Periodic function execution?

[epsilon-0]

I have a use case where I want to run a function (to clean up things) every X seconds.
Currently, I don't see how to do this with the App.h or Loop.h (maybe I missed some thing?).

Is there any way to periodically run a function here?

Thanks!

[ghost]

A timer?

[epsilon-0]

Are these in uWebSockets? or should I look at usockets for a lower level of access?

[Jacob-Burckhardt]

This calls send every 1000 milliseconds and follows the requirements of the library for thread-safe code:

#include "App.h"
   
using namespace std;

struct PerSocketData {};

uWS::WebSocket<false, true, PerSocketData> *gws=nullptr;
    
int main() {
   auto loop = uWS::Loop::get();

   struct us_timer_t *delayTimer = us_create_timer((struct us_loop_t *) loop, 0, 0);

   us_timer_set(delayTimer, [](struct us_timer_t *) {
                               if (gws) {
                                  cout << "calling send" << endl;
                                  gws->send("from server", uWS::OpCode::TEXT);
                               }
                            }, 1000, 1000);
   
   uWS::App app;

   app.ws<PerSocketData>("/*", {
         .idleTimeout = 0,
         .sendPingsAutomatically = false,
         .open = [](auto *ws) {
                    gws = ws;
                 },
         .close = [](auto */*ws*/, int /*code*/, std::string_view /*message*/) {
                     gws = nullptr;
                  }
      }).listen(9001, [](auto *) {
                      });

   app.run();
}

[epsilon-0]

!!!! This worked nicely, thanks!!

[alexxmanea]

Sorry for waking up this post. Is it possible to pass the "app", instead of "gws", to the timer's callback function? I want to make a global publish, to every socket connected.

[ghost]

Easiest to make the app global

[alexxmanea]

I understood that this should "follow the requirements of the library for thread-safe code", because it runs single threaded, on the same thread as the App. But will this also work fine in a multi-threaded uWS::App?

[ghost]

Make it global but thread local?