Example server scheduler for Bevy Engine

server_tick.rs

/// The ScheduleRunnerPlugin in bevy uses sleep. So it's going to sleep for t duration.
/// If my understanding is correct this example should take execution time into consideration when scheduling.

use tokio::time;
use tokio::process::Command;
use std::time::Duration;
use legion::prelude::*;
use tokio::net::TcpListener;

use bevy:: {
    prelude::*,
    type_registry::TypeRegistryPlugin,
    core::CorePlugin,
    transform::TransformPlugin,
    scene::ScenePlugin,
    diagnostic::DiagnosticsPlugin,
    window::WindowPlugin,
    app::{AppExit}
};

pub struct NetRuntime(tokio::runtime::Handle);

pub fn server_runner(mut app: App) {
    let mut app_exit_event_reader = EventReader::<AppExit>::default();

    let mut runtime = tokio::runtime::Runtime::new().unwrap();
    let handle = runtime.handle();

    let mut interval = handle.block_on(async {
        time::interval(time::Duration::from_micros(33_333))
    });

    let netRuntime = NetRuntime(handle.clone());
    app.resources.insert(netRuntime);

    loop {
        if let Some(app_exit_events) = app.resources.get_mut::<Events<AppExit>>() {
            if app_exit_event_reader.latest(&app_exit_events).is_some() {
                break;
            }
        }
        handle.block_on(async {
            interval.tick().await;
        });
        app.update();
    }
}

fn tick_printer(){
    println!("Tick");
}

fn main() {
    App::build()
        .add_plugin(bevy::type_registry::TypeRegistryPlugin::default())
        .add_plugin(bevy::core::CorePlugin::default())
        .set_runner(server_runner)
        .add_system(tick_printer.system())
        .run();
}