| // 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. |
| |
| #ifndef PARQUET_FILE_WRITER_H |
| #define PARQUET_FILE_WRITER_H |
| |
| #include <cstdint> |
| #include <memory> |
| |
| #include "parquet/column/properties.h" |
| #include "parquet/schema.h" |
| #include "parquet/util/memory.h" |
| #include "parquet/util/visibility.h" |
| |
| namespace parquet { |
| |
| class ColumnWriter; |
| class PageWriter; |
| class OutputStream; |
| |
| class PARQUET_EXPORT RowGroupWriter { |
| public: |
| // Forward declare a virtual class 'Contents' to aid dependency injection and more |
| // easily create test fixtures |
| // An implementation of the Contents class is defined in the .cc file |
| struct Contents { |
| virtual ~Contents() = default; |
| virtual int num_columns() const = 0; |
| virtual int64_t num_rows() const = 0; |
| |
| virtual ColumnWriter* NextColumn() = 0; |
| virtual int current_column() const = 0; |
| virtual void Close() = 0; |
| }; |
| |
| explicit RowGroupWriter(std::unique_ptr<Contents> contents); |
| |
| /** |
| * Construct a ColumnWriter for the indicated row group-relative column. |
| * |
| * Ownership is solely within the RowGroupWriter. The ColumnWriter is only valid |
| * until the next call to NextColumn or Close. As the contents are directly written to |
| * the sink, once a new column is started, the contents of the previous one cannot be |
| * modified anymore. |
| */ |
| ColumnWriter* NextColumn(); |
| /// Index of currently written column |
| int current_column(); |
| void Close(); |
| |
| int num_columns() const; |
| |
| /** |
| * Number of rows that shall be written as part of this RowGroup. |
| */ |
| int64_t num_rows() const; |
| |
| private: |
| // Holds a pointer to an instance of Contents implementation |
| std::unique_ptr<Contents> contents_; |
| }; |
| |
| class PARQUET_EXPORT ParquetFileWriter { |
| public: |
| // Forward declare a virtual class 'Contents' to aid dependency injection and more |
| // easily create test fixtures |
| // An implementation of the Contents class is defined in the .cc file |
| struct Contents { |
| virtual ~Contents() {} |
| // Perform any cleanup associated with the file contents |
| virtual void Close() = 0; |
| |
| virtual RowGroupWriter* AppendRowGroup(int64_t num_rows) = 0; |
| |
| virtual int64_t num_rows() const = 0; |
| virtual int num_columns() const = 0; |
| virtual int num_row_groups() const = 0; |
| |
| virtual const std::shared_ptr<WriterProperties>& properties() const = 0; |
| |
| // Return const-pointer to make it clear that this object is not to be copied |
| const SchemaDescriptor* schema() const { return &schema_; } |
| SchemaDescriptor schema_; |
| }; |
| |
| ParquetFileWriter(); |
| ~ParquetFileWriter(); |
| |
| static std::unique_ptr<ParquetFileWriter> Open( |
| const std::shared_ptr<::arrow::io::OutputStream>& sink, |
| const std::shared_ptr<schema::GroupNode>& schema, |
| const std::shared_ptr<WriterProperties>& properties = default_writer_properties()); |
| |
| static std::unique_ptr<ParquetFileWriter> Open( |
| const std::shared_ptr<OutputStream>& sink, |
| const std::shared_ptr<schema::GroupNode>& schema, |
| const std::shared_ptr<WriterProperties>& properties = default_writer_properties()); |
| |
| void Open(std::unique_ptr<Contents> contents); |
| void Close(); |
| |
| /** |
| * Construct a RowGroupWriter for the indicated number of rows. |
| * |
| * Ownership is solely within the ParquetFileWriter. The RowGroupWriter is only valid |
| * until the next call to AppendRowGroup or Close. |
| * |
| * @param num_rows The number of rows that are stored in the new RowGroup |
| */ |
| RowGroupWriter* AppendRowGroup(int64_t num_rows); |
| |
| /** |
| * Number of columns. |
| * |
| * This number is fixed during the lifetime of the writer as it is determined via |
| * the schema. |
| */ |
| int num_columns() const; |
| |
| /** |
| * Number of rows in the yet started RowGroups. |
| * |
| * Changes on the addition of a new RowGroup. |
| */ |
| int64_t num_rows() const; |
| |
| /** |
| * Number of started RowGroups. |
| */ |
| int num_row_groups() const; |
| |
| /** |
| * Configuration passed to the writer, e.g. the used Parquet format version. |
| */ |
| const std::shared_ptr<WriterProperties>& properties() const; |
| |
| /** |
| * Returns the file schema descriptor |
| */ |
| const SchemaDescriptor* schema() const; |
| |
| /** |
| * Returns a column descriptor in schema |
| */ |
| const ColumnDescriptor* descr(int i) const; |
| |
| private: |
| // Holds a pointer to an instance of Contents implementation |
| std::unique_ptr<Contents> contents_; |
| }; |
| |
| } // namespace parquet |
| |
| #endif // PARQUET_FILE_WRITER_H |