AuthenticationManager.kt

class AuthenticationManager(endpoint: String) {
    var login : LoginResponse? = null

    private val okHttpClient = OkHttpClient.Builder().build()

    private val retrofit = Retrofit.Builder()
        .baseUrl(endpoint)
        .client(okHttpClient)
        .addConverterFactory(GsonConverterFactory.create())
        .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
        .build()

    private val api = retrofit.create(LoginCall::class.java)

    fun authenticateBlocking(): LoginResponse?{
        return api.login(LoginBody(username, password))
            .doOnSuccess { login = it }
            .blockingGet()
    }

    companion object {
        private const val username = "fake_address@gmail.com"
        private const val password = "hrfuqai@8979457"

        const val PROD_ENDPOINT = "https://any_api.com"
    }
}

interface LoginCall {
    @POST("/v2/auth/login")
    fun login(@Body loginBody: LoginBody): Single<LoginResponse>
}