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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
10 * copy of this software and associated documentation files (the "Software"),
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
22 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
24 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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
46 CPL_C_START
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 explicit CPLJSONObject(std::nullptr_t);
92 explicit CPLJSONObject(const std::string &osVal);
93 explicit CPLJSONObject(const char *pszValue);
94 explicit CPLJSONObject(bool bVal);
95 explicit CPLJSONObject(int nVal);
96 explicit CPLJSONObject(int64_t nVal);
97 explicit CPLJSONObject(uint64_t nVal);
98 explicit CPLJSONObject(double dfVal);
99 ~CPLJSONObject();
100 CPLJSONObject(const CPLJSONObject &other);
101 CPLJSONObject(CPLJSONObject &&other);
102 CPLJSONObject &operator=(const CPLJSONObject &other);
103 CPLJSONObject &operator=(CPLJSONObject &&other);
104
105 // This method is not thread-safe
106 CPLJSONObject Clone() const;
107
108 private:
109 explicit CPLJSONObject(const std::string &osName, JSONObjectH poJsonObject);
112 public:
113 // setters
114 void Add(const std::string &osName, const std::string &osValue);
115 void Add(const std::string &osName, const char *pszValue);
116 void Add(const std::string &osName, double dfValue);
117 void Add(const std::string &osName, int nValue);
118 void Add(const std::string &osName, GInt64 nValue);
119 void Add(const std::string &osName, uint64_t nValue);
120 void Add(const std::string &osName, const CPLJSONArray &oValue);
121 void Add(const std::string &osName, const CPLJSONObject &oValue);
122 void AddNoSplitName(const std::string &osName, const CPLJSONObject &oValue);
123 void Add(const std::string &osName, bool bValue);
124 void AddNull(const std::string &osName);
125
126 void Set(const std::string &osName, const std::string &osValue);
127 void Set(const std::string &osName, const char *pszValue);
128 void Set(const std::string &osName, double dfValue);
129 void Set(const std::string &osName, int nValue);
130 void Set(const std::string &osName, GInt64 nValue);
131 void Set(const std::string &osName, uint64_t nValue);
132 void Set(const std::string &osName, bool bValue);
133 void SetNull(const std::string &osName);
134
136 JSONObjectH GetInternalHandle() const
137 {
138 return m_poJsonObject;
139 }
142 // getters
143 std::string GetString(const std::string &osName,
144 const std::string &osDefault = "") const;
145 double GetDouble(const std::string &osName, double dfDefault = 0.0) const;
146 int GetInteger(const std::string &osName, int nDefault = 0) const;
147 GInt64 GetLong(const std::string &osName, GInt64 nDefault = 0) const;
148 bool GetBool(const std::string &osName, bool bDefault = false) const;
149 std::string ToString(const std::string &osDefault = "") const;
150 double ToDouble(double dfDefault = 0.0) const;
151 int ToInteger(int nDefault = 0) const;
152 GInt64 ToLong(GInt64 nDefault = 0) const;
153 bool ToBool(bool bDefault = false) const;
154 CPLJSONArray ToArray() const;
155 std::string Format(PrettyFormat eFormat) const;
156
157 //
158 void Delete(const std::string &osName);
159 void DeleteNoSplitName(const std::string &osName);
160 CPLJSONArray GetArray(const std::string &osName) const;
161 CPLJSONObject GetObj(const std::string &osName) const;
162 CPLJSONObject operator[](const std::string &osName) const;
163 Type GetType() const;
165 std::string GetName() const
166 {
167 return m_osKey;
168 }
171 std::vector<CPLJSONObject> GetChildren() const;
172 bool IsValid() const;
173 void Deinit();
174
175 protected:
177 CPLJSONObject GetObjectByPath(const std::string &osPath,
178 std::string &osName) const;
