Add nodeSelector capability to kubernetes extension

docs/src/main/asciidoc/deploying-to-kubernetes.adoc

@@ -716,6 +716,27 @@ spec:
         ip: 10.0.0.0
 ----
 
+=== Add nodeSelector
+To add a nodeSelector in the generated `Deployment` (more information can be found in https://kubernetes.io/docs/tasks/configure-pod-container/assign-pods-nodes[Kubernetes documentation]), just apply the following configuration:
+
+[source,properties]
+----
+quarkus.kubernetes.node-selector.key=diskType
+quarkus.kubernetes.node-selector.value=ssd
+----
+
+This would generate the following `nodeSelector` section in the `deployment` definition:
+
+[source,yaml]
+----
+kind: Deployment
+spec:
+  template:
+    spec:
+      nodeSelector:
+        diskType: ssd
+----
+
 === Container Resources Management
 
 CPU & Memory limits and requests can be applied to a `Container` (more info in https://kubernetes.io/docs/concepts/configuration/manage-resources-containers/[Kubernetes documentation]) using the following configuration:

extensions/kubernetes/vanilla/deployment/src/main/java/io/quarkus/kubernetes/deployment/AddNodeSelectorDecorator.java

@@ -0,0 +1,24 @@
+package io.quarkus.kubernetes.deployment;
+
+import io.dekorate.kubernetes.decorator.NamedResourceDecorator;
+import io.dekorate.utils.Strings;
+import io.fabric8.kubernetes.api.model.ObjectMeta;
+import io.fabric8.kubernetes.api.model.PodSpecFluent;
+
+public class AddNodeSelectorDecorator extends NamedResourceDecorator<PodSpecFluent<?>> {
+    private final String nodeSelectorKey;
+    private final String nodeSelectorValue;
+
+    public AddNodeSelectorDecorator(String deploymentName, String nodeSelectorKey, String nodeSelectorValue) {
+        super(deploymentName);
+        this.nodeSelectorKey = nodeSelectorKey;
+        this.nodeSelectorValue = nodeSelectorValue;
+    }
+
+    public void andThenVisit(PodSpecFluent<?> podSpec, ObjectMeta resourceMeta) {
+        if (Strings.isNotNullOrEmpty(nodeSelectorKey) && Strings.isNotNullOrEmpty(nodeSelectorValue)) {
+            podSpec.removeFromNodeSelector(nodeSelectorKey);
+            podSpec.addToNodeSelector(nodeSelectorKey, nodeSelectorValue);
+        }
+    }
+}

extensions/kubernetes/vanilla/deployment/src/main/java/io/quarkus/kubernetes/deployment/KnativeProcessor.java

@@ -290,6 +290,8 @@ public List<DecoratorBuildItem> createDecorators(ApplicationInfoBuildItem applic
         result.addAll(createAppConfigVolumeAndEnvDecorators(name, config));
         config.hostAliases().entrySet().forEach(e -> result.add(new DecoratorBuildItem(KNATIVE,
                 new AddHostAliasesToRevisionDecorator(name, HostAliasConverter.convert(e)))));
+        config.nodeSelector().ifPresent(n -> result.add(new DecoratorBuildItem(KNATIVE,
+                new AddNodeSelectorDecorator(name, n.key(), n.value()))));
         config.sidecars().entrySet().forEach(e -> result
                 .add(new DecoratorBuildItem(KNATIVE, new AddSidecarToRevisionDecorator(name, ContainerConverter.convert(e)))));
 

extensions/kubernetes/vanilla/deployment/src/main/java/io/quarkus/kubernetes/deployment/KubernetesCommonHelper.java

@@ -852,6 +852,10 @@ private static List<DecoratorBuildItem> createPodDecorators(String target, Strin
         config.hostAliases().entrySet().forEach(e -> result
                 .add(new DecoratorBuildItem(target, new AddHostAliasesDecorator(name, HostAliasConverter.convert(e)))));
 
+        config.nodeSelector()
+                .ifPresent(n -> result.add(
+                        new DecoratorBuildItem(target, new AddNodeSelectorDecorator(name, n.key(), n.value()))));
+
         config.initContainers().entrySet().forEach(e -> result
                 .add(new DecoratorBuildItem(target, new AddInitContainerDecorator(name, ContainerConverter.convert(e)))));
 

extensions/kubernetes/vanilla/deployment/src/main/java/io/quarkus/kubernetes/deployment/NodeSelectorConfig.java

@@ -0,0 +1,13 @@
+package io.quarkus.kubernetes.deployment;
+
+public interface NodeSelectorConfig {
+    /**
+     * The key of the nodeSelector.
+     */
+    String key();
+
+    /**
+     * The value of the nodeSelector.
+     */
+    String value();
+}

extensions/kubernetes/vanilla/deployment/src/main/java/io/quarkus/kubernetes/deployment/PlatformConfiguration.java

