HBASE-27574 Implement ClusterManager interface for Kubernetes

A basic implementation that supports taking destructive actions. Assume that services are running
behind a resilient `Deployment` of some kind, and that the cluster will handle starting up
replacement processes. Requires specification of a scoping namespace.

hbase-it/pom.xml

@@ -32,6 +32,7 @@
   <description>Integration and System tests for HBase</description>
 
   <properties>
+    <k8s.version>17.0.0</k8s.version>
     <!-- Test inclusion patterns used by failsafe configuration -->
     <unittest.include>**/Test*.java</unittest.include>
     <integrationtest.include>**/IntegrationTest*.java</integrationtest.include>
@@ -174,6 +175,24 @@
       <artifactId>javax.servlet-api</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>io.kubernetes</groupId>
+      <artifactId>client-java</artifactId>
+      <version>${k8s.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>io.kubernetes</groupId>
+      <artifactId>client-java-api</artifactId>
+      <version>${k8s.version}</version>
+      <scope>test</scope>
+      <exclusions>
+        <exclusion>
+          <groupId>com.google.code.findbugs</groupId>
+          <artifactId>jsr305</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>

hbase-it/src/test/java/org/apache/hadoop/hbase/KubernetesClusterManager.java

@@ -0,0 +1,258 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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
+ *
+ *     http://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 org.apache.hadoop.hbase;
+
+import com.google.gson.JsonSyntaxException;
+import io.kubernetes.client.openapi.ApiClient;
+import io.kubernetes.client.openapi.ApiException;
+import io.kubernetes.client.openapi.apis.CoreV1Api;
+import io.kubernetes.client.openapi.models.V1ObjectMeta;
+import io.kubernetes.client.openapi.models.V1Pod;
+import io.kubernetes.client.openapi.models.V1PodList;
+import io.kubernetes.client.util.ClientBuilder;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Optional;
+import java.util.Set;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.conf.Configured;
+import org.apache.hadoop.hbase.procedure2.util.StringUtils;
+import org.apache.yetus.audience.InterfaceAudience;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Cluster manager for K8s context. Supports taking destructive actions, and checking for the
+ * presence of a running process. Assumes services are running behind some type of `Deployment` that
+ * will handle starting replacement processes after a destructive action. Requires that the
+ * configuration specify a Kubernetes namespace.
+ * </p>
+ * Note that the k8s java client is a bit dodgy unable to read responses when we call delete (i.e.
+ * kill) and sometimes when checking isRunning; makes for noisy logs and sometimes the operations
+ * overrun each other but generally succeed.
+ */
+@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
+public class KubernetesClusterManager extends Configured implements ClusterManager {
+  private static final Logger LOG = LoggerFactory.getLogger(KubernetesClusterManager.class);
+
+  private static final String NAMESPACE_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".namespace";
+  private static final String ZOOKEEPER_ROLE_SELECTOR_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".zookeeper_role";
+  private static final String NAMENODE_ROLE_SELECTOR_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".namenode_role";
+  private static final String JOURNALNODE_ROLE_SELECTOR_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".journalnode_role";
+  private static final String DATANODE_ROLE_SELECTOR_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".datanode_role";
+  private static final String MASTER_ROLE_SELECTOR_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".master_role";
+  private static final String REGIONSERVER_ROLE_SELECTOR_CONF_KEY =
+    KubernetesClusterManager.class.getCanonicalName() + ".regionserver_role";
+  private static final Set<ServiceType> SUPPORTED_SERVICE_TYPES = buildSupportedServiceTypesSet();
+
+  private CoreV1Api api;
+  private String namespace;
+
+  private static Set<ServiceType> buildSupportedServiceTypesSet() {
+    final Set<ServiceType> set = new HashSet<>();
+    set.add(ServiceType.ZOOKEEPER_SERVER);
+    set.add(ServiceType.HADOOP_NAMENODE);
+    set.add(ServiceType.HADOOP_JOURNALNODE);
+    set.add(ServiceType.HADOOP_DATANODE);
+    set.add(ServiceType.HBASE_MASTER);
+    set.add(ServiceType.HBASE_REGIONSERVER);
+    return Collections.unmodifiableSet(set);
+  }
+
+  @Override
+  public void setConf(Configuration configuration) {
+    // This is usually called from the constructor (The call to super goes to
+    // Configured which does a setConf in its construction) but the configuration
+    // null at that time. After construction, setConf is called again.
+    // Assume single-thread doing ClusterManager setup.
+    if (configuration == null) {
+      LOG.debug("Skipping because provided configuration=null");
+      return;
+    }
+    if (getConf() != null) {
+      LOG.debug("Skipping because configuration already set, getConf={}", getConf());
+      return;
+    }
+    super.setConf(configuration);
+    this.namespace = configuration.get(NAMESPACE_CONF_KEY);
+    LOG.info(
+      "Configuration={}, namespace={}, hbase.rootdir={}, hbase.zookeeper.quorum={}, "
+        + "hbase.client.zookeeper.quorum={}",
+      configuration, this.namespace, configuration.get("hbase.rootdir"),
