Handle empty response body in delete requests

Author: josiasmontag

CloudConvert.API/RestHelper.cs

@@ -25,6 +25,13 @@ public async Task<T> RequestAsync<T>(HttpRequestMessage request, CancellationTok
       var response = await _httpClient.SendAsync(request, cancellationToken);
       var responseRaw = await response.Content.ReadAsStringAsync(cancellationToken);
 
+      // Handle empty response body (e.g., HTTP 204 No Content)
+      // System.Text.Json throws when trying to deserialize an empty string
+      if (string.IsNullOrWhiteSpace(responseRaw) || response.StatusCode == System.Net.HttpStatusCode.NoContent)
+      {
+        return default(T);
+      }
+
       return JsonSerializer.Deserialize<T>(responseRaw, DefaultJsonSerializerOptions.SerializerOptions);
     }
 

CloudConvert.Test/Extensions/MockExtensions.cs

@@ -25,6 +25,19 @@ public static IReturnsResult<HttpMessageHandler> MockResponse(this Mock<HttpMess
         });
     }
 
+    public static IReturnsResult<HttpMessageHandler> MockNoContentResponse(this Mock<HttpMessageHandler> mock, string endpoint)
+    {
+      return mock.Protected()
+        .Setup<Task<HttpResponseMessage>>("SendAsync",
+          ItExpr.Is<HttpRequestMessage>(message => message.RequestUri.AbsolutePath.EndsWith(endpoint)),
+          ItExpr.IsAny<CancellationToken>())
+        .ReturnsAsync(new HttpResponseMessage
+        {
+          StatusCode = HttpStatusCode.NoContent,
+          Content = new StringContent(string.Empty)
+        });
+    }
+
     public static void VerifyRequest(this Mock<HttpMessageHandler> mock, string endpoint, Times times)
     {
       mock.Protected()

CloudConvert.Test/TestJobs.cs

@@ -1,10 +1,12 @@
 using System;
 using System.IO;
+using System.Net.Http;
 using System.Text.Json;
 using System.Threading.Tasks;
 using CloudConvert.API;
 using CloudConvert.API.Models;
 using CloudConvert.API.Models.JobModels;
+using CloudConvert.Test.Extensions;
 using Moq;
 using NUnit.Framework;
 
@@ -108,5 +110,25 @@ public async Task DeleteJob()
 
       await _cloudConvertAPI.Object.DeleteJobAsync(id);
     }
+
+    [Test]
+    public async Task DeleteJob_WithNoContentResponse_ShouldNotThrow()
+    {
+      // This test verifies that DeleteJobAsync correctly handles HTTP 204 No Content responses
+      // with empty response bodies, which was broken in v1.4.0 when switching from Newtonsoft.Json to System.Text.Json
+      string id = "cd82535b-0614-4b23-bbba-b24ab0e892f7";
+
+      var httpMessageHandlerMock = new Mock<HttpMessageHandler>();
+      httpMessageHandlerMock.MockNoContentResponse($"/jobs/{id}");
+
+      var httpClient = new HttpClient(httpMessageHandlerMock.Object);
+      var restHelper = new RestHelper(httpClient);
+      var cloudConvertApi = new CloudConvertAPI(restHelper, "API_KEY");
+
+      // This should not throw an exception even though the response body is empty
+      await cloudConvertApi.DeleteJobAsync(id);
+
+      httpMessageHandlerMock.VerifyRequest($"/jobs/{id}", Moq.Times.Once());
+    }
   }
 }