Support empty-dir volumes in Kubernetes, OpenShift, Knative extensions

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

@@ -0,0 +1,15 @@
+
+package io.quarkus.kubernetes.deployment;
+
+import io.dekorate.kubernetes.config.EmptyDirVolume;
+import io.dekorate.kubernetes.config.EmptyDirVolumeBuilder;
+
+public class EmptyDirVolumeConverter {
+
+    public static EmptyDirVolume convert(String volumeName) {
+        EmptyDirVolumeBuilder b = new EmptyDirVolumeBuilder();
+        b.withVolumeName(volumeName);
+        return b.build();
+    }
+
+}

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

@@ -1,5 +1,6 @@
 package io.quarkus.kubernetes.deployment;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -156,6 +157,12 @@ public class KnativeConfig implements PlatformConfiguration {
     @ConfigItem
     Map<String, ConfigMapVolumeConfig> configMapVolumes;
 
+    /**
+     * EmptyDir volumes
+     */
+    @ConfigItem
+    Optional<List<String>> emptyDirVolumes;
+
     /**
      * Git Repository volumes
      */
@@ -315,6 +322,10 @@ public Map<String, ConfigMapVolumeConfig> getConfigMapVolumes() {
         return configMapVolumes;
     }
 
+    public List<String> getEmptyDirVolumes() {
+        return emptyDirVolumes.orElse(Collections.emptyList());
+    }
+
     public Map<String, GitRepoVolumeConfig> getGitRepoVolumes() {
         return gitRepoVolumes;
     }

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

@@ -15,6 +15,7 @@
 import io.dekorate.knative.decorator.AddAzureDiskVolumeToRevisionDecorator;
 import io.dekorate.knative.decorator.AddAzureFileVolumeToRevisionDecorator;
 import io.dekorate.knative.decorator.AddConfigMapVolumeToRevisionDecorator;
+import io.dekorate.knative.decorator.AddEmptyDirVolumeToRevisionDecorator;
 import io.dekorate.knative.decorator.AddHostAliasesToRevisionDecorator;
 import io.dekorate.knative.decorator.AddPvcVolumeToRevisionDecorator;
 import io.dekorate.knative.decorator.AddSecretVolumeToRevisionDecorator;
@@ -333,6 +334,11 @@ private static List<DecoratorBuildItem> createVolumeDecorators(Optional<Project>
                     new AddConfigMapVolumeToRevisionDecorator(ConfigMapVolumeConverter.convert(e))));
         });
 
+        config.getEmptyDirVolumes().forEach(e -> {
+            result.add(new DecoratorBuildItem(KNATIVE,
+                    new AddEmptyDirVolumeToRevisionDecorator(EmptyDirVolumeConverter.convert(e))));
+        });
+
         config.getPvcVolumes().entrySet().forEach(e -> {
             result.add(new DecoratorBuildItem(KNATIVE, new AddPvcVolumeToRevisionDecorator(PvcVolumeConverter.convert(e))));
         });

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

@@ -30,6 +30,7 @@
 import io.dekorate.kubernetes.decorator.AddAzureDiskVolumeDecorator;
 import io.dekorate.kubernetes.decorator.AddAzureFileVolumeDecorator;
 import io.dekorate.kubernetes.decorator.AddConfigMapVolumeDecorator;
+import io.dekorate.kubernetes.decorator.AddEmptyDirVolumeDecorator;
 import io.dekorate.kubernetes.decorator.AddEnvVarDecorator;
 import io.dekorate.kubernetes.decorator.AddHostAliasesDecorator;
 import io.dekorate.kubernetes.decorator.AddImagePullSecretDecorator;
@@ -383,6 +384,10 @@ private static List<DecoratorBuildItem> createMountAndVolumeDecorators(Optional<
             result.add(new DecoratorBuildItem(target, new AddConfigMapVolumeDecorator(ConfigMapVolumeConverter.convert(e))));
         });
 
+        config.getEmptyDirVolumes().forEach(e -> {
+            result.add(new DecoratorBuildItem(target, new AddEmptyDirVolumeDecorator(EmptyDirVolumeConverter.convert(e))));
+        });
+
         config.getPvcVolumes().entrySet().forEach(e -> {
             result.add(new DecoratorBuildItem(target, new AddPvcVolumeDecorator(PvcVolumeConverter.convert(e))));
         });

