Async API doesn't work on WebGL platform

[JohannesNicholas]

Hi Gilzoide!
I have been experimenting with the package and it has been working well!

Async on WebGL doesn't not appear to work. I believe this is due to SQLite-net using Task.Factory.StartNew.

I'm using Unity 2022

Unsure what the best solution for this would be, I believe there are options for doing threading on WebGL but for now I might stick to non-async queries.

[gilzoide]

Hey @JohannesNicholas.

I have been experimenting with the package and it has been working well!

Nice, glad to hear it's working well ^^

I believe this is due to SQLite-net using Task.Factory.StartNew.

Yeah, that's most likely it. Unity WebGL builds don't support threading, although they do support async if it doesn't use any background threading.

My suggestion is to just use the synchronous API on WebGL (maybe on all other platforms as well for simplicity). SQLite is usually fast enough and with the correct usage of indexes and transactions, even more so.
In general I'd say unless you are reading/storing huge amounts of data into your database or running hundreds of queries without an explicit transaction, you should be fine. Of course, if you have a bottleneck or worry you might have one, profile your build.

We could also actually support the async API in WebGL by changing the TaskScheduler used in TaskFactory.StartNew, instead of using TaskScheduler.Default which runs tasks on a thread pool, we could use TaskScheduler.FromCurrentSynchronizationContext() from the main thread, so that tasks actually run on Unity's main thread. I like this idea actually, even if this async won't really run on background threads and only adds overhead to the application on WebGL, at least people could use the async API in all platforms and not have to make workarounds with #if UNITY_WEBGL.

[gilzoide]

Hey @JohannesNicholas, so I fixed async support for WebGL builds, it's available in the newly released version 1.1.2 \o/

I still would recommend using the synchronous API and only resorting to the async one if you profile your build and verify that SQLite usage is a bottleneck. On WebGL there will only be overhead and no background threading, and on other platforms you get more complexity of async flows on something that might not influence frame time enough to be worth it.

[JohannesNicholas]

Thank you! Have tested out the async API and it works perfectly!

[gilzoide]

Glad to hear that it worked for you!

Cheers \o/