content: /*
   * 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.kafka.image.publisher.metrics;
  
  import org.apache.kafka.common.utils.MockTime;
  import org.apache.kafka.controller.metrics.ControllerMetricsTestUtils;
  
  import com.yammer.metrics.core.Gauge;
  import com.yammer.metrics.core.MetricName;
  import com.yammer.metrics.core.MetricsRegistry;
  
  import org.junit.jupiter.api.Test;
  import org.junit.jupiter.api.Timeout;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.HashSet;
  import java.util.List;
  import java.util.Optional;
  import java.util.Set;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  
  
  @Timeout(value = 40)
  public class SnapshotEmitterMetricsTest {
      private static final Logger log = LoggerFactory.getLogger(SnapshotEmitterMetricsTest.class);
  
      static class SnapshotEmitterMetricsTestContext implements AutoCloseable {
          final MetricsRegistry registry;
          final MockTime time;
          final SnapshotEmitterMetrics metrics;
  
          SnapshotEmitterMetricsTestContext() {
              this.registry = new MetricsRegistry();
              this.time = new MockTime(0, 10000L, 0L);
              this.metrics = new SnapshotEmitterMetrics(Optional.of(registry), time);
          }
  
          @SuppressWarnings("unchecked") // suppress warning about Gauge typecast
          long readLongGauge(String name) {
              MetricName metricName = new MetricName(
                  "kafka.server",
                  "SnapshotEmitter",
                  name,
                  null,
                  "kafka.server:type=SnapshotEmitter,name=" + name
              );
              return ((Gauge<Long>) registry.allMetrics().get(metricName)).value();
          }
  
          @Override
          public void close() {
              try {
                  registry.shutdown();
              } catch (Exception e) {
                  log.error("Error closing registry", e);
              }
          }
      }
  
      @Test
      public void testMetricNames() {
          try (SnapshotEmitterMetricsTestContext ctx = new SnapshotEmitterMetricsTestContext()) {
              ControllerMetricsTestUtils.assertMetricsForTypeEqual(ctx.registry, "kafka.server:",
                  new HashSet<>(List.of(
                      "kafka.server:type=SnapshotEmitter,name=LatestSnapshotGeneratedBytes",
                      "kafka.server:type=SnapshotEmitter,name=LatestSnapshotGeneratedAgeMs"
                  )));
              ctx.metrics.close();
              ControllerMetricsTestUtils.assertMetricsForTypeEqual(ctx.registry, "KafkaController",
                      Set.of());
          }
      }
  
      @Test
      public void testLatestSnapshotGeneratedBytesMetric() {
          try (SnapshotEmitterMetricsTestContext ctx = new SnapshotEmitterMetricsTestContext()) {
              assertEquals(0L, ctx.metrics.latestSnapshotGeneratedBytes());
              ctx.metrics.setLatestSnapshotGeneratedBytes(12345L);
              assertEquals(12345L, ctx.metrics.latestSnapshotGeneratedBytes());
              assertEquals(12345L, ctx.readLongGauge("LatestSnapshotGeneratedBytes"));
          }
      }
  
      @Test
      public void testLatestSnapshotGeneratedAgeMsMetric() {
          try (SnapshotEmitterMetricsTestContext ctx = new SnapshotEmitterMetricsTestContext()) {
              assertEquals(10000L, ctx.metrics.latestSnapshotGeneratedTimeMs());
              assertEquals(0L, ctx.metrics.latestSnapshotGeneratedAgeMs());
              ctx.time.sleep(20000L);
              assertEquals(10000L, ctx.metrics.latestSnapshotGeneratedTimeMs());
              assertEquals(20000L, ctx.metrics.latestSnapshotGeneratedAgeMs());
              assertEquals(20000L, ctx.readLongGauge("LatestSnapshotGeneratedAgeMs"));
          }
      }
  }
  