This PubSubServer project is an HTTP+WebSockets server that implements an in-memory, realtime PubSub system and utilizes Gorilla project to upgrade the HTTP server connection to the WebSocket protocol etc.
note: As per project requirement subscription topics, high availability, or persistence are not implemented.
The frontend is contained in index.html. It has 2 buttons to Subscribe and Unsubscribe the websocket connection.
The messages are received via the WebSocket /subscribe endpoint and published via
the HTTP POST /publish endpoint. The reason for not publishing messages over the WebSocket is so that you can easily publish a message with curl.
The server portion is main.go and pubsub.go and implements serving the static frontend assets, the /subscribe WebSocket endpoint and the HTTP POST /publish endpoint.
You can see the Connected console message when clicked on Subscribe button and Disconnected console message when clicked on Unsubscribe button or a "Server message" when a publish message is received.
note: As subscription topics are not implemented, published message will be sent to all the subscribers.
Message struct looks like:
type message struct {
Action string `json:"action"`
Message string `json:"message"`
}Allowed actions are:
- Publish to "publish" forex.
{"action":"publish", "message": "Hi server"} - Subscribe to "subscribe".
- Unsubscribe to "unsubscribe".