Add unit tests for SignalR hub methods

[nickna]

Overview

The SignalR hubs lack unit test coverage. There are 16 hub classes with ~3,744 lines of code and no dedicated unit tests.

Scope

High Priority Hubs

• TaskHub (192 lines) - Task lifecycle management, subscription methods
• SecureHub (220 lines) - Base authentication hub, connection lifecycle
• SpendNotificationHub (355 lines) - Spend threshold alerts

Medium Priority Hubs

• UsageAnalyticsHub (524 lines) - Analytics streaming
• VirtualKeyManagementHub (425 lines) - Key management operations
• HealthMonitoringHub (330 lines) - Health status broadcasts

Lower Priority Hubs

• MetricsHub, WebhookDeliveryHub, SystemNotificationHub
• ImageGenerationHub, VideoGenerationHub, ContentGenerationHub
• AcknowledgmentHub, SecurityMonitoringHub

Test Cases Needed

SecureHub (Base Class)

• OnConnectedAsync adds connection to virtual key group
• OnConnectedAsync aborts connection without valid virtual key
• OnDisconnectedAsync removes from virtual key group
• RequireVirtualKeyId throws HubException when unauthorized
• GetVirtualKeyId extracts ID from context correctly
• CanAccessTaskAsync validates resource ownership

TaskHub

• SubscribeToTask with valid task ID adds to group
• SubscribeToTask with invalid task ID throws HubException
• SubscribeToTask with non-existent task throws "Task not found"
• SubscribeToTask with unauthorized task throws "Unauthorized access"
• UnsubscribeFromTask removes from group
• SubscribeToTaskType adds to type-specific group
• TaskStarted notifies correct groups
• TaskProgress sends progress to task group
• TaskCompleted/TaskFailed/TaskCancelled notify correctly

SpendNotificationHub

• Threshold subscription and notification
• Spend alert broadcasting
• Virtual key group notifications

Implementation Notes

• Create test base class with mock HubCallerContext and Groups
• Use Moq to mock IHubContext, IAsyncTaskService, ISignalRAuthenticationService
• Test both success and error scenarios
• Verify group membership operations

Related Files

• /Services/ConduitLLM.Gateway/Hubs/
• /Tests/ConduitLLM.Tests/Gateway/ (add new Hubs/ directory)

References

• Closes partially: Add comprehensive tests for SignalR hubs and event handlers #218

[nickna]

Implemented in commit e3a95ef. Added 73 unit tests across 5 files for SecureHub (18 tests), TaskHub (26 tests), and SpendNotificationHub (29 tests). All tests pass.