app could hijack them. Instead, both platforms require two-way association: the app declares which domains it handles, and each domain confirms which apps may handle its links. The domain’s side of that handshake is a JSON file served under the reserved /.well-known/ path, one per platform: /.well-known/apple-app-site-association for iOS, iPadOS, and macOS. /.well-known/assetlinks.json for Android. These files can do more than link handling. Both can also associate apps with your site for password autofill and passkeys, so users can sign in to your apps with credentials saved from your site. In this post, we’ll look at serving these two files from Django, with tests. It follows the same…