Handle gateway deletion when active WebSocket connections exist

Description

Determine and implement the appropriate behavior when deleting a gateway that has active WebSocket connections to the control plane. The system must handle these active connections gracefully, with two possible approaches to be decided.

Decision Required

Option 1: Block Deletion

• Prevent deletion when active connections exist
• Return HTTP 409 Conflict with connection count
• Require connections to be closed before deletion

Option 2: Allow Deletion with Immediate Cleanup

• Allow deletion even with active connections
• Immediately drop all active WebSocket connections
• Ensure connections are properly closed/terminated
• Return HTTP 204 No Content after successful deletion and cleanup

Acceptance Criteria

Once approach is decided, implement the following:

• Determine and document which approach to use (blocking vs. cleanup)
• Implement chosen approach consistently
• Active WebSocket connections are handled appropriately (blocked or dropped)
• If connections are dropped, they are closed immediately and cleanly
• Appropriate HTTP response returned (409 if blocked, 204 if allowed with cleanup)
• Gateway instances are notified of deletion (if cleanup approach chosen)

Testing

Test Case 1: Gateway with active connections

1. Create a gateway
2. Establish one or more WebSocket connections from gateway to control plane
3. Attempt to delete the gateway
4. Verify behavior based on chosen approach:
   • If blocking: HTTP 409 Conflict response with connection count
   • If cleanup: HTTP 204 No Content, verify connections immediately dropped

Test Case 2: Gateway without active connections

1. Create a gateway with no active connections (or close all connections)
2. Attempt to delete the gateway
3. Verify: HTTP 204 No Content (successful deletion)

Considerations

• Connection lifecycle: How should gateway instances be notified if connections are dropped?
• Graceful shutdown: Should there be a grace period or immediate termination?
• Reconnection behavior: Dropped connections should not attempt to reconnect after deletion
• Consistency: Behavior should align with overall system design and user expectations

Related

• Related to: Issue #68 (API deployment validation)

Version

Platform API v1

Start by tracing the gateway deletion endpoint and active WebSocket connection lifecycle; the issue names no files or tests. Decide between blocking and cleanup, then add coverage for both connection states and verify the selected HTTP response and notification behavior.