Document verticle support

Also add a test verifying that verticle instances can be beans.

docs/src/main/asciidoc/vertx.adoc

@@ -498,6 +498,92 @@ Then, create the native executable with:
 ./mvnw package -Pnative
 ----
 
+== Deploying verticles
+
+https://vertx.io/docs/vertx-core/java/#_verticles[Verticles] is "a simple, scalable, actor-like deployment and concurrency model" provided by _Vert.x_.
+This model does not claim to be a strict actor-model implementation, but it does share similarities especially with respect to concurrency, scaling and deployment.
+To use this model, you write and _deploy_ verticles, communicating with each other by sending messages on the event bus.
+
+You can deploy _verticles_ in Quarkus.
+It supports:
+
+* _bare_ verticle - Java classes extending `io.vertx.core.AbstractVerticle`
+* _Mutiny_ verticle - Java classes extending `io.smallrye.mutiny.vertx.core.AbstractVerticle`
+
+To deploy verticles, use the regular Vert.x API:
+
+[source, java]
+====
+@Inject Vertx vertx;
+
+// ...
+vertx.deployVerticle(MyVerticle.class.getName(), ar -> { });
+vertx.deployVerticle(new MyVerticle(), ar -> { });
+====
+
+You can also pass deployment options to configure the verticle as well as set the number of instances.
+
+Verticles are not _beans_ by default.
+However, you can implement them as _ApplicationScoped_ beans and get injection support:
+
+[source, java]
+====
+package io.quarkus.vertx.verticles;
+
+import io.smallrye.mutiny.Uni;
+import io.smallrye.mutiny.vertx.core.AbstractVerticle;
+import org.eclipse.microprofile.config.inject.ConfigProperty;
+
+import javax.enterprise.context.ApplicationScoped;
+
+@ApplicationScoped
+public class MyBeanVerticle extends AbstractVerticle {
+
+    @ConfigProperty(name = "address") String address;
+
+    @Override
+    public Uni<Void> asyncStart() {
+        return vertx.eventBus().consumer(address)
+                .handler(m -> m.replyAndForget("hello"))
+                .completionHandler();
+    }
+}
+====
+
+You don't have to inject the `vertx` instance but instead leverage the instance stored in the protected field of `AbstractVerticle`.
+
+Then, deploy the verticle instance with:
+
+[source, java]
+====
+package io.quarkus.vertx.verticles;
+
+import io.quarkus.runtime.StartupEvent;
+import io.vertx.mutiny.core.Vertx;
+
+import javax.enterprise.context.ApplicationScoped;
+import javax.enterprise.event.Observes;
+
+@ApplicationScoped
+public class VerticleDeployer {
+
+    public void init(@Observes StartupEvent e, Vertx vertx, MyBeanVerticle verticle) {
+         vertx.deployVerticle(verticle).await().indefinitely();
+    }
+}
+====
+
+If you want to deploy every exposed `AbstractVerticle`, you can use:
+
+[source, java]
+====
+public void init(@Observes StartupEvent e, Vertx vertx, Instance<AbstractVerticle> verticles) {
+    for (AbstractVerticle verticle : verticles) {
+        vertx.deployVerticle(verticle).await().indefinitely();
+    }
+}
+====
+
 == Read only deployment environments
 
 In environments with read only file systems you may receive errors of the form:

extensions/vertx/deployment/src/test/java/io/quarkus/vertx/verticles/MyBeanVerticle.java

@@ -0,0 +1,22 @@
+package io.quarkus.vertx.verticles;
+
+import javax.enterprise.context.ApplicationScoped;
+
+import org.eclipse.microprofile.config.inject.ConfigProperty;
+
+import io.smallrye.mutiny.Uni;
+import io.smallrye.mutiny.vertx.core.AbstractVerticle;
+
+@ApplicationScoped
+public class MyBeanVerticle extends AbstractVerticle {
+
+    @ConfigProperty(name = "address")
+    String address;
+
+    @Override
+    public Uni<Void> asyncStart() {
+        return vertx.eventBus().consumer(address)
+                .handler(m -> m.replyAndForget("hello"))
+                .completionHandler();
+    }
+}

extensions/vertx/deployment/src/test/java/io/quarkus/vertx/verticles/VerticleDeployer.java

@@ -0,0 +1,16 @@
+package io.quarkus.vertx.verticles;
+
+import javax.enterprise.context.ApplicationScoped;
+import javax.enterprise.event.Observes;
+
+import io.quarkus.runtime.StartupEvent;
+import io.vertx.mutiny.core.Vertx;
+
+@ApplicationScoped
+public class VerticleDeployer {
+
+    void deploy(@Observes StartupEvent event, Vertx vertx, MyBeanVerticle verticle) {
+        vertx.deployVerticle(verticle).await().indefinitely();
+    }
+
+}

extensions/vertx/deployment/src/test/java/io/quarkus/vertx/verticles/VerticleDeploymentTest.java

@@ -0,0 +1,36 @@
+package io.quarkus.vertx.verticles;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import javax.inject.Inject;
+
+import org.jboss.shrinkwrap.api.ShrinkWrap;
+import org.jboss.shrinkwrap.api.asset.StringAsset;
+import org.jboss.shrinkwrap.api.spec.JavaArchive;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.quarkus.test.QuarkusUnitTest;
+import io.vertx.mutiny.core.Vertx;
+import io.vertx.mutiny.core.eventbus.Message;
+
+public class VerticleDeploymentTest {
+
+    @RegisterExtension
+    static final QuarkusUnitTest config = new QuarkusUnitTest()
+            .setArchiveProducer(() -> ShrinkWrap
+                    .create(JavaArchive.class)
+                    .addClasses(MyBeanVerticle.class, VerticleDeployer.class)
+                    .addAsResource(new StringAsset("address=foo"), "application.properties"));
+
+    @Inject
+    Vertx vertx;
+
+    @Test
+    public void test() {
+        String s = vertx.eventBus().<String> request("foo", "anyone?")
+                .onItem().apply(Message::body)
+                .await().indefinitely();
+        assertThat(s).isEqualTo("hello");
+    }
+}