CoinbaseResponse.kt

/**
 * A response from the Coinbase API.
 *
 * In the event that a 2xx is returned [isSuccessful] will be set to true 
 * and [body] will be set.
 * In the event that a non-2xx response is returned [isSuccessful] will be 
 * set to false and [errorBody] will be set.
 * In the event that a request did not result in a response from the monorail 
 * [networkError] will be set.
 */
class CoinbaseResponse<T : Any, U : Any>(
    response: Response<T>?,
    val errorBody: U?,
    val networkError: IOException?
) {
    val body: T? = response?.body()
    val isSuccessful = response?.isSuccessful ?: false
    val code: Int? = response?.code()
}

interface OAuthApi {

    @POST("token")
    fun authToken(@Body body: TokenRequestBody):
            Single<CoinbaseResponse<AccessToken, OAuthError>>
}