APPSERV-11 Adds Health Check Alerts to Monitoring Console

appserver/monitoring-console/core/src/main/java/fish/payara/monitoring/alert/Alert.java

@@ -0,0 +1,285 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright (c) 2020 Payara Foundation and/or its affiliates. All rights reserved.
+ *
+ * The contents of this file are subject to the terms of either the GNU
+ * General Public License Version 2 only ("GPL") or the Common Development
+ * and Distribution License("CDDL") (collectively, the "License").  You
+ * may not use this file except in compliance with the License.  You can
+ * obtain a copy of the License at
+ * https://github.com/payara/Payara/blob/master/LICENSE.txt
+ * See the License for the specific
+ * language governing permissions and limitations under the License.
+ *
+ * When distributing the software, include this License Header Notice in each
+ * file and include the License file at glassfish/legal/LICENSE.txt.
+ *
+ * GPL Classpath Exception:
+ * The Payara Foundation designates this particular file as subject to the "Classpath"
+ * exception as provided by the Payara Foundation in the GPL Version 2 section of the License
+ * file that accompanied this code.
+ *
+ * Modifications:
+ * If applicable, add the following below the License Header, with the fields
+ * enclosed by brackets [] replaced by your own identifying information:
+ * "Portions Copyright [year] [name of copyright owner]"
+ *
+ * Contributor(s):
+ * If you wish your version of this file to be governed by only the CDDL or
+ * only the GPL Version 2, indicate your decision by adding "[Contributor]
+ * elects to include this software in this distribution under the [CDDL or GPL
+ * Version 2] license."  If you don't indicate a single choice of license, a
+ * recipient has the option to distribute your version of this file under
+ * either the CDDL, the GPL Version 2 or to extend the choice of license to
+ * its licensees as provided above.  However, if you add GPL Version 2 code
+ * and therefore, elected the GPL Version 2 license, then the option applies
+ * only if the new code is made subject to such option by the copyright
+ * holder.
+ */
+package fish.payara.monitoring.alert;
+
+import static java.time.Instant.ofEpochMilli;
+import static java.time.LocalDateTime.ofInstant;
+import static java.time.ZoneId.systemDefault;
+
+import java.time.format.DateTimeFormatter;
+import java.util.Iterator;
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import fish.payara.monitoring.model.Series;
+import fish.payara.monitoring.model.SeriesDataset;
+
+/**
+ * An {@linkplain Alert} is raised when a watched series matches the {@link Circumstance}s for {@link Level#RED} or
+ * {@link Level#AMBER} and last until the same {@link Series} and instance transitions to {@link Level#GREEN} or
+ * {@link Level#WHITE}.
+ * 
+ * @see Watch
+ * 
+ * @author Jan Bernitt
+ */
+public final class Alert implements Iterable<Alert.Frame> {
+
+    public enum Level {
+        /**
+         * Critical level
+         */
+        RED,
+        /**
+         * Elevated level to warn about
+         */
+        AMBER,
+        /**
+         * Within expected range
+         */
+        GREEN,
+        /**
+         * Not classified
+         */
+        WHITE;
+
+        public boolean isLessSevereThan(Level other) {
+            return ordinal() > other.ordinal();
+        }
+    }
+
+    public static final class Frame implements Iterable<SeriesDataset> {
+        public final Level level;
+        public final SeriesDataset cause;
+        public final long start;
+        private final List<SeriesDataset> captured;
+        long end;
+
+        public Frame(Level level, SeriesDataset cause, List<SeriesDataset> captured) {
+            this.level = level;
+            this.cause = cause;
+            this.captured = captured;
+            this.start = System.currentTimeMillis();
+        }
+
+        @Override
+        public Iterator<SeriesDataset> iterator() {
+            return captured.iterator();
+        }
+
+        public long getEnd() {
+            return end;
+        }
+    }
+
+    private static final AtomicInteger NEXT_SERIAL = new AtomicInteger();
+    /**
+     * The change count tracks state changes of all {@link Alert} instances.
+     */
+    private static final AtomicInteger CHANGE_COUNT = new AtomicInteger();
+
+    public static int getChangeCount() {
+        return CHANGE_COUNT.get();
+    }
+
+    public final int serial;
+    public final Watch initiator;
+    private final List<Frame> frames = new CopyOnWriteArrayList<>();
+    /**
+     * The current state of the alert.
