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cpl_json.h
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1 /******************************************************************************
2  * Project: Common Portability Library
3  * Purpose: Function wrapper for libjson-c access.
4  * Author: Dmitry Baryshnikov, dmitry.baryshnikov@nextgis.com
5  *
6  ******************************************************************************
7  * Copyright (c) 2017-2018 NextGIS, <info@nextgis.com>
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
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11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included
17  * in all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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25  * DEALINGS IN THE SOFTWARE.
26  ****************************************************************************/
27 
28 #ifndef CPL_JSON_H_INCLUDED
29 #define CPL_JSON_H_INCLUDED
30 
31 #include "cpl_progress.h"
32 #include "cpl_string.h"
33 
34 #include <string>
35 #include <vector>
36 
44 typedef void *JSONObjectH;
45 
47 
48 class CPLJSONArray;
54 class CPL_DLL CPLJSONObject
55 {
56  friend class CPLJSONArray;
57  friend class CPLJSONDocument;
58 
59  public:
63  enum class Type
64  {
65  Unknown,
66  Null,
67  Object,
68  Array,
69  Boolean,
70  String,
71  Integer,
72  Long,
73  Double
74  };
75 
79  enum class PrettyFormat
80  {
81  Plain,
82  Spaced,
83  Pretty
84  };
85 
86  public:
88  CPLJSONObject();
89  explicit CPLJSONObject(const std::string &osName,
90  const CPLJSONObject &oParent);
91  ~CPLJSONObject();
92  CPLJSONObject(const CPLJSONObject &other);
94  CPLJSONObject &operator=(const CPLJSONObject &other);
95  CPLJSONObject &operator=(CPLJSONObject &&other);
96 
97  private:
98  explicit CPLJSONObject(const std::string &osName, JSONObjectH poJsonObject);
101  public:
102  // setters
103  void Add(const std::string &osName, const std::string &osValue);
104  void Add(const std::string &osName, const char *pszValue);
105  void Add(const std::string &osName, double dfValue);
106  void Add(const std::string &osName, int nValue);
107  void Add(const std::string &osName, GInt64 nValue);
108  void Add(const std::string &osName, const CPLJSONArray &oValue);
109  void Add(const std::string &osName, const CPLJSONObject &oValue);
110  void AddNoSplitName(const std::string &osName, const CPLJSONObject &oValue);
111  void Add(const std::string &osName, bool bValue);
112  void AddNull(const std::string &osName);
113 
114  void Set(const std::string &osName, const std::string &osValue);
115  void Set(const std::string &osName, const char *pszValue);
116  void Set(const std::string &osName, double dfValue);
117  void Set(const std::string &osName, int nValue);
118  void Set(const std::string &osName, GInt64 nValue);
119  void Set(const std::string &osName, bool bValue);
120  void SetNull(const std::string &osName);
121 
123  JSONObjectH GetInternalHandle() const
124  {
125  return m_poJsonObject;
126  }
129  // getters
130  std::string GetString(const std::string &osName,
131  const std::string &osDefault = "") const;
132  double GetDouble(const std::string &osName, double dfDefault = 0.0) const;
133  int GetInteger(const std::string &osName, int nDefault = 0) const;
134  GInt64 GetLong(const std::string &osName, GInt64 nDefault = 0) const;
135  bool GetBool(const std::string &osName, bool bDefault = false) const;
136  std::string ToString(const std::string &osDefault = "") const;
137  double ToDouble(double dfDefault = 0.0) const;
138  int ToInteger(int nDefault = 0) const;
139  GInt64 ToLong(GInt64 nDefault = 0) const;
140  bool ToBool(bool bDefault = false) const;
141  CPLJSONArray ToArray() const;
142  std::string Format(PrettyFormat eFormat) const;
143 
144  //
145  void Delete(const std::string &osName);
146  void DeleteNoSplitName(const std::string &osName);
147  CPLJSONArray GetArray(const std::string &osName) const;
148  CPLJSONObject GetObj(const std::string &osName) const;
149  CPLJSONObject operator[](const std::string &osName) const;
150  Type GetType() const;
152  std::string GetName() const
153  {
154  return m_osKey;
155  }
158  std::vector<CPLJSONObject> GetChildren() const;
159  bool IsValid() const;
160  void Deinit();
161 
162  protected:
164  CPLJSONObject GetObjectByPath(const std::string &osPath,
165  std::string &osName) const;
