Why is StringValuesBuilder marked as @InternalAPI?...

# ktor

[nordiauwu]

Why is StringValuesBuilder marked as @InternalAPI? It's used in Headers#build which is a public API

[Trevor Stone]

Because they don't want you to use the StringValuesBuilder directly externally, they want you to use the HeadersBuilder

[nordiauwu]

HeadersBuilder also counts as @InternalAPI

[Nikolay Kasyanov]

yep, and with Kotlin 1.5.30-M1 I’m getting compilation errors when I use append in HeadersBuilder closure because of that.

[Nikolay Kasyanov]

Is it a compiler regression? 🤔

[Aleksei Tirman [JB]]

@Nikolay Kasyanov I think it's intended behavior. You can add @OptIn(InternalAPI::class) annotation to make an error go away. Btw, InternalAPI annotation will be removed in version 2.0.0.

[nordiauwu]

@Aleksei Tirman [JB] Isn't it a breaking change? Are you sure they can just release it like it's nothing?

[Nikolay Kasyanov]

@Aleksei Tirman [JB] to clarify, are clients not supposed to use Headers.build at all? 🤔

[Nikolay Kasyanov]

most of the HeadersBuilder API surface is now an internal API, if it’s an intended change

[Nikolay Kasyanov]

the only usable thing I could find is the HeadersBuilder.etag extension method

[Nikolay Kasyanov]

(thanks for sharing the escape hatch via @OptIn though)

[Nikolay Kasyanov]

I’d appreciate a blessed way to build Headers instances that don’t rely on internal APIs, if there are any.

[Nikolay Kasyanov]

@Aleksei Tirman [JB]

Btw, InternalAPI  annotation will be removed in version 2.0.0.

Could you share please what the destiny of APIs currently marked with it would be?

[Aleksei Tirman [JB]]

It will stay wihout InternalAPI annotation, e.g. StringValuesBuilder.