Merge branch 'zkbesu' into clique-simulate-block-production

metrics/core/src/main/java/org/hyperledger/besu/metrics/noop/NoOpMetricsSystem.java

@@ -17,6 +17,7 @@
 import org.hyperledger.besu.metrics.ObservableMetricsSystem;
 import org.hyperledger.besu.metrics.Observation;
 import org.hyperledger.besu.plugin.services.metrics.Counter;
+import org.hyperledger.besu.plugin.services.metrics.Histogram;
 import org.hyperledger.besu.plugin.services.metrics.LabelledGauge;
 import org.hyperledger.besu.plugin.services.metrics.LabelledMetric;
 import org.hyperledger.besu.plugin.services.metrics.MetricCategory;
@@ -45,6 +46,9 @@ public class NoOpMetricsSystem implements ObservableMetricsSystem {
   /** The constant NO_OP_OPERATION_TIMER. */
   public static final OperationTimer NO_OP_OPERATION_TIMER = () -> NO_OP_TIMING_CONTEXT;
 
+  /** The constant NO_OP_HISTOGRAM. */
+  public static final Histogram NO_OP_HISTOGRAM = d -> {};
+
   /** The constant NO_OP_LABELLED_1_COUNTER. */
   public static final LabelledMetric<Counter> NO_OP_LABELLED_1_COUNTER =
       new LabelCountingNoOpMetric<>(1, NO_OP_COUNTER);
@@ -61,6 +65,10 @@ public class NoOpMetricsSystem implements ObservableMetricsSystem {
   public static final LabelledMetric<OperationTimer> NO_OP_LABELLED_1_OPERATION_TIMER =
       new LabelCountingNoOpMetric<>(1, NO_OP_OPERATION_TIMER);
 
+  /** The constant NO_OP_LABELLED_1_HISTOGRAM. */
+  public static final LabelledMetric<Histogram> NO_OP_LABELLED_1_HISTOGRAM =
+      new LabelCountingNoOpMetric<>(1, NO_OP_HISTOGRAM);
+
   /** The constant NO_OP_LABELLED_1_GAUGE. */
   public static final LabelledGauge NO_OP_LABELLED_1_GAUGE =
       new LabelledGaugeNoOpMetric(1, NO_OP_GAUGE);
@@ -137,13 +145,37 @@ public static LabelledMetric<OperationTimer> getOperationTimerLabelledMetric(
     }
   }
 
+  /**
+   * Gets histogram labelled metric.
+   *
+   * @param labelCount the label count
+   * @return the histogram labelled metric
+   */
+  public static LabelledMetric<Histogram> getHistogramLabelledMetric(final int labelCount) {
+    if (labelCount == 1) {
+      return NO_OP_LABELLED_1_HISTOGRAM;
+    } else {
+      return new LabelCountingNoOpMetric<>(labelCount, NO_OP_HISTOGRAM);
+    }
+  }
+
   @Override
   public void createGauge(
       final MetricCategory category,
       final String name,
       final String help,
       final DoubleSupplier valueSupplier) {}
 
+  @Override
+  public LabelledMetric<Histogram> createLabelledHistogram(
+      final MetricCategory category,
+      final String name,
+      final String help,
+      final double[] buckets,
+      final String... labelNames) {
+    return null;
+  }
+
   @Override
   public LabelledGauge createLabelledGauge(
       final MetricCategory category,

metrics/core/src/main/java/org/hyperledger/besu/metrics/opentelemetry/OpenTelemetrySystem.java

@@ -20,6 +20,7 @@
 import org.hyperledger.besu.metrics.StandardMetricCategory;
 import org.hyperledger.besu.metrics.noop.NoOpMetricsSystem;
 import org.hyperledger.besu.plugin.services.metrics.Counter;
+import org.hyperledger.besu.plugin.services.metrics.Histogram;
 import org.hyperledger.besu.plugin.services.metrics.LabelledGauge;
 import org.hyperledger.besu.plugin.services.metrics.LabelledMetric;
 import org.hyperledger.besu.plugin.services.metrics.MetricCategory;
@@ -277,6 +278,16 @@ public void createGauge(
     }
   }
 
+  @Override
+  public LabelledMetric<Histogram> createLabelledHistogram(
+      final MetricCategory category,
+      final String name,
+      final String help,
+      final double[] buckets,
+      final String... labelNames) {
+    return null;
+  }
+
   @Override
   public LabelledGauge createLabelledGauge(
       final MetricCategory category,

metrics/core/src/main/java/org/hyperledger/besu/metrics/prometheus/PrometheusHistogram.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright ConsenSys AG.
+ *
+ * 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
+ *
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package org.hyperledger.besu.metrics.prometheus;
+
+import org.hyperledger.besu.plugin.services.metrics.Histogram;
+import org.hyperledger.besu.plugin.services.metrics.LabelledMetric;
+
+class PrometheusHistogram implements LabelledMetric<Histogram> {
+
+  private final io.prometheus.client.Histogram histogram;
+
+  public PrometheusHistogram(final io.prometheus.client.Histogram histogram) {
+    this.histogram = histogram;
+  }
+
+  @Override
+  public Histogram labels(final String... labels) {
+    return new UnlabelledHistogram(histogram.labels(labels));
+  }
+
+  private static class UnlabelledHistogram implements Histogram {
+    private final io.prometheus.client.Histogram.Child amount;
+
+    private UnlabelledHistogram(final io.prometheus.client.Histogram.Child amount) {
+      this.amount = amount;
+    }
+
+    @Override
+    public void observe(final double amount) {
+      this.amount.observe(amount);
+    }
+  }
+}

metrics/core/src/main/java/org/hyperledger/besu/metrics/prometheus/PrometheusMetricsSystem.java

