HDDS-14825. Add Grafana Dashboard and Metrics for ZDU

hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/server/http/BaseHttpServer.java

@@ -329,6 +329,7 @@ public void start() throws IOException {
             .register("prometheus", "Hadoop metrics prometheus exporter",
                 prometheusMetricsSink);
       }
+      BuildInfoMetrics.create(name);
       updateConnectorAddress();
     }
 
@@ -341,6 +342,7 @@ private boolean isEnabled() {
   public void stop() throws Exception {
     if (httpServer != null) {
       httpServer.stop();
+      BuildInfoMetrics.unregister();
     }
   }
 

hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/server/http/BuildInfoMetrics.java

@@ -0,0 +1,101 @@
+/*
+ * 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.hdds.server.http;
+
+import org.apache.hadoop.hdds.utils.HddsVersionInfo;
+import org.apache.hadoop.hdds.utils.VersionInfo;
+import org.apache.hadoop.metrics2.MetricsCollector;
+import org.apache.hadoop.metrics2.MetricsRecordBuilder;
+import org.apache.hadoop.metrics2.MetricsSource;
+import org.apache.hadoop.metrics2.MetricsSystem;
+import org.apache.hadoop.metrics2.MetricsTag;
+import org.apache.hadoop.metrics2.annotation.Metrics;
+import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
+import org.apache.hadoop.metrics2.lib.Interns;
+import org.apache.hadoop.ozone.OzoneConsts;
+
+/**
+ * Exposes build version and git revision as a Prometheus info metric.
+ *
+ * <p>Follows the OpenMetrics Info pattern: the value is always 1, and the
+ * identifying strings are carried as labels. The metric name uses the
+ * conventional {@code _build_info} suffix.</p>
+ *
+ * <pre>
+ * ozone_build_info{component="OM",version="2.0.0",revision="abc1234"} 1
+ * </pre>
+ */
+@Metrics(about = "Ozone build version info", context = OzoneConsts.OZONE)
+public final class BuildInfoMetrics implements MetricsSource {
+
+  public static final String METRICS_SOURCE_NAME = "OzoneBuildInfo";
+  /**
+   * Record name chosen so that prometheusName("Ozone", "BuildInfo") produces
+   * the conventional "ozone_build_info" metric name.
+   */
+  public static final String RECORD_NAME = "Ozone";
+
+  private final String component;
+  private final String version;
+  private final String revision;
+
+  private BuildInfoMetrics(String component, VersionInfo versionInfo) {
+    this.component = component;
+    this.version = versionInfo.getVersion();
+    this.revision = versionInfo.getRevision();
+  }
+
+  /**
+   * Return the existing build-info source if one is already registered,
+   * otherwise create a new one, register it and return it. Build info is
+   * process-wide, so a single source is shared by every {@code BaseHttpServer}
+   * in the JVM (e.g. the S3 Gateway runs two). Making this idempotent keeps a
+   * second caller from failing with a duplicate-source error.
+   *
+   * @return a new or existing {@link BuildInfoMetrics}
+   */
+  public static synchronized BuildInfoMetrics create(String component) {
+    MetricsSystem ms = DefaultMetricsSystem.instance();
+    MetricsSource existing = ms.getSource(METRICS_SOURCE_NAME);
+    if (existing != null) {
+      return (BuildInfoMetrics) existing;
+    }
+    BuildInfoMetrics source =
+        new BuildInfoMetrics(component, HddsVersionInfo.HDDS_VERSION_INFO);
+    return ms.register(METRICS_SOURCE_NAME, "Ozone build version info", source);
+  }
+
+  /**
+   * Unregister the build-info source. Idempotent: a no-op if it was never
+   * registered or was already removed. Called when the owning server stops so
+   * that a later {@link #create(String)} does not fail with a duplicate source.
+   */
+  public static synchronized void unregister() {
+    DefaultMetricsSystem.instance().unregisterSource(METRICS_SOURCE_NAME);
+  }
+
+  @Override
+  public void getMetrics(MetricsCollector collector, boolean all) {
+    MetricsRecordBuilder builder = collector.addRecord(RECORD_NAME)
+        .add(new MetricsTag(Interns.info("component", "Ozone component name"), component))
+        .add(new MetricsTag(Interns.info("revision", "Source control revision"), revision))
+        .add(new MetricsTag(Interns.info("version", "Ozone build version"), version))
+        .addGauge(Interns.info("BuildInfo", "Always 1; identifying info is in labels"), 1L);
+    builder.endRecord();
+  }
+}

hadoop-hdds/framework/src/test/java/org/apache/hadoop/hdds/server/http/TestBuildInfoMetrics.java

