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 com.datastax.oss.driver.internal.core.metrics;
  
  import com.datastax.oss.driver.api.core.config.DefaultDriverOption;
  import com.datastax.oss.driver.api.core.context.DriverContext;
  import com.datastax.oss.driver.api.core.metadata.Node;
  import com.datastax.oss.driver.api.core.metrics.NodeMetric;
  import com.datastax.oss.driver.api.core.metrics.SessionMetric;
  import com.datastax.oss.driver.shaded.guava.common.collect.ImmutableMap;
  import edu.umd.cs.findbugs.annotations.NonNull;
  import java.util.Objects;
  
  /**
   * A {@link MetricIdGenerator} that generates metric identifiers using a combination of names and
   * tags.
   *
   * <p>Session metric identifiers contain a name starting with "session." and ending with the metric
   * path, and a tag with the key "session" and the value of the current session name.
   *
   * <p>Node metric identifiers contain a name starting with "nodes." and ending with the metric path,
   * and two tags: one with the key "session" and the value of the current session name, the other
   * with the key "node" and the value of the current node endpoint.
   */
  public class TaggingMetricIdGenerator implements MetricIdGenerator {
  
    private final String sessionName;
    private final String sessionPrefix;
    private final String nodePrefix;
  
    @SuppressWarnings("unused")
    public TaggingMetricIdGenerator(DriverContext context) {
      sessionName = context.getSessionName();
      String prefix =
          Objects.requireNonNull(
              context
                  .getConfig()
                  .getDefaultProfile()
                  .getString(DefaultDriverOption.METRICS_ID_GENERATOR_PREFIX, ""));
      sessionPrefix = prefix.isEmpty() ? "session." : prefix + ".session.";
      nodePrefix = prefix.isEmpty() ? "nodes." : prefix + ".nodes.";
    }
  
    @NonNull
    @Override
    public MetricId sessionMetricId(@NonNull SessionMetric metric) {
      return new DefaultMetricId(
          sessionPrefix + metric.getPath(), ImmutableMap.of("session", sessionName));
    }
  
    @NonNull
    @Override
    public MetricId nodeMetricId(@NonNull Node node, @NonNull NodeMetric metric) {
      return new DefaultMetricId(
          nodePrefix + metric.getPath(),
          ImmutableMap.of("session", sessionName, "node", node.getEndPoint().toString()));
    }
  }
  