db_mongoc.h
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1/*!
2 * \file db_mongoc.h
3 * \brief Simple wrappers of the API of MongoDB C driver `mongo-c-driver`,
4 * see <a href="http://mongoc.org/">MongoDB C Driver</a> for more information.
5 *
6 * \remarks
7 * - 1. 2017-12-02 - lj - Add unittest based on gtest/gmock.
8 * - 2. 2018-05-02 - lj - Make part of CCGL.
9 * - 3. 2019-08-16 - lj - Simplify brief desc. and move detail desc. to implementation.
10 *
11 * \note No exceptions will be thrown.
12 * \author Liangjun Zhu, zlj(at)lreis.ac.cn
13 * \version 1.2
14 */
15#ifndef CCGL_DB_MONGOC_H
16#define CCGL_DB_MONGOC_H
17#ifdef USE_MONGODB
18
19#include <vector>
20#include <map>
21#include <iostream>
22
23#include <mongoc.h>
24
25#include "basic.h"
26
27using std::string;
28using std::vector;
29using std::map;
30using std::cout;
31using std::endl;
32
33namespace ccgl {
34/*!
35 * \namespace ccgl::db_mongoc
36 * \brief Simple wrappers of the API of MongoDB C driver `mongo-c-driver`,
37 * see <a href="http://mongoc.org/">MongoDB C Driver</a> for more information.
38 */
39namespace db_mongoc {
40class MongoGridFs;
41
42/*!
43 * \class MongoClient
44 * \brief A simple wrapper of the class of MongoDB Client `mongoc_client_t`.
45 */
47public:
48 /*! Constructor using IP address and port number */
49 MongoClient(const char* host, vuint16_t port);
50
51 /*! Constructor using mongoc_client_t* */
52 MongoClient(mongoc_client_t* conn);
53
54 /*! Initialization of MongoClient with the validation check of database */
55 static MongoClient* Init(const char* host, vuint16_t port);
56
57 /*! Destructor */
59
60 /*! Destroy explicitly */
61 void Destroy();
62
63 /*! Get `mongoc_client_t` instance */
64 mongoc_client_t* GetConn() { return conn_; }
65
66 /*! Get existing or newly created `mongoc_database_t` instance */
67 mongoc_database_t* GetDatabase(string const& dbname);
68
69 /*! Get `mongoc_collection_t` instance */
70 mongoc_collection_t* GetCollection(string const& dbname, string const& collectionname);
71
72 /*! Get `mongoc_gridfs_t` instance */
73 mongoc_gridfs_t* GetGridFs(string const& dbname, string const& gfsname);
74
75 /*! Get MongoGridFs instance */
76 MongoGridFs* GridFs(string const& dbname, string const& gfsname);
77
78 /*! Get existing database names */
79 void GetDatabaseNames(vector<string>& dbnames);
80
81 /*! Get collection names in MongoDB database */
82 void GetCollectionNames(string const& dbname, vector<string>& collnames);
83
84 /*! Get GridFs file names in MongoDB database */
85 void GetGridFsFileNames(string const& dbname, string const& gfsname, vector<string>& gfs_exists);
86
87private:
88 const char* host_; ///< Host IP address of MongoDB
89 vuint16_t port_; ///< Port number
90 mongoc_client_t* conn_; ///< Instance of `mongoc_client_t`
91};
92
93/*!
94 * \class MongoDatabase
95 * \brief A simple wrapper of the class of MongoDB database `mongoc_database_t`.
96 */
98public:
99 /*! Constructor by a `mongoc_database_t` pointer */
100 explicit MongoDatabase(mongoc_database_t* db);
101
102 /*! Constructor by mongodb client (`mongoc_client_t` pointer) and database name */
103 MongoDatabase(mongoc_client_t* conn, string& dbname);
104
105 /*! Destructor */
107
108 /*! Get collection names in current database */
109 void GetCollectionNames(vector<string>& collnames);
110
111private:
112 mongoc_database_t* db_; ///< Instance of `mongoc_database_t`
113 string dbname_; ///< Database name
114};
115
116/*!
