Vault Architecture

[wittjosiah]

Problem

Web browsers are trending more and more towards not allowing shared data between origins [1] [2] [3] which stops one of the biggest motivations of the vault architecture [4]: a shared database instance between multiple applications.

Notes

• currently wherever possible DXOS apps will run the client services in an iframe which allows the database to be shared between all apps
• this is already not possible in Safari and soon will not be possible in Chrome
• we still think the vault architecture itself is worth exploring but it's likely a longer term exploration, and likely needs to happen outside the browser
  • native app could host a server on local host which acts a vault
  • maybe there's a web extension that helps to bridge that into the browser
• in the browser, the client services probably still run in a shared worker (but just on the apps domain) because that's the best way to share the db between multiple tabs
• one benefit of not using the iframed vault is that there would no longer be a nested PWA/Service Worker cache to try to deal with as updates role out

References

[1] https://developer.chrome.com/docs/privacy-sandbox/shared-storage/
[2] https://webkit.org/tracking-prevention/
[3] https://social.coop/@josiah/110374222202958196
[4] https://github.com/dxos/dxos/blob/f0cd5328c14a7fc2f573f91e5fbc26b67d031a9a/docs/docs/design/diagrams/client-services.drawio.svg

[wittjosiah]

As noted above, at present we're primarily using vault modes of operation

We're currently looking at shifting to something much simpler soon

Notes:

• no cross-domain barrier helps us avoid the issues stated above
• no cross-domain barrier means that the only way apps will share data is via device invitations between them for the time being
  • later we expect the vault architecture to re-emerge, with a native app serving as the vault
• monolithic mode already exists today, but does not work well with shell
• the pieces for worker mode all exist today in vault mode, they just need to be put together differently
• the new modes of operation are overall simpler and hopefully will be more intuitive for developers and easier to debug

[wittjosiah]

We've now completed the transition to the simpler non-iframe setup. This PR #4769 was where the bulk of those changes landed to the main branch (followed by many bug fixes & improvements). These changes will roll out in the 0.4.0 release in the near future.