iCloud: Key-value storage is inadequate

[ChrisNZL]

Auto reports from 0.3.6 on iOS. Feedback ID: 20220930-YS6FV

ERROR »  Unable to save to cloud. Key-value store has exeeded its space quota on the iCloud server.

• It seems the iCloud key-value storage Tallowmere 2 v0.3.6 currently uses (in conjunction with CloudOnce) is limited to 1 MB per user account.
• This might be okay initially, but a single saved game (after reaching many rooms), or having multiple saved games, will eventually exceed this 1 MB limit.

Tasks:

• Investigate switching iCloud storage to one of the following:
  • iCloud Documents
  • CloudKit
  • iCloud Containers
    

[ChrisNZL]

Improvements made in 0.3.6b on iOS to address this:

• Account file strips pending leaderboard score entries of unnecessary data before uploading to tallowmere2.com – this isn't fully utilised yet for iOS (for leaderboard entries), so for now, just doing this temporary measure to reduce chance of the user's account exceeding 1 MB.

Next step:

• Try to use iCloud Containers or something as mentioned above.

[ChrisNZL]

Existing Unity plugins

Cross-Platform Native Plugins (Voxel Busters)

• ❌ Only supports iCloud Key-value storage

prime31 iCloud Plugin

• 🔶 Its documentation says it has CloudKit support, but from the reviews (and lack of recent releases), sounds like it's buggy and won't compile from the get-go.

HovelHouse iCloud and CloudKit Plugin

• 🔶 Supports CloudKit, but has compiler issues, and a lack of support.

IOS Native Pro (Stan's Assets)

• 🔶 Supports CloudKit.
• 🔶 Lack of support from the developer, according to reviews.
• 🔶 I've dabbled with this plugin a long time ago, back on Tallowmere 1. API has lots of spelling mistakes; usages of SingIn, for example. I seem to recall a large update / refactor that broke pretty much everything as well at one point, which is when I switched to CloudOnce.

Summary

I don't fancy writing my own Objective-C / Swift plugin for using iCloud Containers (CloudKit) if I can help it.

iCloud Key-value storage seems to work okay "most" of the time, though the 1 MB account limit isn't the best.

Other plugins sound too problematic to pursue ditching CloudOnce.

Next steps

The 1 MB limit is potentially a blocker in the long-run. For now, need to try and work around it:

• Refactor the Account.t2 file:
  • Move pending leaderboard submissions to a new file: PendingLeaderboardEntries.t2
  • Do not have PendingLeaderboardEntries.t2 be cloud-syncable on iOS.
  • Restore / retain full debug info for pending leaderboard submissions for iOS, rather than stripping them.
  • For iOS, investigate compressing the various .t2 files before converting to Base64.

[ChrisNZL]

Or...

Just discovered there is a CloudKit Web Services API, which means I don't have to use a plugin, nor learn Objective-C / Swift – can just use HTTP requests instead.

• CloudKit Web Services Reference
• CloudKit Documentation

... or not. Authenticating using the Web Services API requires signing into Apple using a web view or web browser, which is inappropriate for an iOS game.

---

Not going to pursue writing my own Swift nor Objective-C plugin. Outside my expertise; not worth my time right now.

Found an official Apple repository for Unity plugins, but there is no plugin for iCloud right now. Submitted a request to Apple via Feedback Assistant.

[ChrisNZL]

For 0.3.7o on iOS (long as Apple approves this):

• New games, and saving games, now uses local storage instead of the iCloud key-value system.

• Where possible, the game will download saved games from the key-value system, and then delete them from the key-value system (to ensure the 1 MB limit does not get reached).