+      configuration.get("hbase.zookeeper.quorum"),
+      configuration.get("hbase.client.zookeeper.quorum"));
+    final CoreV1Api coreV1Api;
+    try {
+      ApiClient client = ClientBuilder.cluster().build();
+      io.kubernetes.client.openapi.Configuration.setDefaultApiClient(client);
+      coreV1Api = new CoreV1Api();
+    } catch (IOException ioe) {
+      throw new RuntimeException("Failed Kubernetes ApiClient construction", ioe);
+    }
+    this.api = coreV1Api;
+  }
+
+  @Override
+  public void start(ServiceType service, String hostname, int port) {
+    assertSupportedServiceType(service);
+    // presumably kubernetes is automatically starting pods, so nothing to do here.
+  }
+
+  @Override
+  public void stop(ServiceType service, String hostname, int port) throws IOException {
+    assertSupportedServiceType(service);
+    kill(hostname);
+  }
+
+  @Override
+  public void restart(ServiceType service, String hostname, int port) throws IOException {
+    assertSupportedServiceType(service);
+    kill(hostname);
+  }
+
+  @Override
+  public void kill(ServiceType service, String hostname, int port) throws IOException {
+    assertSupportedServiceType(service);
+    kill(hostname);
+  }
+
+  @Override
+  public void suspend(ServiceType service, String hostname, int port) {
+    throw unsupportedActionType("suspend");
+  }
+
+  @Override
+  public void resume(ServiceType service, String hostname, int port) {
+    throw unsupportedActionType("resume");
+  }
+
+  @Override
+  public boolean isRunning(ServiceType service, String hostname, int port) throws IOException {
+    final String roleSelector = roleSelectorForServiceType(service);
+    return isRunning(roleSelector, hostname);
+  }
+
+  private String roleSelectorForServiceType(final ServiceType serviceType) {
+    assertSupportedServiceType(serviceType);
+    switch (serviceType) {
+      case HADOOP_NAMENODE:
+        return getConf().get(NAMENODE_ROLE_SELECTOR_CONF_KEY, "namenode");
+      case HADOOP_DATANODE:
+        return getConf().get(DATANODE_ROLE_SELECTOR_CONF_KEY, "datanode");
+      case HADOOP_JOURNALNODE:
+        return getConf().get(JOURNALNODE_ROLE_SELECTOR_CONF_KEY, "journalnode");
+      case ZOOKEEPER_SERVER:
+        return getConf().get(ZOOKEEPER_ROLE_SELECTOR_CONF_KEY, "zookeeper");
+      case HBASE_MASTER:
+        return getConf().get(MASTER_ROLE_SELECTOR_CONF_KEY, "master");
+      case HBASE_REGIONSERVER:
+        return getConf().get(REGIONSERVER_ROLE_SELECTOR_CONF_KEY, "regionserver");
+      default:
+        throw new RuntimeException("should not happen");
+    }
+  }
+
+  private boolean isRunning(String roleSelector, String hostname) throws IOException {
+    if (api == null) {
+      return false;
+    }
+    final V1PodList list;
+    try {
+      list = api.listNamespacedPod(namespace, null, null, null, null,
+        "role in (" + roleSelector + ")", null, null, null, null, null);
+    } catch (ApiException e) {
+      throw convertApiException(e);
+    }
+    if (list == null) {
+      return false;
+    }
+    for (V1Pod item : list.getItems()) {
+      final String podName =
+        Optional.ofNullable(item).map(V1Pod::getMetadata).map(V1ObjectMeta::getName).orElse(null);
+      if (StringUtils.isEmpty(podName)) {
+        LOG.warn("Listing of namespace '{}' contains entry with empty pod name.", namespace);
+        continue;
+      }
+      if (hostname.startsWith(podName)) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * @param hostname fully qualified hostname of the target pod.
+   * @return The pod name without the domain.
+   */
+  private static String hostNameToPodName(String hostname) {
+    return hostname.substring(0, hostname.indexOf("."));
+  }
+
+  private void kill(String hostname) throws IOException {
+    try {
+      final String podName = hostNameToPodName(hostname);
+      LOG.debug("Deleting pod: {}.{}", namespace, podName);
+      api.deleteNamespacedPod(podName, namespace, null, null, null, null, null, null);
+    } catch (JsonSyntaxException e) {
+      handleJsonSyntaxException(e);
+    } catch (ApiException e) {
+      throw convertApiException(e);
+    }
+  }
+
+  /**
+   * See <a href="https://github.com/kubernetes-client/java/issues/86">kubernetes-client/java#86</a>
+   */
+  private void handleJsonSyntaxException(JsonSyntaxException e) throws JsonSyntaxException {
+    if (!(e.getCause() instanceof IllegalStateException)) {
+      throw e;
+    }
+    final IllegalStateException ise = (IllegalStateException) e.getCause();
+    if (
+      ise.getMessage() != null && ise.getMessage().contains("BEGIN_OBJECT")
+        && ise.getMessage().contains("Expected")
+    ) {
+      LOG.info("Operation probably succeeded but parse of result failed, "
+        + "see https://github.com/kubernetes-client/java/issues/86");
+    } else {
+      throw e;
+    }
+  }
+
+  private static IOException convertApiException(final ApiException e) {
+    return new IOException(
+      "response body: " + e.getResponseBody() + ", response code: " + e.getCode(), e);
+  }
+
+  private static RuntimeException unsupportedActionType(final String action) {
+    return new RuntimeException("Unable to service request for action=" + action);
+  }
+
+  private static void assertSupportedServiceType(final ServiceType serviceType) {
+    if (!SUPPORTED_SERVICE_TYPES.contains(serviceType)) {
+      throw new RuntimeException("Unsupported ServiceType " + serviceType);
+    }
+  }
+}