arrow/json/object_parser.h

0001 // Licensed to the Apache Software Foundation (ASF) under one
0002 // or more contributor license agreements.  See the NOTICE file
0003 // distributed with this work for additional information
0004 // regarding copyright ownership.  The ASF licenses this file
0005 // to you under the Apache License, Version 2.0 (the
0006 // "License"); you may not use this file except in compliance
0007 // with the License.  You may obtain a copy of the License at
0008 //
0009 //   http://www.apache.org/licenses/LICENSE-2.0
0010 //
0011 // Unless required by applicable law or agreed to in writing,
0012 // software distributed under the License is distributed on an
0013 // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
0014 // KIND, either express or implied.  See the License for the
0015 // specific language governing permissions and limitations
0016 // under the License.
0017
0018 #pragma once
0019
0020 #include <memory>
0021 #include <string_view>
0022 #include <unordered_map>
0023
0024 #include "arrow/result.h"
0025 #include "arrow/util/visibility.h"
0026
0027 namespace arrow {
0028 namespace json {
0029 namespace internal {
0030
0031 /// This class is a helper to parse a json object from a string.
0032 /// It uses rapidjson::Document in implementation.
0033 class ARROW_EXPORT ObjectParser {
0034  public:
0035   ObjectParser();
0036   ~ObjectParser();
0037
0038   Status Parse(std::string_view json);
0039
0040   Result<std::string> GetString(const char* key) const;
0041
0042   Result<bool> GetBool(const char* key) const;
0043
0044   // Get all members of the object as a map from string keys to string values
0045   Result<std::unordered_map<std::string, std::string>> GetStringMap() const;
0046
0047  private:
0048   class Impl;
0049   std::unique_ptr<Impl> impl_;
0050 };
0051
0052 }  // namespace internal
0053 }  // namespace json
0054 }  // namespace arrow