IGNITE-29229 Add AssertionErrorCount monitoring metric to detect AssertionError occurrences in the JVM

docs/_docs/monitoring-metrics/new-metrics.adoc

@@ -25,6 +25,7 @@ Register name: `sys`
 [cols="2,1,3",opts="header"]
 |===
 |Name | Type | Description
+|AssertionErrorCount | long | Number of AssertionErrors thrown in this JVM.
 |CpuLoad | double | CPU load.
 |CurrentThreadCpuTime | long | CPU time of the thread that reads the metric, in nanoseconds.
 |CurrentThreadUserTime | long | User-mode CPU time of the thread that reads the metric, in nanoseconds.

modules/core/src/main/java/org/apache/ignite/internal/processors/metric/GridMetricManager.java

@@ -28,10 +28,13 @@
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.function.Consumer;
 import java.util.function.Supplier;
+import jdk.jfr.consumer.RecordedClass;
+import jdk.jfr.consumer.RecordingStream;
 import org.apache.ignite.IgniteCheckedException;
 import org.apache.ignite.IgniteException;
 import org.apache.ignite.internal.GridKernalContext;
@@ -45,6 +48,7 @@
 import org.apache.ignite.internal.processors.metric.impl.AtomicLongMetric;
 import org.apache.ignite.internal.processors.metric.impl.DoubleMetricImpl;
 import org.apache.ignite.internal.processors.metric.impl.HitRateMetric;
+import org.apache.ignite.internal.processors.metric.impl.LongAdderMetric;
 import org.apache.ignite.internal.processors.metric.impl.MaxValueMetric;
 import org.apache.ignite.internal.processors.metric.impl.MetricUtils;
 import org.apache.ignite.internal.processors.timeout.GridTimeoutProcessor;
@@ -142,6 +146,9 @@ public class GridMetricManager extends GridManagerAdapter<MetricExporterSpi> imp
     /** Custom metrics registry name. */
     public static final String CUSTOM_METRICS = "custom";
 
+    /** Metric name for the count of AssertionErrors thrown in the JVM. */
+    public static final String ASSERTION_ERROR_CNT = "AssertionErrorCount";
+
     /** JVM interface to memory consumption info */
     private static final MemoryMXBean mem = ManagementFactory.getMemoryMXBean();
 
@@ -202,6 +209,12 @@ public class GridMetricManager extends GridManagerAdapter<MetricExporterSpi> imp
     /** */
     private final IgniteMetrics customMetrics;
 
+    /** AssertionError counter. */
+    private final LongAdderMetric assertionErrorCnt;
+
+    /** JFR stream for capturing thrown Errors. */
+    private volatile RecordingStream jfrStream;
+
     /**
      * @param ctx Kernal context.
      */
@@ -247,6 +260,8 @@ public GridMetricManager(GridKernalContext ctx) {
             "CPU time of the thread that reads the metric, in nanoseconds.");
         sysreg.register("CurrentThreadUserTime", threads::getCurrentThreadUserTime,
             "User-mode CPU time of the thread that reads the metric, in nanoseconds.");
+        assertionErrorCnt = sysreg.longAdderMetric(ASSERTION_ERROR_CNT,
+                "Number of AssertionErrors thrown in this JVM.");
 
         MetricRegistryImpl pmeReg = registry(PME_METRICS);
 
@@ -273,6 +288,8 @@ public GridMetricManager(GridKernalContext ctx) {
 
         startSpi();
 
+        startJfrErrorStream();
+
         // In case standalone kernal start.
         if (ctx.internalSubscriptionProcessor() == null)
             return;
@@ -323,6 +340,35 @@ public GridMetricManager(GridKernalContext ctx) {
 
         // Stop discovery worker and metrics updater.
         U.closeQuiet(metricsUpdateTask);
+        U.closeQuiet(jfrStream);
+        jfrStream = null;
+    }
+
+    /**
+     * Starts a JFR RecordingStream to capture thrown Error events and increment the
+     * {@link #assertionErrorCnt} metric when an AssertionError is detected.
+     */
+    private void startJfrErrorStream() {
+        try {
+            RecordingStream stream = new RecordingStream();
+            stream.enable("jdk.JavaErrorThrow");
+            stream.onEvent("jdk.JavaErrorThrow", event -> {
+                try {
+                    RecordedClass cls = event.getClass("thrownClass");
+                    Objects.requireNonNull(cls, "Java error occurs. Unable to get thrown class");
+                    if ("java.lang.AssertionError".equals(cls.getName()))
+                        assertionErrorCnt.increment();
+                }
+                catch (RuntimeException cause) {
+                    log.warning("Failed to monitor Java error event.", cause);
+                }
+            });
+            stream.startAsync();
+            jfrStream = stream;
+        }
+        catch (RuntimeException cause) {
+            U.warn(log, "Failed to start JFR error stream: ", cause);
+        }
     }
 
