feat: capture and display request and response headers

Adds request and response headers support to DebugProbe.

Author: georgidhristov

DebugProbe.AspNetCore.Tests/Rendering/HtmlRendererTests.cs

@@ -64,7 +64,7 @@ public void Html_encoding_escapes_untrusted_values()
         var entry = CreateEntry();
         entry.Method = "<script>alert(1)</script>";
         entry.Path = "/orders/<bad>";
-        entry.Headers["X-Unsafe"] = "<img src=x onerror=alert(1)>";
+        entry.RequestHeaders["X-Unsafe"] = "<img src=x onerror=alert(1)>";
 
         var html = HtmlRenderer.RenderDetailsPage(
             entry,
@@ -94,7 +94,15 @@ private static DebugEntry CreateEntry()
             DurationMs = 12,
             Timestamp = new DateTimeOffset(2026, 1, 2, 3, 4, 5, TimeSpan.Zero),
             RequestTimeUtc = new DateTimeOffset(2026, 1, 2, 3, 4, 5, TimeSpan.Zero),
-            Headers = new Dictionary<string, string> { ["X-Test"] = "yes" }
+            RequestHeaders = new Dictionary<string, string>
+            {
+                ["X-Test"] = "yes"
+            },
+
+            ResponseHeaders = new Dictionary<string, string>
+            {
+                ["Content-Type"] = "application/json"
+            }
         };
     }
 

DebugProbe.AspNetCore/Assets/html/details.html

@@ -90,6 +90,7 @@ <h2>{{method}} {{path}}</h2>
         </div>
     </div>
 
+
     <div class="section-title">
         <h3>Request URL</h3>
 
@@ -104,6 +105,20 @@ <h3>Request URL</h3>
         <pre>{{requestUrl}}</pre>
     </div>
 
+    <div class="section-title">
+        <h3>Request Headers</h3>
+
+        <div class="code-badges">
+            <span class="code-badge payload-text">
+                HEADERS
+            </span>
+        </div>
+    </div>
+
+    <div class="code-block">
+        <button class="copy-btn" onclick="copyText(this)">Copy</button>
+        <pre>{{requestHeaders}}</pre>
+    </div>
 
     <div class="section-title">
         <h3>Request Body</h3>
@@ -119,6 +134,20 @@ <h3>Request Body</h3>
         <pre>{{request}}</pre>
     </div>
 
+    <div class="section-title">
+        <h3>Response Headers</h3>
+
+        <div class="code-badges">
+            <span class="code-badge payload-text">
+                HEADERS
+            </span>
+        </div>
+    </div>
+
+    <div class="code-block">
+        <button class="copy-btn" onclick="copyText(this)">Copy</button>
+        <pre>{{responseHeaders}}</pre>
+    </div>
 
     <div class="section-title">
         <h3>Response Body</h3>

DebugProbe.AspNetCore/DebugProbe.AspNetCore.csproj

@@ -41,11 +41,11 @@
 	</ItemGroup>
 
 	<ItemGroup>
-		<EmbeddedResource Include="Assets\**\*.html" />
-		<EmbeddedResource Include="Assets\**\*.css" />
-		<EmbeddedResource Include="Assets\**\*.js" />
-		<EmbeddedResource Include="Assets\**\*.png" />
-		<EmbeddedResource Include="Assets\**\*.ico" />
+		<EmbeddedResource Include="Assets\**\*" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<None Remove="Assets\**\*" />
 	</ItemGroup>
 
 	<ItemGroup>

DebugProbe.AspNetCore/Internal/Rendering/HtmlRenderer.cs

@@ -43,8 +43,11 @@ public static string RenderIndexPage(List<DebugEntry> items)
 
     public static string RenderDetailsPage(DebugEntry x, DebugEnvironment e, string req, string res)
     {
-        var headers = string.Join("", x.Headers.Select(h =>
-            $"<tr><td>{Encode(h.Key)}</td><td>{Encode(h.Value)}</td></tr>"));
+        //var headers = string.Join("", x.Reqe.Select(h =>
+        //    $"<tr><td>{Encode(h.Key)}</td><td>{Encode(h.Value)}</td></tr>"));
+
+        var requestHeaders = string.Join(Environment.NewLine, x.RequestHeaders.Select(h => $"{h.Key}: {h.Value}"));
+        var responseHeaders = string.Join(Environment.NewLine, x.ResponseHeaders.Select(h => $"{h.Key}: {h.Value}"));
 
         var pathWithQuery = string.IsNullOrEmpty(x.Query)
             ? x.Path
@@ -79,13 +82,15 @@ public static string RenderDetailsPage(DebugEntry x, DebugEnvironment e, string
             .Replace("{{requestUrl}}", Encode(string.IsNullOrEmpty(x.RequestUrl) ? "" : x.RequestUrl))
             .Replace("{{requestType}}", GetPayloadType(req))
             .Replace("{{requestTypeClass}}", GetPayloadTypeClass(req))
+            .Replace("{{requestHeaders}}", Encode(requestHeaders))
             .Replace("{{request}}", Encode(string.IsNullOrEmpty(req) ? "" : req))
 
             .Replace("{{responseType}}", GetPayloadType(res))
             .Replace("{{responseTypeClass}}", GetPayloadTypeClass(res))
-            .Replace("{{response}}", Encode(string.IsNullOrEmpty(res) ? "" : res))
+            .Replace("{{responseHeaders}}", Encode(responseHeaders))
+            .Replace("{{response}}", Encode(string.IsNullOrEmpty(res) ? "" : res));
 
-            .Replace("{{headers}}", headers);
+            //.Replace("{{headers}}", headers);
 
         return BuildLayout(content);
     }

DebugProbe.AspNetCore/Middleware/DebugProbeMiddleware.cs

@@ -95,6 +95,11 @@ public async Task Invoke(HttpContext context, DebugEntryStore store)
                 RequestSize = context.Request.ContentLength ?? Encoding.UTF8.GetByteCount(requestBody),
                 ResponseSize = Encoding.UTF8.GetByteCount(responseBody),
 
+
+                // Request Headers
+                RequestHeaders = context.Request.Headers.ToDictionary(x => x.Key, x => 
+                SensitiveHeaders.Contains(x.Key) ? "[REDACTED]" : x.Value.ToString()),
+
                 // Request
                 RequestUrl = $"{context.Request.Scheme}://{context.Request.Host}" + 
                         $"{context.Request.Path}{context.Request.QueryString}",
@@ -103,10 +108,9 @@ public async Task Invoke(HttpContext context, DebugEntryStore store)
                 // Response
                 ResponseBody = Trim(responseBody, maxBodySize),
 
-                // Headers
-                Headers = context.Request.Headers.ToDictionary(
-                    x => x.Key,
-                    x => SensitiveHeaders.Contains(x.Key) ? "[REDACTED]" : x.Value.ToString()),
+                // Response Headers
+                ResponseHeaders = context.Response.Headers.ToDictionary(x => x.Key, x => 
+                SensitiveHeaders.Contains(x.Key)? "[REDACTED]" : x.Value.ToString()),
 
                 // Other
                 Timestamp = DateTime.UtcNow,

DebugProbe.AspNetCore/Models/DebugEntry.cs

@@ -20,7 +20,8 @@ public class DebugEntry
     public string ResponseBody { get; set; } = default!;
 
     // Headers
-    public Dictionary<string, string> Headers { get; set; } = new();
+    public Dictionary<string, string> RequestHeaders { get; set; } = new();
+    public Dictionary<string, string> ResponseHeaders { get; set; } = new();
 
     // Metadata
     public DateTimeOffset Timestamp { get; set; }