Improve tag handling for client events with custom [Tags]

Previously, the default "{HubName} Events" tag was always added for client events, even when all events had custom [Tags] attributes. Now, only custom tags are added in such cases, and the default tag is used only if no custom tags are present. Added a test and supporting hub/interface to verify that the default tag is omitted when all client events have custom tags.

Author: icnocop

src/SignalR.OpenApi/Generation/SignalROpenApiDocumentGenerator.cs

@@ -449,10 +449,25 @@ private void AddDocumentTags(OpenApiDocument document, IReadOnlyList<SignalRHubI
 
             foreach (var clientEvent in hub.ClientEvents)
             {
-                var eventTag = $"{hub.Name} Events";
-                if (tagSet.Add(eventTag))
+                if (clientEvent.Tags.Count > 0)
                 {
-                    tagNames.Add(eventTag);
+                    // Client event has custom [Tags] — register those tags.
+                    foreach (var tag in clientEvent.Tags)
+                    {
+                        if (tagSet.Add(tag))
+                        {
+                            tagNames.Add(tag);
+                        }
+                    }
+                }
+                else
+                {
+                    // No custom tags — use the default "{HubName} Events" tag.
+                    var eventTag = $"{hub.Name} Events";
+                    if (tagSet.Add(eventTag))
+                    {
+                        tagNames.Add(eventTag);
+                    }
                 }
             }
         }

test/SignalR.OpenApi.Tests/SignalROpenApiDocumentGeneratorTests.cs

@@ -1260,6 +1260,24 @@ public void GenerateDocument_ClientEventWithoutTagsAttribute_UsesDefaultTag()
         CollectionAssert.Contains(tagNames, "TypedChat Events");
     }
 
+    /// <summary>
+    /// Verifies that the default "{HubName} Events" tag is not added to document tags
+    /// when all client events have custom [Tags] attributes.
+    /// </summary>
+    [TestMethod]
+    public void GenerateDocument_AllClientEventsHaveCustomTags_OmitsDefaultEventsTag()
+    {
+        var (discoverer, generator) = CreateServices();
+        var hubs = discoverer.DiscoverHubs();
+        var doc = generator.GenerateDocument(hubs);
+
+        Assert.IsNotNull(doc.Tags);
+        var tagNames = doc.Tags.Select(t => t.Name).ToList();
+
+        CollectionAssert.DoesNotContain(tagNames, "AllTaggedEvents Events");
+        CollectionAssert.Contains(tagNames, "Notifications");
+    }
+
     /// <summary>
     /// Verifies that document tags are deduplicated when multiple methods share the same tag.
     /// </summary>

test/SignalR.OpenApi.Tests/TestHubs/AllTaggedEventsHub.cs

@@ -0,0 +1,20 @@
+// Copyright (c) SignalR.OpenApi Contributors. Licensed under the MIT License.
+
+using Microsoft.AspNetCore.SignalR;
+
+namespace SignalR.OpenApi.Tests.TestHubs;
+
+/// <summary>
+/// A typed hub whose client events all have custom <see cref="Microsoft.AspNetCore.Http.TagsAttribute"/>.
+/// </summary>
+public class AllTaggedEventsHub : Hub<IAllTaggedClient>
+{
+    /// <summary>
+    /// Sends a ping to all clients.
+    /// </summary>
+    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+    public async Task Ping()
+    {
+        await this.Clients.All.UserConnected("system");
+    }
+}

test/SignalR.OpenApi.Tests/TestHubs/IAllTaggedClient.cs

@@ -0,0 +1,28 @@
+// Copyright (c) SignalR.OpenApi Contributors. Licensed under the MIT License.
+
+using Microsoft.AspNetCore.Http;
+
+namespace SignalR.OpenApi.Tests.TestHubs;
+
+/// <summary>
+/// Client interface where all events have custom <see cref="TagsAttribute"/>.
+/// Used to verify the default "{HubName} Events" tag is omitted.
+/// </summary>
+public interface IAllTaggedClient
+{
+    /// <summary>
+    /// Notifies that a user connected.
+    /// </summary>
+    /// <param name="user">The user who connected.</param>
+    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+    [Tags("Notifications")]
+    Task UserConnected(string user);
+
+    /// <summary>
+    /// Notifies that a user disconnected.
+    /// </summary>
+    /// <param name="user">The user who disconnected.</param>
+    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+    [Tags("Notifications")]
+    Task UserDisconnected(string user);
+}