6 The HTTP Server - 6.28 Server Events - 《Micronaut v3.0.0 Documentation》

6.28 Server Events

6.28 Server Events

The HTTP server emits a number of Bean Events, defined in the io.micronaut.runtime.server.event package, that you can write listeners for. The following table summarizes these:

Table 1. Server Events
Event	Description
ServerStartupEvent	Emitted when the server completes startup
ServerShutdownEvent	Emitted when the server shuts down
ServiceReadyEvent	Emitted after all ServerStartupEvent listeners have been invoked and exposes the EmbeddedServerInstance
ServiceStoppedEvent	Emitted after all ServerShutdownEvent listeners have been invoked and exposes the EmbeddedServerInstance

Doing significant work within a listener for a ServerStartupEvent will increase startup time.

The following example defines a ApplicationEventListener that listens for ServerStartupEvent:

Listening for Server Startup Events

import io.micronaut.context.event.ApplicationEventListener;
...
@Singleton
public class StartupListener implements ApplicationEventListener<ServerStartupEvent> {
    @Override
    public void onApplicationEvent(ServerStartupEvent event) {
        // logic here
        ...
    }
}

Alternatively, you can also use the @EventListener annotation on a method of any bean that accepts ServerStartupEvent:

Using @EventListener with ServerStartupEvent

import io.micronaut.runtime.event.annotation.EventListener;
import io.micronaut.runtime.server.event.ServerStartupEvent;
import javax.inject.Singleton;
...
@Singleton
public class MyBean {
    @EventListener
    public void onStartup(ServerStartupEvent event) {
        // logic here
        ...
    }
}