Create OpenAPI Kubernetes client integration with OKE

gradle/libs.versions.toml

@@ -23,6 +23,7 @@ managed-apache-http-core5 = "5.3.1"
 micronaut-gradle-plugin = "4.4.4"
 micronaut-groovy = "4.5.0"
 micronaut-kotlin = "4.5.0"
+micronaut-kubernetes = "6.2.1"
 micronaut-micrometer = "5.9.3"
 micronaut-reactor = "3.6.0"
 micronaut-rxjava2 = "2.6.0"
@@ -41,6 +42,7 @@ micronaut-core = { module = 'io.micronaut:micronaut-core-bom', version.ref = 'mi
 # micronaut boms
 micronaut-groovy = { module = "io.micronaut.groovy:micronaut-groovy-bom", version.ref = "micronaut-groovy" }
 micronaut-kotlin = { module = "io.micronaut.kotlin:micronaut-kotlin-bom", version.ref = "micronaut-kotlin" }
+micronaut-kubernetes = { module = "io.micronaut.kubernetes:micronaut-kubernetes-bom", version.ref = "micronaut-kubernetes" }
 micronaut-micrometer = { module = "io.micronaut.micrometer:micronaut-micrometer-bom", version.ref = "micronaut-micrometer" }
 micronaut-reactor = { module = "io.micronaut.reactor:micronaut-reactor-bom", version.ref = "micronaut-reactor" }
 micronaut-rxjava2 = { module = "io.micronaut.rxjava2:micronaut-rxjava2-bom", version.ref = "micronaut-rxjava2" }

oraclecloud-oke-kubernetes-client/build.gradle

@@ -0,0 +1,28 @@
+plugins {
+    id 'io.micronaut.build.internal.oraclecloud-module'
+}
+
+dependencies {
+    api mnKubernetes.micronaut.kubernetes.client.openapi.common
+    implementation mnValidation.validation
+    implementation projects.micronautOraclecloudBmcContainerengine
+
+    testImplementation mnKubernetes.micronaut.kubernetes.client.openapi
+    api projects.micronautOraclecloudCommon
+    testImplementation mn.micronaut.context
+    testAnnotationProcessor mn.micronaut.inject.java
+    testImplementation mn.micronaut.inject.java
+    testImplementation mn.micronaut.inject.groovy
+    testImplementation mn.micronaut.inject.groovy.test
+    testImplementation mn.micronaut.http.server.netty
+}
+
+tasks.withType(Test).configureEach {
+    useJUnitPlatform()
+}
+
+micronautBuild {
+    binaryCompatibility {
+        enabled = false
+    }
+}

oraclecloud-oke-kubernetes-client/src/main/java/io/micronaut/oraclecloud/oke/kubernetes/client/OkeKubeConfigLoader.java

