Background

Currently, we have two separate adapter services:

• HTTP Adapter: Responsible for posting messages.
• WebSocket Adapter: Responsible for subscribing to messages via WebSocket.

Since WebSocket is a protocol upgrade over HTTP, it is technically feasible to support both HTTP and WebSocket in a single service. This would simplify the architecture and reduce deployment overhead.

Goal

Merge WebSocket functionality into the existing HTTP adapter, allowing it to handle both:

• HTTP POST requests for publishing messages (existing functionality)
• WebSocket connections for subscribing to messages

Approach

We can achieve this by reusing the WebSocket handling logic from the existing WebSocket adapter and integrating it into the HTTP adapter service.

• Copy WebSocket-related code from the WebSocket adapter to the HTTP adapter.
• Add support for HTTP Upgrade requests (Connection: Upgrade and Upgrade: websocket) in the HTTP adapter.
• Ensure WebSocket clients can subscribe to topics just as they do with the standalone WebSocket adapter.

Benefits

• Reduced number of deployed services
• Simplified configuration and maintenance
• Unified endpoint for both publishing and subscribing