+     */
+    private Level level = Level.WHITE;
+    private boolean acknowledged;
+
+    public Alert(Watch initiator) {
+        this.initiator = initiator;
+        this.serial = NEXT_SERIAL.incrementAndGet();
+    }
+
+    @Override
+    public Iterator<Frame> iterator() {
+        return frames.iterator();
+    }
+
+    public Alert addTransition(Level to, SeriesDataset cause, List<SeriesDataset> captured) {
+        assertRedOrAmberLevel(to);
+        if (!isStopped()) {
+            if (!frames.isEmpty()) {
+                Frame recent = getEndFrame();
+                assertSameSeriesAndInstance(cause, recent.cause);
+                recent.end = System.currentTimeMillis();
+                acknowledged = acknowledged && to.isLessSevereThan(recent.level);
+            } else {
+                assertMatchesWachtedSeries(cause);
+                acknowledged = false;
+            }
+            frames.add(new Frame(to, cause, captured));
+            CHANGE_COUNT.incrementAndGet();
+            level = to;
+        }
+        return this;
+    }
+
+    public boolean isStarted() {
+        return !frames.isEmpty();
+    }
+
+    public boolean isAcknowledged() {
+        return acknowledged;
+    }
+
+    public void acknowledge() {
+        if (!isAcknowledged()) {
+            acknowledged = true;
+            CHANGE_COUNT.incrementAndGet();
+        }
+    }
+
+    public boolean isStopped() {
+        return level.isLessSevereThan(Level.AMBER) && !frames.isEmpty();
+    }
+
+    public void stop(Level to) {
+        if (!isStopped()) {
+            assertGreenOrWhiteLevel(to);
+            this.level = to;
+            getEndFrame().end = System.currentTimeMillis();
+            CHANGE_COUNT.incrementAndGet();
+        }
+    }
+
+    public Level getLevel() {
+        return level;
+    }
+
+    public long getStartTime() {
+        return frames.isEmpty() ? -1L : frames.get(0).start;
+    }
+
+    public long getEndTime() {
+        return frames.isEmpty() ? -1L : getEndFrame().end;
+    }
+
+    public Series getSeries() {
+        return getEndFrame().cause.getSeries();
+    }
+
+    public String getInstance() {
+        return getEndFrame().cause.getInstance();
+    }
+
+    public Frame getEndFrame() {
+        return frames.get(frames.size() - 1);
+    }
+
+    @Override
+    public int hashCode() {
+        return serial;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        return obj instanceof Alert && equalTo((Alert) obj);
+    }
+
+    public boolean equalTo(Alert other) {
+        return serial == other.serial;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder str = new StringBuilder();
+        str.append('(').append(serial).append(") ").append(initiator.name);
+        long startTime = getStartTime();
+        str.append('[');
+        if (startTime >= 0) {
+            str.append(formatTime(startTime));
+        }
+        str.append('-');
+        long endTime = getEndTime();
+        if (endTime >= 0) {
+            str.append(formatTime(endTime));
+        }
+        if (isAcknowledged()) {
+            str.append(" ACK");
+        }
+        str.append(']');
+        str.append(' ');
+        for (int i = 0; i < frames.size(); i++) {
+            if (i > 0) {
+                str.append(" => ");
+            }
+            str.append(frames.get(i).level);
+        }
+        return str.toString();
+    }
+
+    private static final DateTimeFormatter TIME_FORMATTER = DateTimeFormatter.ISO_TIME;
+
+    private static String formatTime(long epochMillis) {
+        return TIME_FORMATTER.format(ofInstant(ofEpochMilli(epochMillis), systemDefault()));
+    }
+
+    private static void assertRedOrAmberLevel(Level to) {
+        if (to != Level.RED && to != Level.AMBER) {
+            throw new IllegalArgumentException("Alerts only transtion between RED and AMBER levels but got: " + to);
+        }
+    }
+
+    private void assertMatchesWachtedSeries(SeriesDataset cause) {
+        if (!initiator.watched.series.matches(cause.getSeries())) {
+            throw new IllegalArgumentException("Cause did not match with watched series: " + cause.getSeries());
+        }
+    }
+
+    private static void assertSameSeriesAndInstance(SeriesDataset a, SeriesDataset b) {
+        if (!b.getSeries().equalTo(a.getSeries()) || !b.getInstance().equals(a.getInstance())) {
+            throw new IllegalArgumentException(
+                    "All transitions for an alert must refer to same cause series and instance but got: " + a);
+        }
+    }
+
+    private static void assertGreenOrWhiteLevel(Level to) {
+        if (to != Level.GREEN && to != Level.WHITE) {
+            throw new IllegalArgumentException("Alerts only end on GREEN or WHITE levels but got: " + to);
+        }
+    }
+}

appserver/monitoring-console/core/src/main/java/fish/payara/monitoring/alert/AlertService.java

@@ -0,0 +1,113 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright (c) 2020 Payara Foundation and/or its affiliates. All rights reserved.