181 private:
182 JSONObjectH m_poJsonObject = nullptr;
183 std::string m_osKey{};
184 };
185
189 class CPL_DLL CPLJSONArray : public CPLJSONObject
190 {
191 friend class CPLJSONObject;
192 friend class CPLJSONDocument;
193
194 public:
196 CPLJSONArray();
197 explicit CPLJSONArray(const std::string &osName);
198 explicit CPLJSONArray(const CPLJSONObject &other);
199
200 private:
201 explicit CPLJSONArray(const std::string &osName, JSONObjectH poJsonObject);
202
203 class CPL_DLL ConstIterator
204 {
205 const CPLJSONArray &m_oSelf;
206 int m_nIdx;
207 mutable CPLJSONObject m_oObj{};
208
209 public:
210 ConstIterator(const CPLJSONArray &oSelf, bool bStart)
211 : m_oSelf(oSelf), m_nIdx(bStart ? 0 : oSelf.Size())
212 {
213 }
214 ~ConstIterator() = default;
215 CPLJSONObject &operator*() const
216 {
217 m_oObj = m_oSelf[m_nIdx];
218 return m_oObj;
219 }
220 ConstIterator &operator++()
221 {
222 m_nIdx++;
223 return *this;
224 }
225 bool operator==(const ConstIterator &it) const
226 {
227 return m_nIdx == it.m_nIdx;
228 }
229 bool operator!=(const ConstIterator &it) const
230 {
231 return m_nIdx != it.m_nIdx;
232 }
233 };
234
236 public:
237 int Size() const;
238 void AddNull();
239 void Add(const CPLJSONObject &oValue);
240 void Add(const std::string &osValue);
241 void Add(const char *pszValue);
242 void Add(double dfValue);
243 void Add(int nValue);
244 void Add(GInt64 nValue);
245 void Add(uint64_t nValue);
246 void Add(bool bValue);
247 CPLJSONObject operator[](int nIndex);
248 const CPLJSONObject operator[](int nIndex) const;
249
251 ConstIterator begin() const
252 {
253 return ConstIterator(*this, true);
254 }
256 ConstIterator end() const
257 {
258 return ConstIterator(*this, false);
259 }
260 };
261
265 class CPL_DLL CPLJSONDocument
266 {
267 public:
269 CPLJSONDocument();
270 ~CPLJSONDocument();
271 CPLJSONDocument(const CPLJSONDocument &other);
272 CPLJSONDocument &operator=(const CPLJSONDocument &other);
273 CPLJSONDocument(CPLJSONDocument &&other);
274 CPLJSONDocument &operator=(CPLJSONDocument &&other);
277 bool Save(const std::string &osPath) const;
278 std::string SaveAsString() const;
279
280 CPLJSONObject GetRoot();
281 const CPLJSONObject GetRoot() const;
282 void SetRoot(const CPLJSONObject &oRoot);
283 bool Load(const std::string &osPath);
284 bool LoadMemory(const std::string &osStr);
285 bool LoadMemory(const GByte *pabyData, int nLength = -1);
286 bool LoadChunks(const std::string &osPath, size_t nChunkSize = 16384,
287 GDALProgressFunc pfnProgress = nullptr,
288 void *pProgressArg = nullptr);
289 bool LoadUrl(const std::string &osUrl, const char *const *papszOptions,
290 GDALProgressFunc pfnProgress = nullptr,
291 void *pProgressArg = nullptr);
292
293 private:
294 mutable JSONObjectH m_poRootJsonObject;
295 };
296
297 CPL_C_END
298
299 #if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS)
300 extern "C++"
301 {
302 CPLStringList CPLParseKeyValueJson(const char *pszJson);
303 }
304 #endif
305
306 #endif // CPL_JSON_H_INCLUDED
CPLJSONArray
The JSONArray class JSON array from JSONDocument.
Definition: cpl_json.h:189
GByte
unsigned char GByte
Unsigned byte type.
Definition: cpl_port.h:196
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:1629
GInt64
GIntBig GInt64
Signed 64 bit integer type.
Definition: cpl_port.h:247
CPL_C_START
#define CPL_C_START
Macro to start a block of C symbols.
Definition: cpl_port.h:306
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:256
CPL_C_END
#define CPL_C_END
Macro to end a block of C symbols.
Definition: cpl_port.h:310
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:1452
CPLJSONArray::begin
ConstIterator begin() const
Iterator to first element.
Definition: cpl_json.h:251
CPLJSONDocument
The CPLJSONDocument class Wrapper class around json-c library.
Definition: cpl_json.h:265