content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.instrumentation.grpc.v1_6;
  
  import static io.opentelemetry.instrumentation.grpc.v1_6.CapturedGrpcMetadataUtil.lowercase;
  import static io.opentelemetry.instrumentation.grpc.v1_6.CapturedGrpcMetadataUtil.requestAttributeKey;
  
  import io.grpc.Status;
  import io.opentelemetry.api.common.AttributeKey;
  import io.opentelemetry.api.common.AttributesBuilder;
  import io.opentelemetry.context.Context;
  import io.opentelemetry.instrumentation.api.instrumenter.AttributesExtractor;
  import java.util.List;
  import javax.annotation.Nullable;
  
  final class GrpcAttributesExtractor implements AttributesExtractor<GrpcRequest, Status> {
  
    // copied from RpcIncubatingAttributes
    private static final AttributeKey<Long> RPC_GRPC_STATUS_CODE =
        AttributeKey.longKey("rpc.grpc.status_code");
  
    private final GrpcRpcAttributesGetter getter;
    private final List<String> capturedRequestMetadata;
  
    GrpcAttributesExtractor(
        GrpcRpcAttributesGetter getter, List<String> requestMetadataValuesToCapture) {
      this.getter = getter;
      this.capturedRequestMetadata = lowercase(requestMetadataValuesToCapture);
    }
  
    @Override
    public void onStart(AttributesBuilder attributes, Context parentContext, GrpcRequest request) {
      // Request attributes captured on request end.
    }
  
    @Override
    public void onEnd(
        AttributesBuilder attributes,
        Context context,
        GrpcRequest request,
        @Nullable Status status,
        @Nullable Throwable error) {
      if (status != null) {
        attributes.put(RPC_GRPC_STATUS_CODE, status.getCode().value());
      }
      for (String key : capturedRequestMetadata) {
        List<String> value = getter.metadataValue(request, key);
        if (!value.isEmpty()) {
          attributes.put(requestAttributeKey(key), value);
        }
      }
    }
  }
  