metadata_scan.h

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/*
 * 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 <cstdint>
#include <memory>
#include <optional>
#include <string>
#include <vector>
 
#include "iceberg/arrow_c_data.h"
#include "iceberg/iceberg_export.h"
#include "iceberg/result.h"
#include "iceberg/type_fwd.h"
#include "iceberg/util/error_collector.h"
#include "iceberg/util/stream.h"
 
namespace iceberg {
 
using MetadataScanTaskStream = Stream<std::shared_ptr<MetadataScanTask>>;
using MetadataScanTaskStreamPtr = std::unique_ptr<MetadataScanTaskStream>;
 
namespace internal {
 
struct MetadataScanContext {
  MetadataTableKind kind;
  std::shared_ptr<const TableMetadata> table_metadata;
  std::shared_ptr<Schema> schema;
  std::shared_ptr<Schema> projected_schema;
  bool case_sensitive = true;
  std::optional<int64_t> snapshot_id;
  std::string ref_name;
  std::optional<int64_t> as_of_time_in_millis;
};
 
}  // namespace internal
 
class ICEBERG_EXPORT MetadataScanBuilder : public ErrorCollector {
 public:
  ~MetadataScanBuilder() override;
 
  static Result<std::unique_ptr<MetadataScanBuilder>> Make(const MetadataTable& table);
 
  MetadataScanBuilder& Select(const std::vector<std::string>& columns);
 
  MetadataScanBuilder& Project(std::shared_ptr<Schema> schema);
 
  MetadataScanBuilder& CaseSensitive(bool value);
 
  MetadataScanBuilder& UseSnapshot(int64_t snapshot_id);
 
  MetadataScanBuilder& UseRef(const std::string& ref);
 
  MetadataScanBuilder& AsOfTime(int64_t as_of_time_in_millis);
 
  Result<std::unique_ptr<MetadataScan>> Build();
 
 private:
  explicit MetadataScanBuilder(const MetadataTable& table);
 
  const MetadataTable* table_;
  internal::MetadataScanContext context_;
};
 
class ICEBERG_EXPORT MetadataScan {
 public:
  virtual ~MetadataScan();
 
  virtual Result<MetadataScanTaskStreamPtr> PlanTasksStream() const = 0;
 
  virtual Result<std::vector<std::shared_ptr<MetadataScanTask>>> PlanTasks() const;
 
  virtual Result<ArrowArrayStream> ToArrowArrayStream() const;
 
 protected:
  explicit MetadataScan(internal::MetadataScanContext context);
 
  const internal::MetadataScanContext& context() const { return context_; }
 
 private:
  const internal::MetadataScanContext context_;
};
 
}  // namespace iceberg