Devtools does not log outgoing messages for C#

[heyitsaamir]

Incoming messages show up, but not outgoing.

[rajan-chari]

Investigation and Proposed Fix

I have investigated this issue and identified the root cause.

Root Cause Analysis

The event routing logic in AppEvents.cs uses .Equals() to determine which plugins should be skipped when broadcasting events such as ActivitySentEvent. The intention is to prevent a plugin from being notified of its own actions. However, the current equality comparison appears to be incorrectly identifying DevToolsPlugin as equal to the sender plugin, causing it to be skipped when it should receive notifications.

Proposed Solution

Replace .Equals() with ReferenceEquals() in the event handler methods. This provides explicit instance equality checking, ensuring only the actual sender plugin instance is skipped, while observer plugins like DevToolsPlugin continue to receive event notifications.

Implementation

The proposed changes affect three event handlers in Libraries/Microsoft.Teams.Apps/AppEvents.cs:

• OnErrorEvent
• OnActivitySentEvent
• OnActivityResponseEvent

Additional debug logging has been added to facilitate future diagnostics.

Testing

All existing tests (559 total) pass successfully with these changes, and the build completes without errors.

Pull Request

A pull request implementing this fix has been submitted: #262

The PR includes detailed technical analysis and is available for review.