Capture exceptions in DnsCaptureRawClient.

alanedwardes · Feb 4, 2024 · 9a1c669 · 9a1c669
1 parent bc80f15
commit 9a1c669
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Showing 2 changed files with 35 additions and 7 deletions.
diff --git a/misc/Ae.Dns.Console/Startup.cs b/misc/Ae.Dns.Console/Startup.cs
@@ -188,10 +188,20 @@ async Task GroupToTable(IEnumerable<IGrouping<string?, DnsQuery>> groups, params
                     {
                         await context.Response.WriteAsync($"<li>");
                         await context.Response.WriteAsync($"<b>Served by {capture.Request.ServerName} from {capture.Request.SourceEndpoint}</b>");
-                        await context.Response.WriteAsync($"<pre>{capture.Response.Query}</pre>");
-                        await context.Response.WriteAsync($"<pre>Query bytes: {DnsByteExtensions.ToDebugString(capture.Query)}</pre>");
-                        await context.Response.WriteAsync($"<pre>{capture.Response.Answer}</pre>");
-                        await context.Response.WriteAsync($"<pre>Answer bytes: {DnsByteExtensions.ToDebugString(capture.Answer)}</pre>");
+                        await context.Response.WriteAsync($"<pre>{capture.Response?.Query.ToString() ?? "Error processing query"}</pre>");
+                        await context.Response.WriteAsync($"<pre>{DnsByteExtensions.ToDebugString(capture.Query)}</pre>");
+
+                        if (capture.Answer.HasValue)
+                        {
+                            await context.Response.WriteAsync($"<pre>{capture.Response?.Answer}</pre>");
+                            await context.Response.WriteAsync($"<pre>{DnsByteExtensions.ToDebugString(capture.Answer.Value)}</pre>");
+                        }
+
+                        if (capture.Exception != null)
+                        {
+                            await context.Response.WriteAsync($"<pre>{capture.Exception}</pre>");
+                        }
+
                         await context.Response.WriteAsync($"</li>");
 
                     }

diff --git a/src/Ae.Dns.Client/DnsCaptureRawClient.cs b/src/Ae.Dns.Client/DnsCaptureRawClient.cs
@@ -29,11 +29,15 @@ public sealed class Capture
             /// <summary>
             /// The raw answer.
             /// </summary>
-            public ReadOnlyMemory<byte> Answer { get; set; }
+            public ReadOnlyMemory<byte>? Answer { get; set; }
             /// <summary>
             /// The outgoing response.
             /// </summary>
-            public DnsRawClientResponse Response { get; set; }
+            public DnsRawClientResponse? Response { get; set; }
+            /// <summary>
+            /// An exception, if there was one.
+            /// </summary>
+            public Exception Exception { get; set; }
         }
 
         /// <summary>
@@ -77,7 +81,21 @@ public async Task<DnsRawClientResponse> Query(Memory<byte> buffer, DnsRawClientR
             var queryBuffer = new byte[request.QueryLength];
             buffer.Slice(0, request.QueryLength).CopyTo(queryBuffer);
 
-            var response = await _innerClient.Query(buffer, request, token);
+            DnsRawClientResponse response;
+            try
+            {
+                response = await _innerClient.Query(buffer, request, token);
+            }
+            catch (Exception ex)
+            {
+                Captures.Add(new Capture
+                {
+                    Request = request,
+                    Query = queryBuffer,
+                    Exception = ex
+                });
+                throw;
+            }
 
             if (CaptureFilter(request, response))
             {