I tried to use Kotlin Coroutine Channels and got an ObsoleteCoroutinesApi warning. Where is the replacement?

Question

I tried to use Kotlin's coroutine channels, but got a warning about the code using an ObsoleteCoroutinesApi. Where is the replacement for the deprecated channels code?

Answer 1

As of today, no replacement yet exists for the Kotlin Coroutine Channels API. Despite confusing naming, they added this annotation to indicate that the existing API is being rewritten and will be replaced.

It's a warning that you can accept. If you have kotlinOptions.allWarningsAsErrors = true stopping you from building your app, you can simply add the @ObsoleteCoroutinesApi annotation to the top of the class to indicate that you accept the risk that your code will require changes.

However, this may quickly spiral out of control as you need to apply these markers to every class that uses these APIs and then every dependency that uses those classes, ad infinitum. To accept these risks project-wide, add the following to your gradle options:

    kotlinOptions.freeCompilerArgs += [
            "-Xuse-experimental=kotlinx.coroutines.ExperimentalCoroutinesApi",
            "-Xuse-experimental=kotlinx.coroutines.ObsoleteCoroutinesApi"]

Feel free to update this answer when a replacement API exists.