Sync documentation of main branch

Author: actions-user

_data/versioned/main/index/quarkus.yaml

@@ -236,7 +236,7 @@ types:
   - title: Security vulnerability detection and reporting in Quarkus
     filename: security-vulnerability-detection.adoc
     summary: Most of the Quarkus tags are registered in the US National Vulnerability Database (NVD) in Common Platform Enumeration (CPE) name format.
-    categories: "security, contributing"
+    categories: "contributing, security"
     id: security-vulnerability-detection
     type: concepts
     url: /guides/security-vulnerability-detection
@@ -273,7 +273,7 @@ types:
   - title: Building a Native Executable
     filename: building-native-image.adoc
     summary: Build native executables with GraalVM or Mandrel.
-    categories: "native, getting-started"
+    categories: "getting-started, native"
     type: tutorial
     url: /guides/building-native-image
   - title: Collect metrics using Micrometer
@@ -394,7 +394,7 @@ types:
   - title: AppCDS
     filename: appcds.adoc
     summary: This reference guide explains how to enable AppCDS with Quarkus.
-    categories: "cloud, core"
+    categories: "core, cloud"
     type: guide
     url: /guides/appcds
   - title: Application Data Caching
@@ -528,7 +528,7 @@ types:
   - title: Deploying on OpenShift
     filename: deploying-to-openshift.adoc
     summary: This guide covers how to deploy a native application on OpenShift.
-    categories: "cloud, native"
+    categories: "native, cloud"
     id: deploy-openshift
     type: guide
     url: /guides/deploying-to-openshift
@@ -813,7 +813,7 @@ types:
   - title: Kubernetes extension
     filename: deploying-to-kubernetes.adoc
     summary: This guide covers how to deploy a native application on Kubernetes.
-    categories: "cloud, native"
+    categories: "native, cloud"
     id: deploy-kubernetes
     type: guide
     url: /guides/deploying-to-kubernetes
@@ -1057,7 +1057,7 @@ types:
   - title: SmallRye Fault Tolerance
     filename: smallrye-fault-tolerance.adoc
     summary: This guide demonstrates how your Quarkus application can utilize the SmallRye Fault Tolerance specification through the SmallRye Fault Tolerance extension.
-    categories: "web, observability"
+    categories: "observability, web"
     type: guide
     url: /guides/smallrye-fault-tolerance
   - title: SmallRye GraphQL
@@ -1087,7 +1087,7 @@ types:
   - title: Testing Your Application
     filename: getting-started-testing.adoc
     summary: "This guide covers testing in JVM mode, native mode, and injection of resources into tests"
-    categories: "native, core, tooling"
+    categories: "native, tooling, core"
     id: testing
     type: guide
     url: /guides/getting-started-testing

_versions/main/guides/vertx-reference.adoc

@@ -1008,6 +1008,52 @@ On macOS Sierra and above you can enable the following socket options:
 quarkus.http.so-reuse-port=true
 ----
 
+== Use a Vert.x context-aware scheduler
+
+Some Mutiny operators need to schedule work on an executor thread pool.
+A good example is `.onItem().delayIt().by(Duration.ofMillis(10)` as it needs such an executor to delay emissions.
+
+The default executor is returned by `io.smallrye.mutiny.infrastructure.Infrastructure` and it is already configured and managed by Quarkus.
+
+That being said, there are cases where you need to make sure that an operation is run on a Vert.x (duplicated) context and not just on any random thread.
+
+The `io.smallrye.mutiny.vertx.core.ContextAwareScheduler` interface offers an API to obtain context-aware schedulers.
+Such a scheduler is configured with:
+
+1. a delegate `ScheduledExecutorService` of your choice (hint: you can reuse `Infrastructure.getDefaultWorkerPool()`), and
+2. a context fetching strategy among:
+  - an explicit `Context`, or
+  - calling `Vertx::getOrCreateContext()` either on the current thread or later when the scheduling request happens, or
+  - calling `Vertx::currentContext()`, which fails if the current thread is not a Vert.x thread.
+
+Here is a sample where `ContextAwareScheduler` is used:
+
+[source,java]
+----
+class MyVerticle extends AbstractVerticle {
+
+    @Override
+    public Uni<Void> asyncStart() {
+        vertx.getOrCreateContext().put("foo", "bar");
+
+        var delegate = Infrastructure.getDefaultWorkerPool();
+        var scheduler = ContextAwareScheduler.delegatingTo(delegate)
+            .withCurrentContext();
+
+        return Uni.createFrom().voidItem()
+                .onItem().delayIt().onExecutor(scheduler).by(Duration.ofMillis(10))
+                .onItem().invoke(() -> {
+                    // Prints "bar"
+                    var ctx = vertx.getOrCreateContext();
+                    System.out.println(ctx.get("foo"));
+                });
+    }
+}
+----
+
+In this example a scheduler is created by capturing the context of the Vert.x event-loop that calls `asyncStart()`.
+The `delayIt` operator uses that scheduler, and we can check that the context that we get in `invoke` is a Vert.x duplicated context where the data for key `"foo"` has been propagated.
+
 == Use a Unix domain socket
 
 Listening on a Unix domain socket allows us to dispense with the overhead of TCP