in ktor websockets am I expected to manage which client I am kotlinlang #ktor

I store a list of clients that I am connected to, so if there is an update pushed from somewhere else it dispatches it to those clients that are allowed to receive such information

Fábio Carneiro

03/25/2021, 3:26 PM

@Joost Klitsie so that means the answer to my question is no? how does it know which client to send the message if I call

send()

? Is it broadcast then?

I'm opening two different connections and they dont receive all the messages

Joost Klitsie

03/25/2021, 3:28 PM

well if you have an incoming session it gives you a session

so that only counts for that session

if you want to send things to that session, you'd have to be able to reference it

by for example storing it into a list

and then iterate over all your sessions

and send out the socket events

Fábio Carneiro

03/25/2021, 3:39 PM

right, but I am already in the session context

I have some objects in a higher scope, that are manipulated in the session scope

I wasnted to confirm this session was between 1:1 client and server

because the examples have this

for (frame in incoming) {

and for me its odd how this gets executed

ah ok I think I got it.

incoming

is a receivechannel and what I am basically doing is configuring a callback for every frame I receive

Joost Klitsie

03/25/2021, 4:01 PM

I guess you wanna do something like:

Copy code

webSocket("websocket/path") {
    addActiveSession(this) // whatever you want, just store the session
    incoming.receiveAsFlow().collect { frame ->
        // Handle incoming stuff, or just wait until this is cancelled (aka session ended)
    }
    removeFromActiveSessions(this)
}

then if you want to send a message to all your sessions, check where you stored the sessions and on each you can simply call:

Copy code

sessions.forEach { session ->
    if (session.isActive) {
        connection.outgoing.send(Frame.Binary(true, bytes)) // bytes is in my case a json object converted to byte array
     } else {
         removeFromActiveSessions(session)
     }
}

Fábio Carneiro

03/25/2021, 5:17 PM

yes, I am already using flow for the output

but the question was the input

that helps a lot

10 Views