WeatherExample https://github.com/skimarxall/WeatherExample/blob/master/app/src/main/java/com/here/example/weather/WeatherApi.kt

WeatherApi.kt

package com.here.example.weather

import retrofit2.Call
import retrofit2.http.GET
import retrofit2.http.Query

interface WeatherApi {

    @GET("/weather/1.0/report.json?app_id={YOUR_APP_ID}&app_code={YOUR_APP_CODE}")
    fun getObservations(@Query("product") product: String,
                        @Query("latitude") latitude: Double,
                        @Query("longitude") longitude: Double,
                        @Query("oneobservation") single: Boolean
    ): Call<WeatherObservation>
}