@@ -59,6 +59,8 @@ public class PrometheusMetricsSystem implements ObservableMetricsSystem {
       cachedCounters = new ConcurrentHashMap<>();
   private final Map<String, LabelledMetric<OperationTimer>> cachedTimers =
       new ConcurrentHashMap<>();
+  private final Map<String, LabelledMetric<org.hyperledger.besu.plugin.services.metrics.Histogram>>
+      cachedHistograms = new ConcurrentHashMap<>();
   private final Set<String> totalSuffixedCounters = new ConcurrentHashSet<>();
 
   private final Set<MetricCategory> enabledCategories;
@@ -111,6 +113,29 @@ public LabelledMetric<org.hyperledger.besu.plugin.services.metrics.Counter> crea
         });
   }
 
+  @Override
+  public LabelledMetric<org.hyperledger.besu.plugin.services.metrics.Histogram>
+      createLabelledHistogram(
+          final MetricCategory category,
+          final String name,
+          final String help,
+          final double[] buckets,
+          final String... labelNames) {
+    final String metricName = convertToPrometheusName(category, name);
+    return cachedHistograms.computeIfAbsent(
+        metricName,
+        k -> {
+          if (isCategoryEnabled(category)) {
+            final Histogram histogram =
+                Histogram.build(metricName, help).labelNames(labelNames).buckets(buckets).create();
+            addCollectorUnchecked(category, histogram);
+            return new PrometheusHistogram(histogram);
+          } else {
+            return NoOpMetricsSystem.getHistogramLabelledMetric(labelNames.length);
+          }
+        });
+  }
+
   @Override
   public LabelledMetric<OperationTimer> createLabelledTimer(
       final MetricCategory category,

metrics/core/src/test-support/java/org/hyperledger/besu/metrics/StubMetricsSystem.java

@@ -18,6 +18,7 @@
 
 import org.hyperledger.besu.metrics.noop.NoOpMetricsSystem;
 import org.hyperledger.besu.plugin.services.metrics.Counter;
+import org.hyperledger.besu.plugin.services.metrics.Histogram;
 import org.hyperledger.besu.plugin.services.metrics.LabelledGauge;
 import org.hyperledger.besu.plugin.services.metrics.LabelledMetric;
 import org.hyperledger.besu.plugin.services.metrics.MetricCategory;
@@ -93,6 +94,16 @@ public void createGauge(
     gauges.put(name, valueSupplier);
   }
 
+  @Override
+  public LabelledMetric<Histogram> createLabelledHistogram(
+      final MetricCategory category,
+      final String name,
+      final String help,
+      final double[] buckets,
+      final String... labelNames) {
+    return null;
+  }
+
   public double getGaugeValue(final String name) {
     final DoubleSupplier gauge = gauges.get(name);
     if (gauge == null) {

plugin-api/build.gradle

@@ -71,7 +71,7 @@ Calculated : ${currentHash}
 tasks.register('checkAPIChanges', FileStateChecker) {
   description = "Checks that the API for the Plugin-API project does not change without deliberate thought"
   files = sourceSets.main.allJava.files
-  knownHash = '8rPIE3fYl48RPRQXxYhMk559e/r+wHSKU9bGSJmruKQ='
+  knownHash = '2CKmXhWO+/sZMuA3QpJGvOQVi5t3RA5x72aXoYBIzkU='
 }
 check.dependsOn('checkAPIChanges')
 

plugin-api/src/main/java/org/hyperledger/besu/plugin/services/MetricsSystem.java

@@ -15,6 +15,7 @@
 package org.hyperledger.besu.plugin.services;
 
 import org.hyperledger.besu.plugin.services.metrics.Counter;
+import org.hyperledger.besu.plugin.services.metrics.Histogram;
 import org.hyperledger.besu.plugin.services.metrics.LabelledGauge;
 import org.hyperledger.besu.plugin.services.metrics.LabelledMetric;
 import org.hyperledger.besu.plugin.services.metrics.MetricCategory;
@@ -159,4 +160,17 @@ default void createLongGauge(
       final LongSupplier valueSupplier) {
     createGauge(category, name, help, () -> (double) valueSupplier.getAsLong());
   }
+
+  /**
+   * Creates a histogram with assigned labels
+   *
+   * @param category The {@link MetricCategory} this histogram is assigned to.
+   * @param name A name for this metric.
+   * @param help A human-readable description of the metric.
+   * @param buckets An array of buckets to assign to the histogram
+   * @param labelNames An array of labels to assign to the histogram.
+   * @return The labelled histogram.
+   */
+  LabelledMetric<Histogram> createLabelledHistogram(
+      MetricCategory category, String name, String help, double[] buckets, String... labelNames);
 }

plugin-api/src/main/java/org/hyperledger/besu/plugin/services/metrics/Histogram.java

@@ -0,0 +1,29 @@
+/*
+ * Copyright ConsenSys AG.
+ *
+ * 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
+ *
+ * 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.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package org.hyperledger.besu.plugin.services.metrics;
+
+/**
+ * A histogram samples observations (usually things like request durations or response sizes) and
+ * counts them in configurable buckets. It also provides a sum of all observed values.
+ */
+public interface Histogram {
+
+  /**
+   * Observe the given amount.
+   *
+   * @param amount the amount
+   */
+  void observe(double amount);
+}