@@ -0,0 +1,113 @@
+/*
+ * Copyright 2017-2024 original authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micronaut.oraclecloud.oke.kubernetes.client;
+
+import com.oracle.bmc.containerengine.ContainerEngineClient;
+import com.oracle.bmc.containerengine.model.CreateClusterKubeconfigContentDetails;
+import com.oracle.bmc.containerengine.model.CreateClusterKubeconfigContentDetails.Endpoint;
+import com.oracle.bmc.containerengine.requests.CreateKubeconfigRequest;
+import com.oracle.bmc.containerengine.responses.CreateKubeconfigResponse;
+import io.micronaut.context.annotation.BootstrapContextCompatible;
+import io.micronaut.context.annotation.Replaces;
+import io.micronaut.context.annotation.Requires;
+import io.micronaut.core.annotation.Nullable;
+import io.micronaut.core.io.ResourceResolver;
+import io.micronaut.kubernetes.client.openapi.config.AbstractKubeConfigLoader;
+import io.micronaut.kubernetes.client.openapi.config.KubeConfig;
+import io.micronaut.kubernetes.client.openapi.config.KubeConfigLoader;
+import jakarta.inject.Singleton;
+import java.io.IOException;
+import java.io.InputStream;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A class for loading a kubeconfig from OKE. It replaces the default kube config loader, which
+ * reads it from a file.
+ *
+ * @since 4.4.x
+ * @author Andriy Dmytruk
+ */
+@Singleton
+@BootstrapContextCompatible
+@Replaces(KubeConfigLoader.class)
+@Requires(beans = OkeKubernetesClientConfig.class)
+final class OkeKubeConfigLoader extends AbstractKubeConfigLoader {
+
+    private static final String TOKEN_VERSION = "2.0.0";
+
+    private static final Logger LOG = LoggerFactory.getLogger(OkeKubeConfigLoader.class);
+    private final ContainerEngineClient client;
+    private final OkeKubernetesClientConfig config;
+
+    /**
+     * Create Kubeconfig loader.
+     *
+     * @param containerEngineClient The client to use to get kubeconfig
+     * @param config The configuration
+     * @param resourceResolver The resource resolver.
+     */
+    OkeKubeConfigLoader(
+            ContainerEngineClient containerEngineClient,
+            OkeKubernetesClientConfig config,
+            ResourceResolver resourceResolver
+    ) {
+        super(resourceResolver);
+        this.client = containerEngineClient;
+        this.config = config;
+    }
+
+    @Override
+    protected @Nullable KubeConfig loadKubeConfig() {
+        return createCubeConfig(config.clusterId(), config.endpointType());
+    }
+
+    /**
+     * A method that uses the container engine client to create a kube config and write it to the
+     * file specified by the environment variable.
+     *
+     * @param okeClusterId The cluster ID
+     * @param endpointType The endpoint type
+     * @return The kubeconfig
+     */
+    protected KubeConfig createCubeConfig(String okeClusterId, Endpoint endpointType) {
+        LOG.info("Creating remote kubeconfig for cluster id {}", okeClusterId);
+        CreateClusterKubeconfigContentDetails body = CreateClusterKubeconfigContentDetails.builder()
+                .tokenVersion(TOKEN_VERSION)
+                .endpoint(endpointType)
+                .build();
+        CreateKubeconfigRequest kubeConfigRequest = CreateKubeconfigRequest.builder()
+                .clusterId(okeClusterId)
+                .createClusterKubeconfigContentDetails(body)
+                .build();
+
+        CreateKubeconfigResponse response;
+        try {
+            response = client.createKubeconfig(kubeConfigRequest);
+        } catch (Exception e) {
+            LOG.error("Caught exception when creating kubeconfig for cluster: {}", okeClusterId, e);
+            throw new IllegalStateException("Unable to create KubeConfig", e);
+        }
+        LOG.info("Successfully received kubeconfig response for cluster id {}", okeClusterId);
+        try (InputStream kubeConfig = response.getInputStream()) {
+            return loadKubeConfigFromInputStream(kubeConfig);
+        } catch (IOException e) {
+            LOG.error("Caught exception when reading kubeconfig for cluster {}", okeClusterId, e);
+            throw new RuntimeException("Unable to create kubeClient", e);
+        }
+    }
+
+}

oraclecloud-oke-kubernetes-client/src/main/java/io/micronaut/oraclecloud/oke/kubernetes/client/OkeKubernetesClientConfig.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2017-2024 original authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micronaut.oraclecloud.oke.kubernetes.client;
+
+import com.oracle.bmc.containerengine.model.CreateClusterKubeconfigContentDetails.Endpoint;
+import io.micronaut.context.annotation.BootstrapContextCompatible;
+import io.micronaut.context.annotation.ConfigurationProperties;
+import io.micronaut.context.annotation.Requires;
+import io.micronaut.core.annotation.NonNull;
+import io.micronaut.core.annotation.Nullable;
+import io.micronaut.core.bind.annotation.Bindable;
+import io.micronaut.core.util.StringUtils;
+import jakarta.validation.constraints.NotBlank;
+
+/**
+ * Configuration for the OKE kubernetes client.
+ * If enabled, the client will retrieve a kubeconfig from the cluster and sign tokens
+ * with the OCI SDK authentication. This is not required on kubernetes nodes, as there
+ * kubeconfig should already be present.
+ *
+ * @param enabled Whether the client is enabled
+ * @param clusterId The OKE cluster ID
+ * @param endpointType Define which endpoint type to use. One of {@code PublicEndpoint},
+ *                     {@code PrivateEndpoint}, {@code VcnHostname} and {@code LegacyKubernetes}.
+ *                     Default is {@code PublicEndpoint}.
+ *
+ * @since 4.4.x
+ * @author Andriy Dmytruk
+ */
+@Requires(property = OkeKubernetesClientConfig.ENABLED, value = StringUtils.TRUE, defaultValue = StringUtils.TRUE)
+@Requires(property = OkeKubernetesClientConfig.CLUSTER_ID)
+@ConfigurationProperties(OkeKubernetesClientConfig.PREFIX)
+@BootstrapContextCompatible
+public record OkeKubernetesClientConfig(
+        @Bindable(defaultValue = StringUtils.TRUE)
+        boolean enabled,
+        @NonNull @NotBlank
+        String clusterId,
+        @Nullable @Bindable(defaultValue = "PublicEndpoint")
+        Endpoint endpointType
+) {
+
+    public static final String PREFIX = "oci.oke.kubernetes.client";
+    public static final String ENABLED = PREFIX + ".enabled";
+    public static final String CLUSTER_ID = PREFIX + ".cluster-id";
+
+}