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

@@ -3,6 +3,7 @@
 import static io.quarkus.kubernetes.deployment.Constants.DEPLOYMENT;
 import static io.quarkus.kubernetes.deployment.Constants.STATEFULSET;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -191,6 +192,12 @@ public enum DeploymentResourceKind {
     @ConfigItem
     Map<String, ConfigMapVolumeConfig> configMapVolumes;
 
+    /**
+     * EmptyDir volumes
+     */
+    @ConfigItem
+    Optional<List<String>> emptyDirVolumes;
+
     /**
      * Git Repository volumes
      */
@@ -453,6 +460,10 @@ public Map<String, ConfigMapVolumeConfig> getConfigMapVolumes() {
         return configMapVolumes;
     }
 
+    public List<String> getEmptyDirVolumes() {
+        return emptyDirVolumes.orElse(Collections.emptyList());
+    }
+
     public Map<String, GitRepoVolumeConfig> getGitRepoVolumes() {
         return gitRepoVolumes;
     }

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

@@ -11,6 +11,7 @@
 import static io.quarkus.kubernetes.deployment.Constants.S2I;
 import static io.quarkus.kubernetes.deployment.Constants.STATEFULSET;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
@@ -220,6 +221,12 @@ public static enum DeploymentResourceKind {
     @ConfigItem
     Map<String, ConfigMapVolumeConfig> configMapVolumes;
 
+    /**
+     * EmptyDir volumes
+     */
+    @ConfigItem
+    Optional<List<String>> emptyDirVolumes;
+
     /**
      * Git Repository volumes
      */
@@ -406,6 +413,10 @@ public Map<String, ConfigMapVolumeConfig> getConfigMapVolumes() {
         return configMapVolumes;
     }
 
+    public List<String> getEmptyDirVolumes() {
+        return emptyDirVolumes.orElse(Collections.emptyList());
+    }
+
     public Map<String, GitRepoVolumeConfig> getGitRepoVolumes() {
         return gitRepoVolumes;
     }

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

@@ -56,6 +56,8 @@ public interface PlatformConfiguration extends EnvVarHolder {
 
     Map<String, ConfigMapVolumeConfig> getConfigMapVolumes();
 
+    List<String> getEmptyDirVolumes();
+
     Map<String, GitRepoVolumeConfig> getGitRepoVolumes();
 
     Map<String, PvcVolumeConfig> getPvcVolumes();

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

@@ -0,0 +1,66 @@
+
+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 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.builder.Version;
+import io.quarkus.maven.dependency.Dependency;
+import io.quarkus.test.ProdBuildResults;
+import io.quarkus.test.ProdModeTestResults;
+import io.quarkus.test.QuarkusProdModeTest;
+
+public class KubernetesWithEmptyDirVolumesTest {
+
+    private static final String NAME = "kubernetes-with-emptydir-volumes";
+
+    @RegisterExtension
+    static final QuarkusProdModeTest config = new QuarkusProdModeTest()
+            .withApplicationRoot((jar) -> jar.addClasses(GreetingResource.class))
+            .setApplicationName(NAME)
+            .setApplicationVersion("0.1-SNAPSHOT")
+            .withConfigurationResource(NAME + ".properties")
+            .setLogFileName("k8s.log")
+            .setForcedDependencies(List.of(Dependency.of("io.quarkus", "quarkus-kubernetes", Version.getVersion())));
+
+    @ProdBuildResults
+    private ProdModeTestResults prodModeTestResults;
+
+    @Test
+    public void assertGeneratedResources() throws IOException {
+        final 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(NAME);
+            });
+
+            assertThat(d.getSpec()).satisfies(deploymentSpec -> {
+                assertThat(deploymentSpec.getTemplate()).satisfies(t -> {
+                    assertThat(t.getSpec()).satisfies(podSpec -> {
+                        assertThat(podSpec.getVolumes()).isNotEmpty();
+                        assertThat(podSpec.getVolumes()).anySatisfy(volume -> {
+                            assertThat(volume.getName()).isEqualTo("cache-volume");
+                            assertThat(volume.getEmptyDir()).isNotNull();
+                        });
+                        assertThat(podSpec.getVolumes()).anySatisfy(volume -> {
+                            assertThat(volume.getName()).isEqualTo("app-data");
+                            assertThat(volume.getEmptyDir()).isNotNull();
+                        });
+                    });
+                });
+            });
+        });
+    }
+}

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

@@ -0,0 +1,3 @@
+quarkus.kubernetes.mounts.cache-volume.path=/cache
+quarkus.kubernetes.mounts.app-data.path=/data
+quarkus.kubernetes.empty-dir-volumes=cache-volume,app-data