168  private:
169  JSONObjectH m_poJsonObject = nullptr;
170  std::string m_osKey{};
171 };
172 
176 class CPL_DLL CPLJSONArray : public CPLJSONObject
177 {
178  friend class CPLJSONObject;
179  friend class CPLJSONDocument;
180 
181  public:
183  CPLJSONArray();
184  explicit CPLJSONArray(const std::string &osName);
185  explicit CPLJSONArray(const CPLJSONObject &other);
186 
187  private:
188  explicit CPLJSONArray(const std::string &osName, JSONObjectH poJsonObject);
189 
190  class CPL_DLL ConstIterator
191  {
192  const CPLJSONArray &m_oSelf;
193  int m_nIdx;
194  mutable CPLJSONObject m_oObj{};
195 
196  public:
197  ConstIterator(const CPLJSONArray &oSelf, bool bStart)
198  : m_oSelf(oSelf), m_nIdx(bStart ? 0 : oSelf.Size())
199  {
200  }
201  ~ConstIterator() = default;
202  CPLJSONObject &operator*() const
203  {
204  m_oObj = m_oSelf[m_nIdx];
205  return m_oObj;
206  }
207  ConstIterator &operator++()
208  {
209  m_nIdx++;
210  return *this;
211  }
212  bool operator==(const ConstIterator &it) const
213  {
214  return m_nIdx == it.m_nIdx;
215  }
216  bool operator!=(const ConstIterator &it) const
217  {
218  return m_nIdx != it.m_nIdx;
219  }
220  };
221 
223  public:
224  int Size() const;
225  void Add(const CPLJSONObject &oValue);
226  void Add(const std::string &osValue);
227  void Add(const char *pszValue);
228  void Add(double dfValue);
229  void Add(int nValue);
230  void Add(GInt64 nValue);
231  void Add(bool bValue);
232  CPLJSONObject operator[](int nIndex);
233  const CPLJSONObject operator[](int nIndex) const;
234 
236  ConstIterator begin() const
237  {
238  return ConstIterator(*this, true);
239  }
241  ConstIterator end() const
242  {
243  return ConstIterator(*this, false);
244  }
245 };
246 
250 class CPL_DLL CPLJSONDocument
251 {
252  public:
254  CPLJSONDocument();
255  ~CPLJSONDocument();
256  CPLJSONDocument(const CPLJSONDocument &other);
257  CPLJSONDocument &operator=(const CPLJSONDocument &other);
259  CPLJSONDocument &operator=(CPLJSONDocument &&other);
262  bool Save(const std::string &osPath) const;
263  std::string SaveAsString() const;
264 
265  CPLJSONObject GetRoot();
266  const CPLJSONObject GetRoot() const;
267  void SetRoot(const CPLJSONObject &oRoot);
268  bool Load(const std::string &osPath);
269  bool LoadMemory(const std::string &osStr);
270  bool LoadMemory(const GByte *pabyData, int nLength = -1);
271  bool LoadChunks(const std::string &osPath, size_t nChunkSize = 16384,
272  GDALProgressFunc pfnProgress = nullptr,
273  void *pProgressArg = nullptr);
274  bool LoadUrl(const std::string &osUrl, const char *const *papszOptions,
275  GDALProgressFunc pfnProgress = nullptr,
276  void *pProgressArg = nullptr);
277 
278  private:
279  mutable JSONObjectH m_poRootJsonObject;
280 };
281 
282 CPL_C_END
283 
284 #if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS)
285 extern "C++"
286 {
287  CPLStringList CPLParseKeyValueJson(const char *pszJson);
288 }
289 #endif
290 
291 #endif // CPL_JSON_H_INCLUDED
CPLJSONArray
The JSONArray class JSON array from JSONDocument.
Definition: cpl_json.h:176
GByte
unsigned char GByte
Unsigned byte type.
Definition: cpl_port.h:205
CPLStringList
String list class designed around our use of C "char**" string lists.
Definition: cpl_string.h:437
CPLParseKeyValueJson
CPLStringList CPLParseKeyValueJson(const char *pszJson)
Return a string list of key/value pairs extracted from a JSON doc.
Definition: cpl_json.cpp:1488
GInt64
GIntBig GInt64
Signed 64 bit integer type.
Definition: cpl_port.h:256
CPL_C_START
#define CPL_C_START
Macro to start a block of C symbols.
Definition: cpl_port.h:315
CPLJSONObject::PrettyFormat
PrettyFormat
Json object format to string options.
Definition: cpl_json.h:79
CPLJSONObject
The CPLJSONArray class holds JSON object from CPLJSONDocument.
Definition: cpl_json.h:54
CPLJSONArray::end
ConstIterator end() const
Iterator to after last element.
Definition: cpl_json.h:241
CPL_C_END
#define CPL_C_END
Macro to end a block of C symbols.
Definition: cpl_port.h:319
CPLJSONObject::Type
Type
Json object types.
Definition: cpl_json.h:63
cpl_string.h
CPLJSONArray::Size
int Size() const
Get array size.
Definition: cpl_json.cpp:1337
CPLJSONArray::begin
ConstIterator begin() const
Iterator to first element.
Definition: cpl_json.h:236
CPLJSONDocument
The CPLJSONDocument class Wrapper class around json-c library.
Definition: cpl_json.h:250