scala - how can I inject a keep-alive into a websocket handler in akka-http? -

i've written code communicate browser on websockets using akka-http 10.0.9. works nicely, except connection times out. although we're sending constant stream of data client, client isn't requesting long periods of time.

i know solution inject keep-alive messages incoming websocket source, this:

val s = source(list(data....)).keepalive(15.seconds, () => strict.textmessage("heart beat")) 

however, akka-http api calls flow handle connection:

path("query") {         parameter('session, 'package) {           (session,packageid) =>             val sg = getgraphmanager(session)             sg match {               case left(error) => complete(statuscodes.badrequest -> tserror(msg=error))               case right(gm) =>                 val tsflow = new tsflow(ksource, session)                 handlewebsocketmessages(flow.fromgraph(tsflow.flowgraph))              }          }  } 

consequently, never see incoming source, there's no opportunity inject keep-alive. how should restructure things can inject keep-alive?

the way control how connections dropped server-side change idle-timeout (see docs here , here).

you can set

idle-timeout = infinite 

to disable timeout.

if want use keep alive messages, need sent client side. .keepalive combinator easiest way them if client based on akka streams.