Add a way to easily call a bean method after camel has started

[davsclaus]

so you dont have to do the timer:foo?repeatCount=1 trick.

Some kind of annotation or convention method name or something. We do have some event listeners we can hook into. But lets consider making this easy for end users writing their camel k in a source file in java / groovy etc.

[lburgazzoli]

Wonder if we should do this through @BindToRegistry like:

@BindToRegistry
OnStart doOnStart() {
    return context -> doSomething(context);
}

so we can use the same thing also for groovy/kotlin

beans {
    bean<OnStart>("doOnStart") {
        doSomething(it)
    }
}

[davsclaus]

Yeah possible. I was also considering something even easier, with just a special method name or something. As otherwise you have to juggle with all that lambda and annotations.

When all you wanted was just to have a method on RouteBuilder that camel-k would call.

public void onStartup() {
  ... here you can do whatever you want.
  .. you can access context
}

public void configure() {
   ... here is the route builder dsl
}

[lburgazzoli]

Maybe having an interface to extend ? I'm more keen to have a proper type to have better support for tooling so i.e. for plain Java you can do something like

class MyRoute extends RouteBuilder implements OnStartup {
    public void onStartup() {
    }
}

This would also allow the runtime to easily detect what to do without having to rely on reflection to access methods so when a route is added, the camel-k runtime can do something like:

if (route instanceof OnStartup) {
    context.addLifecycleStrategy(...);
}

and for scripting

context {
    onStartup {
        ...
        // this would directly add this closure body as handler
        // for the event by invoking context.addLifecycleStrategy(...)
    }
}

[davsclaus]

The RouteBuilder could also have a onStartup method already so you just need to override it. But the interface is also a good way as its a very common pattern

[lburgazzoli]

Or maybe we can just enrich the RouteBuilder DSL to have a onStartup, onShutdown method so you can write something like:

public void configure() {
   onStartup(this::doOnStartup);
}

That would be agnostic of the runtime

[lburgazzoli]

Fixed on came by apache/camel#3850