@@ -0,0 +1,117 @@
+/*
+ * 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.hdds.server.http;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+import java.util.concurrent.TimeoutException;
+import org.apache.hadoop.metrics2.MetricsSystem;
+import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
+import org.apache.ozone.test.GenericTestUtils;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests for {@link BuildInfoMetrics}.
+ */
+public class TestBuildInfoMetrics {
+
+  private MetricsSystem metricsSystem;
+  private PrometheusMetricsSink sink;
+
+  @BeforeEach
+  public void setUp() {
+    metricsSystem = DefaultMetricsSystem.instance();
+    metricsSystem.init("test");
+    sink = new PrometheusMetricsSink("testserver");
+    metricsSystem.register("Prometheus", "Prometheus", sink);
+  }
+
+  @AfterEach
+  public void tearDown() {
+    metricsSystem.unregisterSource(BuildInfoMetrics.METRICS_SOURCE_NAME);
+    metricsSystem.stop();
+    metricsSystem.shutdown();
+  }
+
+  @Test
+  public void testBuildInfoMetricPublished()
+      throws IOException, InterruptedException, TimeoutException {
+    BuildInfoMetrics.create("OM");
+
+    String output = waitForMetricsToPublish("ozone_build_info");
+
+    assertThat(output).contains("# TYPE ozone_build_info gauge");
+    assertThat(output).contains("ozone_build_info{");
+    assertThat(output).contains("component=\"OM\"");
+    assertThat(output).contains("version=");
+    assertThat(output).contains("revision=");
+    // Info metrics always have value 1
+    assertThat(output).containsPattern("ozone_build_info\\{.*\\} 1");
+  }
+
+  @Test
+  public void testBuildInfoMetricOnlyOneTypeComment()
+      throws IOException, InterruptedException, TimeoutException {
+    BuildInfoMetrics.create("SCM");
+
+    String output = waitForMetricsToPublish("ozone_build_info");
+
+    assertEquals(1, countOccurrences(output, "# TYPE ozone_build_info gauge"),
+        "Expected exactly one TYPE comment for ozone_build_info");
+  }
+
+  private String publishAndGet() throws IOException {
+    metricsSystem.publishMetricsNow();
+    ByteArrayOutputStream bos = new ByteArrayOutputStream();
+    OutputStreamWriter writer = new OutputStreamWriter(bos, UTF_8);
+    sink.writeMetrics(writer);
+    writer.flush();
+    return bos.toString(UTF_8.name());
+  }
+
+  private String waitForMetricsToPublish(String metric)
+      throws InterruptedException, TimeoutException {
+    String[] result = new String[1];
+    GenericTestUtils.waitFor(() -> {
+      try {
+        result[0] = publishAndGet();
+      } catch (IOException e) {
+        throw new RuntimeException(e);
+      }
+      return result[0].contains(metric);
+    }, 500, 30000);
+    return result[0];
+  }
+
+  private static int countOccurrences(String text, String substring) {
+    int count = 0;
+    int idx = 0;
+    while ((idx = text.indexOf(substring, idx)) != -1) {
+      count++;
+      idx += substring.length();
+    }
+    return count;
+  }
+}

hadoop-hdds/server-scm/src/main/java/org/apache/hadoop/hdds/scm/container/placement/metrics/SCMMetrics.java

@@ -180,7 +180,6 @@ public void addRatisEvent(String event) {
     }
   }
 
-  @Metric("Ratis state machine events")
   public String getRatisEvents() {
     synchronized (ratisEvents) {
       return String.join("\n", ratisEvents);