Exception thrown when configuring MicrometerPlugin

Actual behavior (the bug) An exception is thrown when using MicrometerPlugin:

Exception in thread "main" kotlin.KotlinNullPointerException
	at io.javalin.core.JavalinServer.server(JavalinServer.kt:32)
	at io.javalin.plugin.metrics.MicrometerPlugin.apply(MicrometerPlugin.kt:16)
	at io.javalin.core.JavalinConfig.lambda$applyUserConfig$5(JavalinConfig.java:192)
	at java.util.HashMap$Values.forEach(HashMap.java:980)
	at io.javalin.core.JavalinConfig.applyUserConfig(JavalinConfig.java:192)
	at io.javalin.Javalin.create(Javalin.java:85)
	at net.selfdotlearn.javalin.App.main(App.java:10)

Expected behavior No exception, Javalin to start successfully.

To Reproduce

public static void main(String[] args) {
    Javalin app = Javalin.create(config -> {
        config.registerPlugin(new MicrometerPlugin());
    });
    app.get("/", ctx -> ctx.result("Hello World"));
    app.start(8080);
}

See the following for a full example exhibiting the behaviour: https://github.com/jon-ruckwood/javalin-micrometer-example

Additional context Dependencies:

• io.javalin:javalin:3.0.0
• org.slf4j:slf4j-simple:1.7.25
• io.micrometer:micrometer-core:1.1.4

Java version:

java version "1.8.0_112"
Java(TM) SE Runtime Environment (build 1.8.0_112-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.112-b16, mixed mode)

Let me know if you need anything else.

[tipsy]

Sure, I was thinking it should be fixed in server() though:

fun server(): Server {
    config.inner.server = config.inner.server ?: JettyUtil.getOrDefault(config.inner.server)
    return config.inner.server!!
}

[jon-ruckwood]

Thanks guys!