Server Sent Events

If you are looking for realtime features in WEB applciations you often end with Websockets.

Just to be complete I also mention ‘Long/Short polling’ as a client-side pull option. I regard it as mere workaround to a realtime communication implementation.

As always, requirements are key:

• If you need bi-directional realtime features with high volume and low latency, Websocket is your choice.
• If you need to deliver realtime information to many clients, but you can live with the HTTP Request/Response model to trigger actions, Server Sent Events (SSE) are a powerful contender.

SSE is a mechanism that allows the server to asynchronously push the data to the client once the client-server connection is established. The client subscribes to the server data via an Event Source.