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kotlinlang

Hello again, :wave::skin-tone-4:

I was doing a bit of research regarding the best approach to Gracefully Shutdown a Ktor server (Netty Engine - _more specifically_). Looking through the <https://ktor.io/docs/events.html#examples|documentation>, I thought that the recommended way would be through Application Monitoring Events (e.g getting SIGTERM signals). However, during my tests, I noticed that  `onStopping, onPrepareStop and onStopped` ApplicationEvents are not triggered for Netty Engine? Is that expected? If so, do you have any suggestion to properly handle those Graceful Shutdowns?

Thanks once again for your help.

I cannot reproduce your problem:
```val server = embeddedServer(Netty, port = 3333) {
   environment.monitor.subscribe(ApplicationStopping) {
       println("Stopping")
   }

    environment.monitor.subscribe(ApplicationStopped) {
        println("Stopped")
    }

    environment.monitor.subscribe(ApplicationStopPreparing) {
        println("Preparing")
    }
}

server.start(wait = false)
server.stop()```

Did you try terminating the application with `kill -15 PID`? I'm afraid it won't print

This is how I was testing.

```fun main() {
    startKoin { modules(httpClientModule, serviceModule, useCaseModule, redisModule) }
    embeddedServer(Netty, port = 8080, module = Application::module).start(wait = true)
}

fun Application.module() {
    environment.monitor.subscribe(ApplicationStarting) { print("Starting") }
    environment.monitor.subscribe(ApplicationStarted) { print("Started") }
    environment.monitor.subscribe(ApplicationStopping) { print("Stopping") }
    environment.monitor.subscribe(ApplicationStopped)  { print("Stopped") }
    environment.monitor.subscribe(ApplicationStopPreparing)  { print("Preparing") }
}```

image.png

Even the SIGINT signal sent by IntelliJ is not caught.

I believe you will have to add a shutdown hook in which you stop the server
```val server = embeddedServer(Netty, port = 8080) {
  ...
}
Runtime.getRuntime().addShutdownHook(
    thread(start = false) {
        server.stop()
    }
)
server.start(wait = true)```

Or you can use the `addShutdownHook` method:
```server.addShutdownHook {
    server.stop()
}```

Ohhh, I see! This is what I was missing I guess.
Thanks for your help guys. :smiley: