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.cassandra.sidecar.metrics.server;
  
  import java.util.Objects;
  import java.util.function.Function;
  
  import com.codahale.metrics.DefaultSettableGauge;
  import com.codahale.metrics.Metric;
  import com.codahale.metrics.MetricRegistry;
  import com.codahale.metrics.Timer;
  import org.apache.cassandra.sidecar.metrics.DeltaGauge;
  import org.apache.cassandra.sidecar.metrics.NamedMetric;
  
  import static org.apache.cassandra.sidecar.metrics.server.ServerMetrics.SERVER_PREFIX;
  
  /**
   * Tracks metrics related to restore functionality provided by Sidecar.
   */
  public class RestoreMetrics
  {
      public static final String DOMAIN = SERVER_PREFIX + ".Restore";
      protected final MetricRegistry metricRegistry;
      public final NamedMetric<Timer> sliceReplicationTime;
      public final NamedMetric<Timer> jobCompletionTime;
      public final NamedMetric<Timer> consistencyCheckTime;
      public final NamedMetric<DeltaGauge> successfulJobs;
      public final NamedMetric<DeltaGauge> failedJobs;
      public final NamedMetric<DefaultSettableGauge<Integer>> activeJobs;
      public final NamedMetric<DeltaGauge> tokenRefreshed;
      public final NamedMetric<DeltaGauge> tokenUnauthorized;
      public final NamedMetric<DeltaGauge> tokenExpired;
      public final NamedMetric<DefaultSettableGauge<Integer>> activeTasks;
  
      public RestoreMetrics(MetricRegistry metricRegistry)
      {
          this.metricRegistry = Objects.requireNonNull(metricRegistry, "Metric registry can not be null");
  
          sliceReplicationTime = createMetric("SliceReplicationTime", metricRegistry::timer);
          jobCompletionTime = createMetric("JobCompletionTime", metricRegistry::timer);
          consistencyCheckTime = createMetric("ConsistencyCheckTime", metricRegistry::timer);
          successfulJobs = createMetric("SuccessfulJobs", name -> metricRegistry.gauge(name, DeltaGauge::new));
          failedJobs = createMetric("FailedJobs", name -> metricRegistry.gauge(name, DeltaGauge::new));
          activeJobs = createMetric("ActiveJobs", name -> metricRegistry.gauge(name, () -> new DefaultSettableGauge<>(0)));
          tokenRefreshed = createMetric("TokenRefreshed", name -> metricRegistry.gauge(name, DeltaGauge::new));
          tokenUnauthorized = createMetric("TokenUnauthorized", name -> metricRegistry.gauge(name, DeltaGauge::new));
          tokenExpired = createMetric("TokenExpired",  name -> metricRegistry.gauge(name, DeltaGauge::new));
          activeTasks = createMetric("ActiveTasks", name -> metricRegistry.gauge(name, () -> new DefaultSettableGauge<>(0)));
      }
  
      private <T extends Metric> NamedMetric<T> createMetric(String simpleName, Function<String, T> metricCreator)
      {
          return NamedMetric.builder(metricCreator)
                            .withDomain(DOMAIN)
                            .withName(simpleName)
                            .build();
      }
  }
  