ZOOKEEPER-5036: Add Timeline Metrics Provider for external metrics collection systems - Unit tests and configs

Author: himanshumaurya09876

bin/zkEnv.sh

@@ -113,6 +113,11 @@ for d in "$ZOOBINDIR"/../zookeeper-metrics-providers/zookeeper-prometheus-metric
   CLASSPATH="$d:$CLASSPATH"
 done
 
+#make it work for developers
+for d in "$ZOOBINDIR"/../zookeeper-metrics-providers/zookeeper-timeline-metrics/target/lib/*.jar; do
+  CLASSPATH="$d:$CLASSPATH"
+done
+
 #make it work for developers
 CLASSPATH="$ZOOBINDIR/../build/classes:$CLASSPATH"
 
@@ -122,6 +127,9 @@ CLASSPATH="$ZOOBINDIR/../zookeeper-server/target/classes:$CLASSPATH"
 #make it work for developers
 CLASSPATH="$ZOOBINDIR/../zookeeper-metrics-providers/zookeeper-prometheus-metrics/target/classes:$CLASSPATH"
 
+#make it work for developers
+CLASSPATH="$ZOOBINDIR/../zookeeper-metrics-providers/zookeeper-timeline-metrics/target/classes:$CLASSPATH"
+
 case "$(uname)" in
   CYGWIN* | MINGW*) cygwin=true ;;
   *) cygwin=false ;;

zookeeper-metrics-providers/zookeeper-timeline-metrics/pom.xml

@@ -23,7 +23,7 @@
   <parent>
     <groupId>org.apache.zookeeper</groupId>
     <artifactId>zookeeper-metrics-providers</artifactId>
-    <version>3.9.3</version>
+    <version>3.10.0-SNAPSHOT</version>
   </parent>
 
   <artifactId>zookeeper-timeline-metrics</artifactId>
@@ -47,7 +47,14 @@
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>
     </dependency>
-    
+
+    <!-- Dropwizard Metrics - needed for AvgMinMaxPercentileCounter -->
+    <dependency>
+      <groupId>io.dropwizard.metrics</groupId>
+      <artifactId>metrics-core</artifactId>
+      <scope>test</scope>
+    </dependency>
+
     <!-- Test dependencies -->
     <dependency>
       <groupId>org.mockito</groupId>

zookeeper-metrics-providers/zookeeper-timeline-metrics/src/main/java/org/apache/zookeeper/metrics/timeline/MetricSnapshot.java

@@ -143,7 +143,7 @@ public String getAppId() {
     /**
      * Returns all counter metrics in this snapshot.
      * 
-     * @return an unmodifiable view of the counters map
+     * @return a view of the counters map
      */
     public Map<String, Long> getCounters() {
         return counters;
@@ -152,7 +152,7 @@ public Map<String, Long> getCounters() {
     /**
      * Returns all gauge metrics in this snapshot.
      * 
-     * @return an unmodifiable view of the gauges map
+     * @return a view of the gauges map
      */
     public Map<String, Double> getGauges() {
         return gauges;
@@ -161,7 +161,7 @@ public Map<String, Double> getGauges() {
     /**
      * Returns all summary metrics in this snapshot.
      * 
-     * @return an unmodifiable view of the summaries map
+     * @return a view of the summaries map
      */
     public Map<String, Double> getSummaries() {
         return summaries;

zookeeper-metrics-providers/zookeeper-timeline-metrics/src/test/java/org/apache/zookeeper/metrics/timeline/MockTimelineMetricsSink.java

@@ -0,0 +1,134 @@
+/*
+ * 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.zookeeper.metrics.timeline;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Properties;
+
+/**
+ * Mock implementation of TimelineMetricsSink for testing purposes.
+ *
+ * <p>This mock captures all snapshots sent to it and provides methods
+ * to verify the snapshots in tests.</p>
+ */
+public class MockTimelineMetricsSink implements TimelineMetricsSink {
+
+    private final List<MetricSnapshot> snapshots = new ArrayList<>();
+    private Properties configuration;
+    private boolean configured = false;
+    private boolean closed = false;
+    private volatile boolean throwOnSend = false;
+    private volatile boolean throwOnConfigure = false;
+
+    @Override
+    public void configure(Properties configuration) throws Exception {
+        if (throwOnConfigure) {
+            throw new Exception("Mock configuration failure");
+        }
+        this.configuration = configuration;
+        this.configured = true;
+    }
+
+    @Override
+    public void send(MetricSnapshot snapshot) throws Exception {
+        if (throwOnSend) {
+            throw new Exception("Mock send failure");
+        }
+        synchronized (snapshots) {
+            snapshots.add(snapshot);
+        }
+    }
+
+    @Override
+    public void close() throws Exception {
+        this.closed = true;
+    }
+
+    /**
+     * Returns all captured snapshots.
+     */
+    public List<MetricSnapshot> getSnapshots() {
+        synchronized (snapshots) {
+            return new ArrayList<>(snapshots);
+        }
+    }
+
+    /**
+     * Returns the last captured snapshot, or null if none.
+     */
+    public MetricSnapshot getLastSnapshot() {
+        synchronized (snapshots) {
+            return snapshots.isEmpty() ? null : snapshots.get(snapshots.size() - 1);
+        }
+    }
+
+    /**
+     * Returns the number of snapshots captured.
+     */
+    public int getSnapshotCount() {
+        synchronized (snapshots) {
+            return snapshots.size();
+        }
+    }
+
+    /**
+     * Clears all captured snapshots.
+     */
+    public void clearSnapshots() {
+        synchronized (snapshots) {
+            snapshots.clear();
+        }
+    }
+
+    /**
+     * Returns the configuration passed to configure().
+     */
+    public Properties getConfiguration() {
+        return configuration;
+    }
+
+    /**
+     * Returns whether configure() was called.
+     */
+    public boolean isConfigured() {
+        return configured;
+    }
+
+    /**
+     * Returns whether close() was called.
+     */
+    public boolean isClosed() {
+        return closed;
+    }
+
+    /**
+     * Sets whether send() should throw an exception.
+     */
+    public void setThrowOnSend(boolean throwOnSend) {
+        this.throwOnSend = throwOnSend;
+    }
+
+    /**
+     * Sets whether configure() should throw an exception.
+     */
+    public void setThrowOnConfigure(boolean throwOnConfigure) {
+        this.throwOnConfigure = throwOnConfigure;
+    }
+}