+ *
+ * The contents of this file are subject to the terms of either the GNU
+ * General Public License Version 2 only ("GPL") or the Common Development
+ * and Distribution License("CDDL") (collectively, the "License").  You
+ * may not use this file except in compliance with the License.  You can
+ * obtain a copy of the License at
+ * https://github.com/payara/Payara/blob/master/LICENSE.txt
+ * See the License for the specific
+ * language governing permissions and limitations under the License.
+ *
+ * When distributing the software, include this License Header Notice in each
+ * file and include the License file at glassfish/legal/LICENSE.txt.
+ *
+ * GPL Classpath Exception:
+ * The Payara Foundation designates this particular file as subject to the "Classpath"
+ * exception as provided by the Payara Foundation in the GPL Version 2 section of the License
+ * file that accompanied this code.
+ *
+ * Modifications:
+ * If applicable, add the following below the License Header, with the fields
+ * enclosed by brackets [] replaced by your own identifying information:
+ * "Portions Copyright [year] [name of copyright owner]"
+ *
+ * Contributor(s):
+ * If you wish your version of this file to be governed by only the CDDL or
+ * only the GPL Version 2, indicate your decision by adding "[Contributor]
+ * elects to include this software in this distribution under the [CDDL or GPL
+ * Version 2] license."  If you don't indicate a single choice of license, a
+ * recipient has the option to distribute your version of this file under
+ * either the CDDL, the GPL Version 2 or to extend the choice of license to
+ * its licensees as provided above.  However, if you add GPL Version 2 code
+ * and therefore, elected the GPL Version 2 license, then the option applies
+ * only if the new code is made subject to such option by the copyright
+ * holder.
+ */
+package fish.payara.monitoring.alert;
+
+import java.util.Collection;
+import java.util.function.Predicate;
+
+import org.jvnet.hk2.annotations.Contract;
+
+import fish.payara.monitoring.model.Series;
+
+/**
+ * The {@link AlertService} manages and evaluates {@link Watch}s that cause {@link Alert}s.
+ *
+ * @author Jan Bernitt
+ */
+@Contract
+public interface AlertService {
+
+    /*
+     * Alerts
+     */
+
+    class AlertStatistics {
+        /**
+         * Can be used by (asynchronous) consumers to determine if they have seen the most recent state of alerts. If
+         * the change count is still the same they have processed already there is nothing new to process.
+         */
+        public int changeCount;
+        public int unacknowledgedRedAlerts;
+        public int acknowledgedRedAlerts;
+        public int unacknowledgedAmberAlerts;
+        public int acknowledgedAmberAlerts;
+        public int watches;
+    }
+
+    AlertStatistics getAlertStatistics();
+
+    Collection<Alert> alertsMatching(Predicate<Alert> filter);
+
+    default Alert alertBySerial(int serial) {
+        Collection<Alert> matches = alertsMatching(alert -> alert.serial == serial);
+        return matches.isEmpty() ? null : matches.iterator().next();
+    }
+
+    default Collection<Alert> alertsFor(Series series) {
+        return alertsMatching(alert -> alert.getSeries().equalTo(series));
+    }
+
+    default Collection<Alert> alerts() {
+        return alertsMatching(alert -> true);
+    }
+
+    /*
+     * Watches
+     */
+
+    /**
+     * Adds a watch to the evaluation loop. To remove the watch just use {@link Watch#stop()}.
+     *
+     * @param watch new watch to add to evaluation loop
+     */
+    void addWatch(Watch watch);
+
+    /**
+     * @return All watches registered for evaluation.
+     */
+    Collection<Watch> watches();
+
+    /**
+     * @param series a simple or pattern {@link Series}, not null
+     * @return All watches matching the given {@link Series}. {@link Series#ANY} will match all watches similar to
+     *         {@link #watches()}.
+     */
+    Collection<Watch> wachtesFor(Series series);
+}