Reading meta-data values

[ajayjapan]

I'm having trouble with reading config from the Android side. The iOS path works via Bundle.main.object(forInfoDictionaryKey:), but on Android Bundle.main.packageInfo.metaData?.get(key) (inside the #if SKIP branch) isn’t returning values.

Relevant snippet:

public enum AppConfiguration {
  public enum Error: Swift.Error {
    case missingKey, invalidValue
  }
  
  public static func value<T>(for key: String) throws -> T where T: LosslessStringConvertible {
    
#if !SKIP
    // ios portion
    let object = Bundle.main.object(forInfoDictionaryKey:key)
#else
//    let context = ProcessInfo.processInfo.androidContext
//    let packageManager = context.getPackageManager()
//    let packageInfo = packageManager.getApplicationInfo(context.getPackageName(), android.content.pm.PackageManager.GET_META_DATA)
    let packageInfo = Bundle.main.packageInfo
    let object = packageInfo.metaData?.get(key)
#endif
    
    guard let object else {
      throw Error.missingKey
    }
    
    switch object {
    case let value as T:
      return value
    case let string as String:
      guard let value = T(string) else { fallthrough }
      return value
    default:
      throw Error.invalidValue
    }
  }
}

    let baseURLString: String = try! AppConfiguration.value(for: "API_BASE_URL")

As you can see I have tried two approaches using Bundle.main.packageInfo and the more verbose method.

Manifest meta-data example (the values coming from Skip.env):

  <meta-data
      android:name="API_BASE_URL"
      android:value="${API_BASE_URL}" />

Can you advise the correct Skip-compatible way to read Android manifest meta-data at runtime? Should we be using a different API than Bundle.main.packageInfo.metaData, or is there specific wiring/config needed in Skip to expose these values?

[marcprux]

The infoDictionary approach only works with a small set of hardwired keys. See Bundle.swift for how we do it.

The more verbose technique for getting the metadata should work, however we don't do any automatic transfer of arbitrary values from Skip.env into the AndroidManifest.xml placeholders. This would be a nice feature for the future, but for right now you would need to manually duplicate the values between the manifest and the Info.plist files.

In general, if you want to share configuration metadata between iOS and Android, we recommend simply doing it yourself with a shared Sources/MyModule/Resources/config.json file and parsing that at runtime with JSONDecoder on the resource Bundle.module.url(forResource: "config.json").