     /**

modules/core/src/test/java/org/apache/ignite/internal/processors/metric/GridMetricManagerAssertionMetricTest.java

@@ -0,0 +1,98 @@
+/*
+ * 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.ignite.internal.processors.metric;
+
+import org.apache.ignite.internal.IgniteEx;
+import org.apache.ignite.metric.MetricRegistry;
+import org.apache.ignite.spi.metric.LongMetric;
+import org.apache.ignite.testframework.junits.common.GridCommonAbstractTest;
+import org.junit.Test;
+
+import static org.apache.ignite.internal.processors.metric.GridMetricManager.ASSERTION_ERROR_CNT;
+import static org.apache.ignite.internal.processors.metric.GridMetricManager.SYS_METRICS;
+import static org.apache.ignite.testframework.GridTestUtils.waitForCondition;
+
+/**
+ * Tests the ASSERTION_ERROR_CNT metric in the sys metrics registry.
+ */
+public class GridMetricManagerAssertionMetricTest extends GridCommonAbstractTest {
+
+    /**
+     * Verifies that the ASSERTION_ERROR_CNT counter increments
+     * when an AssertionError is thrown.
+     *
+     * @throws Exception If fails.
+     */
+    @Test
+    public void testAssertionErrorMetric() throws Exception {
+        try {
+            IgniteEx grid = startGrid(0);
+
+            MetricRegistry sysReg = grid.context().metric().registry(SYS_METRICS);
+
+            assertNotNull(sysReg);
+
+            LongMetric ctr = sysReg.findMetric(ASSERTION_ERROR_CNT);
+
+            assertNotNull("Metric " + ASSERTION_ERROR_CNT + " not found", ctr);
+
+            long init = ctr.value();
+
+            // Throw an AssertionError.
+            try {
+                throw new AssertionError("test assertion");
+            }
+            catch (AssertionError e) {
+                // Expected.
+            }
+
+            // Metric should increment (JFR events are delivered asynchronously).
+            assertTrue(
+                "Metric should increment after AssertionError",
+                waitForCondition(() -> ctr.value() >= init + 1, getTestTimeout()));
+        }
+        finally {
+            stopAllGrids();
+        }
+    }
+
+    /**
+     * Verifies that the ASSERTION_ERROR_CNT metric exposes proper name and description.
+     *
+     * @throws Exception If fails.
+     */
+    @Test
+    public void testMetricMetadata() throws Exception {
+        try {
+            IgniteEx grid = startGrid(0);
+
+            MetricRegistry sysReg = grid.context().metric().registry(SYS_METRICS);
+
+            LongMetric ctr = sysReg.findMetric(ASSERTION_ERROR_CNT);
+
+            assertNotNull(ctr);
+
+            assertEquals(SYS_METRICS + "." + ASSERTION_ERROR_CNT, ctr.name());
+
+            assertEquals("Number of AssertionErrors thrown in this JVM.", ctr.description());
+        }
+        finally {
+            stopAllGrids();
+        }
+    }
+}

modules/core/src/test/java/org/apache/ignite/testsuites/IgniteKernalSelfTestSuite.java

@@ -60,6 +60,7 @@
 import org.apache.ignite.internal.processors.cluster.ClusterStateChangeOnNodeJoinTest;
 import org.apache.ignite.internal.processors.cluster.GridAddressResolverSelfTest;
 import org.apache.ignite.internal.processors.cluster.GridUpdateNotifierSelfTest;
+import org.apache.ignite.internal.processors.metric.GridMetricManagerAssertionMetricTest;
 import org.apache.ignite.internal.processors.port.GridPortProcessorSelfTest;
 import org.apache.ignite.internal.util.GridMutableLongTest;
 import org.apache.ignite.internal.util.GridStartupWithUndefinedIgniteHomeSelfTest;
@@ -113,6 +114,7 @@
     IgniteConnectionConcurrentReserveAndRemoveTest.class,
     LongJVMPauseDetectorTest.class,
     ClusterMetricsSelfTest.class,
+    GridMetricManagerAssertionMetricTest.class,
     DeploymentRequestOfUnknownClassProcessingTest.class,
     ThreadNameValidationTest.class,
     NodeWithFilterRestartTest.class,