Retrofit 2 not sending data when ProGuard is enabled

Question

I try to login my users using Retrofit 2. (Basically a GET to the login URL with a basic header) It works well but once I ProGuard it, the Header Authorization is not sent a

Answer 1

Another simple solution use @keep from support annotation https://developer.android.com/reference/android/support/annotation/Keep.html

@Keep
interface APIService 
{

    @GET("/user/auth")
    fun auth(@Header(Constants.AUTHORIZATION) authorization: String): Call

}