HADOOP-14944. Add JvmMetrics to KMS.

(cherry picked from commit 86ee0c5e4e304d9551a24a3d8b9161ca1502b70e)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/metrics2/source/JvmMetrics.java

@@ -58,6 +58,11 @@ public class JvmMetrics implements MetricsSource {
       }
       return impl;
     }
+
+    synchronized void shutdown() {
+      DefaultMetricsSystem.instance().unregisterSource(JvmMetrics.name());
+      impl = null;
+    }
   }
 
   @VisibleForTesting
@@ -81,6 +86,7 @@ public class JvmMetrics implements MetricsSource {
   final ConcurrentHashMap<String, MetricsInfo[]> gcInfoCache =
       new ConcurrentHashMap<String, MetricsInfo[]>();
 
+  @VisibleForTesting
   JvmMetrics(String processName, String sessionId) {
     this.processName = processName;
     this.sessionId = sessionId;
@@ -104,6 +110,16 @@ public class JvmMetrics implements MetricsSource {
     return Singleton.INSTANCE.init(processName, sessionId);
   }
 
+  /**
+   * Shutdown the JvmMetrics singleton. This is not necessary if the JVM itself
+   * is shutdown, but may be necessary for scenarios where JvmMetrics instance
+   * needs to be re-created while the JVM is still around. One such scenario
+   * is unit-testing.
+   */
+  public static void shutdownSingleton() {
+    Singleton.INSTANCE.shutdown();
+  }
+
   @Override
   public void getMetrics(MetricsCollector collector, boolean all) {
     MetricsRecordBuilder rb = collector.addRecord(JvmMetrics)

hadoop-common-project/hadoop-kms/src/main/java/org/apache/hadoop/crypto/key/kms/server/KMSConfiguration.java

@@ -76,6 +76,15 @@ public class KMSConfiguration {
   public static final String KMS_AUDIT_AGGREGATION_WINDOW = CONFIG_PREFIX +
       "audit.aggregation.window.ms";
 
+  // Process name shown in metrics
+  public static final String METRICS_PROCESS_NAME_KEY =
+      CONFIG_PREFIX + "metrics.process.name";
+  public static final String METRICS_PROCESS_NAME_DEFAULT = "KMS";
+
+  // Session id for metrics
+  public static final String METRICS_SESSION_ID_KEY =
+      CONFIG_PREFIX + "metrics.session.id";
+
   // KMS Audit logger classes to use
   public static final String KMS_AUDIT_LOGGER_KEY = CONFIG_PREFIX +
       "audit.logger";

hadoop-common-project/hadoop-kms/src/main/java/org/apache/hadoop/crypto/key/kms/server/KMSWebServer.java

@@ -27,12 +27,19 @@ import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.ConfigurationWithLogging;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.http.HttpServer2;
+import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
+import org.apache.hadoop.metrics2.source.JvmMetrics;
 import org.apache.hadoop.security.authorize.AccessControlList;
 import org.apache.hadoop.security.ssl.SSLFactory;
+import org.apache.hadoop.util.JvmPauseMonitor;
 import org.apache.hadoop.util.StringUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import static org.apache.hadoop.crypto.key.kms.server.KMSConfiguration.METRICS_PROCESS_NAME_DEFAULT;
+import static org.apache.hadoop.crypto.key.kms.server.KMSConfiguration.METRICS_PROCESS_NAME_KEY;
+import static org.apache.hadoop.crypto.key.kms.server.KMSConfiguration.METRICS_SESSION_ID_KEY;
+
 /**
  * The KMS web server.
  */
@@ -46,6 +53,9 @@ public class KMSWebServer {
 
   private final HttpServer2 httpServer;
   private final String scheme;
+  private final String processName;
+  private final String sessionId;
+  private final JvmPauseMonitor pauseMonitor;
 
   KMSWebServer(Configuration conf, Configuration sslConf) throws Exception {
     // Override configuration with deprecated environment variables.
@@ -73,6 +83,11 @@ public class KMSWebServer {
     boolean sslEnabled = conf.getBoolean(KMSConfiguration.SSL_ENABLED_KEY,
         KMSConfiguration.SSL_ENABLED_DEFAULT);
     scheme = sslEnabled ? HttpServer2.HTTPS_SCHEME : HttpServer2.HTTP_SCHEME;
+    processName =
+        conf.get(METRICS_PROCESS_NAME_KEY, METRICS_PROCESS_NAME_DEFAULT);
+    sessionId = conf.get(METRICS_SESSION_ID_KEY);
+    pauseMonitor = new JvmPauseMonitor();
+    pauseMonitor.init(conf);
 
     String host = conf.get(KMSConfiguration.HTTP_HOST_KEY,
         KMSConfiguration.HTTP_HOST_DEFAULT);
@@ -113,6 +128,11 @@ public class KMSWebServer {
 
   public void start() throws IOException {
     httpServer.start();
+
+    DefaultMetricsSystem.initialize(processName);
+    final JvmMetrics jm = JvmMetrics.initSingleton(processName, sessionId);
+    jm.setPauseMonitor(pauseMonitor);
+    pauseMonitor.start();
   }
 
   public boolean isRunning() {
@@ -125,6 +145,10 @@ public class KMSWebServer {
 
   public void stop() throws Exception {
     httpServer.stop();
+
+    pauseMonitor.stop();
+    JvmMetrics.shutdownSingleton();
+    DefaultMetricsSystem.shutdown();
   }
 
   public URL getKMSUrl() {

hadoop-common-project/hadoop-kms/src/test/java/org/apache/hadoop/crypto/key/kms/server/TestKMS.java

@@ -98,6 +98,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.mockito.Mockito.when;
 
@@ -2693,4 +2694,38 @@ public class TestKMS {
     });
   }
 
+  /*
+   * Test the jmx page can return, and contains the basic JvmMetrics. Only
+   * testing in simple mode since the page content is the same, kerberized
+   * or not.
+   */
+  @Test
+  public void testKMSJMX() throws Exception {
+    Configuration conf = new Configuration();
+    final File confDir = getTestDir();
+    conf = createBaseKMSConf(confDir, conf);
+    final String processName = "testkmsjmx";
+    conf.set(KMSConfiguration.METRICS_PROCESS_NAME_KEY, processName);
+    writeConf(confDir, conf);
+
+    runServer(null, null, confDir, new KMSCallable<Void>() {
+      @Override
+      public Void call() throws Exception {
+        final URL jmxUrl = new URL(
+            getKMSUrl() + "/jmx?user.name=whatever&qry=Hadoop:service="
+                + processName + ",name=JvmMetrics");
+        LOG.info("Requesting jmx from " + jmxUrl);
+        final StringBuilder sb = new StringBuilder();
+        final InputStream in = jmxUrl.openConnection().getInputStream();
+        final byte[] buffer = new byte[64 * 1024];
+        int len;
+        while ((len = in.read(buffer)) > 0) {
+          sb.append(new String(buffer, 0, len));
+        }
+        LOG.info("jmx returned: " + sb.toString());
+        assertTrue(sb.toString().contains("JvmMetrics"));
+        return null;
+      }
+    });
+  }
 }