import quincy 17.2.0

[ceph.git] / ceph / src / arrow / cpp / src / arrow / csv / column_decoder.h

diff --git a/ceph/src/arrow/cpp/src/arrow/csv/column_decoder.h b/ceph/src/arrow/cpp/src/arrow/csv/column_decoder.h
new file mode 100644 (file)
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+++ b/ceph/src/arrow/cpp/src/arrow/csv/column_decoder.h
@@ -0,0 +1,64 @@
+// 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 <utility>
+
+#include "arrow/result.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/type_fwd.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace csv {
+
+class BlockParser;
+struct ConvertOptions;
+
+class ARROW_EXPORT ColumnDecoder {
+ public:
+  virtual ~ColumnDecoder() = default;
+
+  /// Spawn a task that will try to convert and insert the given CSV block
+  virtual Future<std::shared_ptr<Array>> Decode(
+      const std::shared_ptr<BlockParser>& parser) = 0;
+
+  /// Construct a strictly-typed ColumnDecoder.
+  static Result<std::shared_ptr<ColumnDecoder>> Make(MemoryPool* pool,
+                                                     std::shared_ptr<DataType> type,
+                                                     int32_t col_index,
+                                                     const ConvertOptions& options);
+
+  /// Construct a type-inferring ColumnDecoder.
+  /// Inference will run only on the first block, the type will be frozen afterwards.
+  static Result<std::shared_ptr<ColumnDecoder>> Make(MemoryPool* pool, int32_t col_index,
+                                                     const ConvertOptions& options);
+
+  /// Construct a ColumnDecoder for a column of nulls
+  /// (i.e. not present in the CSV file).
+  static Result<std::shared_ptr<ColumnDecoder>> MakeNull(MemoryPool* pool,
+                                                         std::shared_ptr<DataType> type);
+
+ protected:
+  ColumnDecoder() = default;
+};
+
+}  // namespace csv
+}  // namespace arrow