Let's say I want to build dynamic chat app. I want to update users activity status. I can do this with backend requests every x seconds.

But for example Discord can do this without any requests (nothing in network tab in Chrome).

How can I do this? Thanks!

CodePudding user response：

For this type of requests it's the server who sends the response to the client without requesting in a stream not the usual HTTP requests where the client request something and the server sends the response so it's either you use SSE (server-sent-event) unidirectional tunnel or you use a socket which is bidirectional tunnel (socket.io for example) but for this need sse are better so you don't need to check every x seconds the server notifies the clients subscribed to this tunnel it's like a notification

check these links: server-sent-event-1 server-sent-event-2