tags : HTTP, Web Development, WebSockets, WebRTC
FAQ
What are related technologies
- AJAX + XMLHTTPRequest (Also can use JSON) : no longer popularly used
- FetchAPI
- WebSockets
Server-Sent Events (SSE)
- Introduced 2004
- SSEs are sent via the normal HTTP protocol
- MIME type for SSE is
text/event-stream - Server Push implementation enabling a client to receive automatic updates from a server via an HTTP connection
- Usage
- Send message updates/data streams to a browser client
- Client uses JavaScript API EventSource, to recieve the event stream
- Can run outside of browser context too
Extra details
- HTTP/1.1: 6 SSE connections per browser per domain limit
- HTTP/2: 100 SSE connections per browser per domain limit
- NOT a direct replacement for WebSockets
- SSE does not support messages back from the client to the server.
- You can however do full duplex w SSE(S->C) and RESTAPI(C->S), but that’s a hack.
- Usually SSE easier to setup than Websockets