public void TestReadEmptyResponse()
        {
            var twilioRestClient = Substitute.For <ITwilioRestClient>();

            twilioRestClient.AccountSid.Returns("ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
            twilioRestClient.Request(Arg.Any <Request>())
            .Returns(new Response(
                         System.Net.HttpStatusCode.OK,
                         "{\"variables\": [],\"meta\": {\"first_page_url\": \"https://serverless.twilio.com/v1/Services/ZS00000000000000000000000000000000/Environments/ZE00000000000000000000000000000000/Variables?PageSize=50&Page=0\",\"key\": \"variables\",\"next_page_url\": null,\"page\": 0,\"page_size\": 50,\"previous_page_url\": null,\"url\": \"https://serverless.twilio.com/v1/Services/ZS00000000000000000000000000000000/Environments/ZE00000000000000000000000000000000/Variables?PageSize=50&Page=0\"}}"
                         ));

            var response = VariableResource.Read("ZSXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX", "ZEXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX", client: twilioRestClient);

            Assert.NotNull(response);
        }
        public void TestReadRequest()
        {
            var twilioRestClient = Substitute.For <ITwilioRestClient>();
            var request          = new Request(
                HttpMethod.Get,
                Twilio.Rest.Domain.Serverless,
                "/v1/Services/ZSXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/Environments/ZEXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/Variables",
                ""
                );

            twilioRestClient.Request(request).Throws(new ApiException("Server Error, no content"));

            try
            {
                VariableResource.Read("ZSXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX", "ZEXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX", client: twilioRestClient);
                Assert.Fail("Expected TwilioException to be thrown for 500");
            }
            catch (ApiException) {}
            twilioRestClient.Received().Request(request);
        }