SSE (Server Sent Event) - sending data from the server

#sse #coding #programming

Today we will learn about Server-Sent Events (SSE), which can be a good alternative to WebSocket for specific scenarios.

While WebSockets allow for two-way communication between the client and server, they can be complex to implement and configure. In contrast, SSE is simpler and is suitable for services requiring unidirectional communication from the server to the client, such as progress bars, social media feeds, news updates, stock trading, and real-time monitoring.

SSE works by having the client send a request to the server, which then sends messages to the client whenever an event occurs. This one-way communication is maintained through a single HTTP connection, making SSE easier to use in load-balanced environments. If the connection is lost, the client automatically requests a reconnect.

The EventSource object in the browser's JavaScript Web API is used for SSE. It automatically handles reconnections, and the client can close the connection by calling the close() method. SSE is firewall-friendly, as it uses standard HTTP ports and does not require special configurations like WebSocket.

In summary, use SSE for simple, one-way server-to-client communication and WebSocket for essential bidirectional communication. In the next video, we will cover WebRTC, another alternative to WebSocket. See you then.

[xps]

thanks for the clear explanation.

one question. what's stopping SSE-like duplex communication from being implemented in html5? no separate port, unlike web sockets, all on http