Saving once in airplane mode breaks future cloud sync (Android)

[JVimes]

Syncing between Android devices generally works, but if I put the first device into airplane mode and do a save, then go back online, subsequent (online) saves do not make it to the second device.

• Restarting the app and clearing local app storage did not help.
• I am still able to sync the other direction (second device to first) and this seems to fix syncing first-to-second.
• I'm able to repro in my game and in ChooseSave.
• I don't see the issue when using the Google Play Games Services plugin directly (not using unity-cloud-save) in one of my other games.

Any ideas? 🫤

[gilzoide]

Well, that's weird. I don't have any ideas right now.

I don't see the issue when using the Google Play Games Services plugin directly (not using unity-cloud-save) in one of my other games.

Hmm, maybe you can help spotting what's different between the implementations. Or if you send me how you implemented it without the problem, it would help me to take a look directly into a working vs not working scenario to find what could be the problem.

[gilzoide]

Oh, and of course, thanks a lot for the bug report @JVimes!

[JVimes]

I'm happy to try to help 🙂 I've never coded for native libraries before.

Here's the source code of the method I'm calling to save bytes. I see commitAndClose there. In your code I see CommitUpdate. Maybe that difference is significant?

If that source code does not shine any light, let me know and I'll put together a sample app.

Also, the Google plugin has a smoke test app. I haven't tried it, though.

[JVimes]

Regarding my game that doesn't have the issue, it looks like the difference is probably in my code and not Google's. I wrote a simple save/load app that calls the same Google methods, passing the same arguments, and the issue appeared. I'll try to incrementally mutate the game into the save/load app to figure out what specifically brings on the issue.

[JVimes]

Alright, I narrowed down what my game is doing differently and demoed it in SaveSample.

If you can, please take a look at this commit, which works around the issue. Two things were required:

1. It saves twice
2. The first save lacks await

That last point confuses me.

[JVimes]

I reported the issue to Google here, but I don't have high hopes that they read issue reports. 🤷

[JVimes]

I was able to repro without an event and updated my above comment. Still a very strange workaround. It requires breaking the await chain.