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.beam.runners.samza.metrics;
  
  import java.io.Closeable;
  import org.apache.beam.sdk.metrics.MetricsEnvironment;
  
  /** This class wraps a {@link java.util.function.Supplier} function call with BEAM metrics. */
  public class FnWithMetricsWrapper {
  
    /** Interface for functions to be wrapped with metrics. */
    public interface SupplierWithException<T> {
      T get() throws Exception;
    }
  
    private final SamzaMetricsContainer metricsContainer;
    private final String stepName;
  
    public FnWithMetricsWrapper(SamzaMetricsContainer metricsContainer, String stepName) {
      this.metricsContainer = metricsContainer;
      this.stepName = stepName;
    }
  
    public <T> T wrap(SupplierWithException<T> fn, boolean shouldUpdateMetrics) throws Exception {
      try (Closeable closeable =
          MetricsEnvironment.scopedMetricsContainer(metricsContainer.getContainer(stepName))) {
        T result = fn.get();
        // Skip updating metrics if not necessary to improve performance
        if (shouldUpdateMetrics) {
          metricsContainer.updateMetrics(stepName);
        }
        return result;
      }
    }
  }
  