avro_direct_decoder_internal.h

/*
 * 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.
 */
 
#pragma once
 
#include <arrow/array/builder_base.h>
#include <avro/Decoder.hh>
#include <avro/Node.hh>
 
#include "iceberg/arrow/metadata_column_util_internal.h"
#include "iceberg/result.h"
#include "iceberg/schema.h"
#include "iceberg/schema_util.h"
 
namespace iceberg::avro {
 
struct DecodeContext {
  // Scratch buffer for string decoding (reused across rows)
  std::string string_scratch;
  // Scratch buffer for binary/fixed/uuid/decimal data (reused across rows)
  std::vector<uint8_t> bytes_scratch;
  // Cache for avro field index to projection index mapping
  // Key: pointer to projections array (identifies struct schema)
  // Value: vector mapping avro field index -> projection index (-1 if not projected)
  std::unordered_map<const FieldProjection*, std::vector<int>> avro_to_projection_cache;
};
 
Status DecodeAvroToBuilder(const ::avro::NodePtr& avro_node, ::avro::Decoder& decoder,
                           const SchemaProjection& projection,
                           const Schema& projected_schema,
                           const arrow::MetadataColumnContext& metadata_context,
                           ::arrow::ArrayBuilder* array_builder, DecodeContext& ctx);
 
}  // namespace iceberg::avro