fix: Safely and lazily initialize native RNSkia JSI Bindings

[mrousavy]

The current way RNSkia JSI Bindings are installed is unsafe and actually crashes in Release builds on Android, since it is not following JSI Runtimes Threading Guidelines.

A JSI Runtime has no Thread Safety, and RNSkia does not enforce initial JSI Runtime operations (install the SkiaApi global) to run on the JS Thread, and since they are called when the RN Skia Module initializes, they are actually ran on the Native Module (mqt_native/mqt_nm) Thread, which leads to crashes since the Runtime might not be available yet.

This PR changes this behavior to expose a install(...) function that uses React Native's "blocking synchronous" native module function API, which as I initially expected, executes on the JS Thread (it's blocking.). This function is then called in the top-level index.ts file.

Benefits

• Doesn't randomly crash on iOS release builds anymore
• Doesn't randomly crash on Android release builds anymore
• Seems to be safer and more predictable because we install the API just before we use it
• A bit more lazy since the JSI Bindings only get installed once the react-native-skia package is imported, as opposed to eagerly install on app launch

[chrfalch]

This looks awesome! Will test and verify very soon!

[mrousavy]

Cool - as discussed on Slack, it works for me on iOS. I unfortunately couldn't build Android, but I think the code is right. Feel free to DM me to troubleshoot if something isn't working there.

[chrfalch]

Cool - as discussed on Slack, it works for me on iOS. I unfortunately couldn't build Android, but I think the code is right. Feel free to DM me to troubleshoot if something isn't working there.

I'll test on both platforms to make sure it is working. Thanks so much!! <3

[chrfalch]

Fixed a missing import on Android (ReactMethod), and merged with main.

[chrfalch]

Upgraded with latest from main, fixed missing import on Android.

Tested on both Android/iOS and it works fine.

[axeldelafosse]

Woohoo! Thanks Marc!

[mrousavy]

glad it works out so well, can't believe I didn't discover this sooner for MMKV 🙈

[rvasseur31]

You can replace it with :

if (!global.SkiaApi) {
  // Initialize RN Skia
  const SkiaModule = NativeModules.RNSkia;
  if (!SkiaModule || typeof SkiaModule.install !== "function") {
    throw new Error(
      "Native RNSkia Module cannot be found! Make sure you correctly " +
        "installed native dependencies and rebuilt your app."
    );
  }
  const result = SkiaModule.install();
  if (!result) {
    throw new Error(
      `Native Skia Module failed to correctly install JSI Bindings! Result: ${result}`
    );
  }
}

[mrousavy]

lol I know that I can, but I won't because those implicit boolean checks are hard to read.

[chrfalch]

glad it works out so well, can't believe I didn't discover this sooner for MMKV 🙈

This will become the new pattern for safely initialising JSI Modules!!!