Improve error handling and add new test case

Enhanced error handling in TlsClient.Core with a try-catch block and default response creation for exceptions. Refined response handling in TlsClient.HttpClient by replacing status checks with `IsSuccessStatus` and adding null/empty validations.

Added a new test case `ShouldErrorWithCatch` in TlsClient.Issues to validate error handling for 500 Internal Server Error responses. Updated base URL and request path in Issue4.cs to use `https://httpbin.org` and simulate error scenarios.

General improvements include additional null/empty checks and increased test coverage.

Author: ErenKrt

src/TlsClient.Core/TlsClient.cs

@@ -67,11 +67,26 @@ public async Task<Response> RequestAsync(Request request, CancellationToken canc
                     request.Headers.Add(header.Key, header.Value[0]);
                 }
             }
-            var rawResponse= await _wrapper.RequestAsync(RequestHelpers.Prepare(request), cancellationToken);
-            var response = JsonConvert.DeserializeObject<Response>(rawResponse) ?? throw new Exception("Response is null, can't convert object from json.");
-            
-            // Need to free memory, because the native library allocates memory for the response
-            await _wrapper.FreeMemoryAsync(response.Id, cancellationToken);
+
+            Response response;
+
+            try
+            {
+                var rawResponse = await _wrapper.RequestAsync(RequestHelpers.Prepare(request), cancellationToken);
+                response = JsonConvert.DeserializeObject<Response>(rawResponse) ?? throw new Exception("Response is null, can't convert object from json.");
+            }
+            catch(Exception err)
+            {
+                response = new Response()
+                {
+                    Body = err.Message,
+                    Status = 0,
+                };
+            }
+
+            if(!string.IsNullOrEmpty(response.Id))
+                await _wrapper.FreeMemoryAsync(response.Id, cancellationToken);
+
             return response;
         }
 

src/TlsClient.HttpClient/TlsClientHandler.cs

@@ -76,11 +76,14 @@ protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage
                 RequestMessage = request,
             };
 
-            if (!string.IsNullOrWhiteSpace(response.Body) && response.Status!=0)
+            if (!string.IsNullOrWhiteSpace(response.Body) && response.IsSuccessStatus)
             {
                 var parsed = response.Body.ToParsedBase64();
-                httpResponseMessage.Content = new ByteArrayContent(Convert.FromBase64String(parsed.Item2));
-                httpResponseMessage.Content.Headers.ContentType = new MediaTypeHeaderValue(parsed.Item1);
+                if(!string.IsNullOrEmpty(parsed.Item1) && !string.IsNullOrEmpty(parsed.Item2))
+                {
+                    httpResponseMessage.Content = new ByteArrayContent(Convert.FromBase64String(parsed.Item2));
+                    httpResponseMessage.Content.Headers.ContentType = new MediaTypeHeaderValue(parsed.Item1);
+                }
             }
             else
             {

tests/TlsClient.Issues/Issue4.cs

@@ -10,6 +10,29 @@ namespace TlsClient.Issues
 {
     public class Issue4
     {
+        [Fact]
+        public async Task ShouldErrorWithCatch()
+        {
+            using var tlsClient = new TlsClientBuilder()
+                          .WithIdentifier(TlsClientIdentifier.Chrome132)
+                          .WithUserAgent("TestClient 1.0")
+                          .WithFollowRedirects(true)
+                          .WithLibraryPath("D:\\Tools\\TlsClient\\tls-client-windows-64-1.9.1.dll")
+                          .WithTimeout(TimeSpan.FromSeconds(10))
+                          .Build();
+
+
+            var restClient = new TlsRestClientBuilder()
+                .WithBaseUrl("https://httpbin.org")
+                .WithTlsClient(tlsClient)
+                .Build();
+
+            var restReq = new RestRequest("/status/500", Method.Get);
+            var restResponse = await restClient.ExecuteAsync(restReq);
+
+            restResponse.StatusCode.Should().Be(HttpStatusCode.InternalServerError);
+        }
+
         [Fact]
         public async Task ShouldMemoryLeakRestSharp_MultiThreaded()
         {
@@ -34,13 +57,13 @@ public async Task ShouldMemoryLeakRestSharp_MultiThreaded()
 
 
                         var restClient = new TlsRestClientBuilder()
-                            .WithBaseUrl("http://example.com")
+                            .WithBaseUrl("https://httpbin.org")
                             .WithTlsClient(tlsClient)
                             .Build();
 
                         for (int j = 0; j < requestsPerThread; j++)
                         {
-                            var restReq = new RestRequest("/", Method.Get);
+                            var restReq = new RestRequest("/status/500", Method.Get);
                             var restResponse = await restClient.ExecuteAsync(restReq);
                             Console.WriteLine(restResponse.Content);
                         }