Extend LOAD_KEYS_CASE_INSENSITIVELY to support something like snake_case

[yukukotani]

Please think about following example code.

object ExampleSpec : ConfigSpec("") {
    private val exampleKey by required<String>()
    
    fun loadExampleKey(): String {
        val config = Config { addSpec(ExampleSpec) }
        	.enable(Feature.LOAD_KEYS_CASE_INSENSITIVELY)
            .withSource(
            	Source.from.json.file(File("config.json"))
            )
		
        return config[exampleKey]
    }
}

With the code above, We can load:

{
  "exampleKey": "value"
}

But we cannot load with error:
Exception in thread "main" java.util.concurrent.ExecutionException: com.uchuhimo.konf.UnsetValueException: item indentStyle is unset

  "example_key": "value"

It's very nice if both CamelCase and snake_case are supported, especially when we load config from multiple file type such as json and yaml.

[uchuhimo]

@monchi What's your preferred solution? What about adding a pair of functions source.toSnakeCase() and source.toCamelCase() to convert between these two conventions?

P.S. You can explicitly specify the name to workaround it now:

private val exampleKey by required<String>("example_key")

[yukukotani]

@uchuhimo
I want to present users options of using snake case or camel case. So I need example_key and exampleKey to be mapped to config[exampleKey] implicitly.

[uchuhimo]

@monchi I got it. I will consider implementing it in the next release. A pull request is welcome if you are willing to contribute. Since I maintain Konf part-time, there may be some delay before the next release.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed after 30 days if no further activity occurs, but feel free to re-open a closed issue if needed.

[uchuhimo]

@monchi I have released a new version v0.23.0 that implements the desired behavior. You can try it now. Any further feedback is welcome.