@@ -204,6 +204,11 @@ public interface PlatformConfiguration extends EnvVarHolder {
     @WithName("hostaliases")
     Map<String, HostAliasConfig> hostAliases();
 
+    /**
+     * The nodeSelector.
+     */
+    Optional<NodeSelectorConfig> nodeSelector();
+
     /**
      * Resources requirements.
      */

extensions/kubernetes/vanilla/deployment/src/test/java/io/quarkus/kubernetes/deployment/KubernetesConfigTest.java

@@ -228,6 +228,10 @@ void kubernetes() throws Exception {
         assertEquals("konoha", hostAliases.get("ip"));
         assertIterableEquals(List.of("dev", "qly", "prod"), (Iterable<String>) hostAliases.get("hostnames"));
 
+        Map<String, Object> nodeSelector = deployment().map("spec").map("template").map("spec").asMap("nodeSelector");
+        assertTrue(nodeSelector.containsKey("jutsu"));
+        assertEquals("katon", nodeSelector.get("jutsu"));
+
         Map<String, Object> limits = container().map("resources").asMap("limits");
         assertEquals("fuuton", limits.get("cpu"));
         assertEquals("raiton", limits.get("memory"));

extensions/kubernetes/vanilla/deployment/src/test/resources/application-kubernetes.properties

@@ -132,6 +132,9 @@ quarkus.kubernetes.deployment-target=kubernetes,openshift,knative,minikube
 quarkus.kubernetes.hostaliases.konoha.ip=0.0.0.0
 quarkus.kubernetes.hostaliases.konoha.hostnames=dev,qly,prod
 
+quarkus.kubernetes.node-selector.key=jutsu
+quarkus.kubernetes.node-selector.value=katon
+
 quarkus.kubernetes.resources.limits.cpu=fuuton
 quarkus.kubernetes.resources.limits.memory=raiton
 quarkus.kubernetes.resources.requests.cpu=katon

integration-tests/kubernetes/quarkus-standard-way/src/test/java/io/quarkus/it/kubernetes/KubernetesWithNodeSelectorTest.java

@@ -0,0 +1,55 @@
+package io.quarkus.it.kubernetes;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.fabric8.kubernetes.api.model.HasMetadata;
+import io.fabric8.kubernetes.api.model.apps.Deployment;
+import io.quarkus.test.ProdBuildResults;
+import io.quarkus.test.ProdModeTestResults;
+import io.quarkus.test.QuarkusProdModeTest;
+
+public class KubernetesWithNodeSelectorTest {
+
+    @RegisterExtension
+    static final QuarkusProdModeTest config = new QuarkusProdModeTest()
+            .withApplicationRoot((jar) -> jar.addClasses(GreetingResource.class))
+            .setApplicationName("nodeselector")
+            .setApplicationVersion("0.1-SNAPSHOT")
+            .withConfigurationResource("kubernetes-with-nodeselector.properties");
+
+    @ProdBuildResults
+    private ProdModeTestResults prodModeTestResults;
+
+    @Test
+    public void assertGeneratedResources() throws IOException {
+        Map<String, String> expectedNodeSelector = Map.of("diskType", "ssd");
+
+        Path kubernetesDir = prodModeTestResults.getBuildDir().resolve("kubernetes");
+        assertThat(kubernetesDir)
+                .isDirectoryContaining(p -> p.getFileName().endsWith("kubernetes.json"))
+                .isDirectoryContaining(p -> p.getFileName().endsWith("kubernetes.yml"));
+        List<HasMetadata> kubernetesList = DeserializationUtil
+                .deserializeAsList(kubernetesDir.resolve("kubernetes.yml"));
+        assertThat(kubernetesList.get(0)).isInstanceOfSatisfying(Deployment.class, d -> {
+            assertThat(d.getMetadata()).satisfies(m -> {
+                assertThat(m.getName()).isEqualTo("nodeselector");
+            });
+
+            assertThat(d.getSpec()).satisfies(deploymentSpec -> {
+                assertThat(deploymentSpec.getTemplate()).satisfies(t -> {
+                    assertThat(t.getSpec()).satisfies(podSpec -> {
+                        assertThat(podSpec.getNodeSelector()).containsExactlyEntriesOf(expectedNodeSelector);
+                    });
+                });
+            });
+        });
+    }
+}

integration-tests/kubernetes/quarkus-standard-way/src/test/resources/kubernetes-with-nodeselector.properties

@@ -0,0 +1,2 @@
+quarkus.kubernetes.node-selector.key=diskType
+quarkus.kubernetes.node-selector.value=ssd