117* \class MongoCollection
118* \brief A simple wrapper of the class of MongoDB Collection `mongoc_collection_t`.
119*/
121public:
122 /*! Constructor by a `mongoc_collection_t` pointer */
123 explicit MongoCollection(mongoc_collection_t* coll);
124
125 /*! Destructor */
127
128 /*! Execute query */
129 mongoc_cursor_t* ExecuteQuery(const bson_t* b, const bson_t* opts = nullptr);
130
131 /*! Query the records number */
133private:
134 mongoc_collection_t* collection_; ///< Instance of `mongoc_collection_t`
135};
136
137/*!
138 * \class MongoGridFs
139 * \brief A simple wrapper of the class of MongoDB database `mongoc_gridfs_t`.
140 */
142public:
143 /*! Constructor by a `mongoc_gridfs_t` pointer or NULL */
144 explicit MongoGridFs(mongoc_gridfs_t* gfs = NULL);
145
146 /*! Destructor */
148
149 /*! Get the current instance of `mongoc_gridfs_t` */
150 mongoc_gridfs_t* GetGridFs() { return gfs_; }
151
152 /*! Get GridFS file by name */
153 mongoc_gridfs_file_t* GetFile(string const& gfilename, mongoc_gridfs_t* gfs = NULL,
154 const STRING_MAP& opts = STRING_MAP());
155
156 /*! Remove GridFS all matching files and their data chunks. */
157 bool RemoveFile(string const& gfilename, mongoc_gridfs_t* gfs = NULL,
158 STRING_MAP opts = STRING_MAP());
159
160 /*! Get GridFS file names */
161 void GetFileNames(vector<string>& files_existed, mongoc_gridfs_t* gfs = NULL);
162
163 /*! Get metadata of a given GridFS file name, remember to destory bson_t after use */
164 bson_t* GetFileMetadata(string const& gfilename, mongoc_gridfs_t* gfs = NULL,
165 STRING_MAP opts = STRING_MAP());
166
167 /*! Get stream data of a given GridFS file name */
168 bool GetStreamData(string const& gfilename, char*& databuf, vint& datalength,
169 mongoc_gridfs_t* gfs = NULL,
170 const STRING_MAP* opts = nullptr);
171
172 /*! Write stream data to a GridFS file */
173 bool WriteStreamData(const string& gfilename, char*& buf, vint length,
174 const bson_t* p, mongoc_gridfs_t* gfs = NULL);
175
176private:
177 mongoc_gridfs_t* gfs_; ///< Instance of `mongoc_gridfs_t`
178};
179
180/*! Append options to `bson_t` */
181void AppendStringOptionsToBson(bson_t* bson_opts, const STRING_MAP& opts,
182 const string& prefix = string());
183
184/*!
185 * \brief Get numeric value from the iterator (`bson_iter_t`) of `bson_t`according to a given key
186 * \param[in] iter Iterator of an instance of `bson_t`
187 * \param[in,out] numericvalue The extracted value which can be `int`, `float`, or `double`
188 * \return true if succeed, otherwise false.
189 */
190template <typename T>
191bool GetNumericFromBsonIterator(bson_iter_t* iter, T& numericvalue) {
192 const bson_value_t* vv = bson_iter_value(iter);
193 if (vv->value_type == BSON_TYPE_INT32) {
194 numericvalue = static_cast<T>(vv->value.v_int32);
195 } else if (vv->value_type == BSON_TYPE_INT64) {
196 numericvalue = static_cast<T>(vv->value.v_int64);
197 } else if (vv->value_type == BSON_TYPE_DOUBLE) {
198 numericvalue = static_cast<T>(vv->value.v_double);
199 } else if (vv->value_type == BSON_TYPE_UTF8) {
200 string tmp = vv->value.v_utf8.str;
201 if (tmp.find_first_of("0123456789") == string::npos) {
202 cout << "bson iterator isn't or not contains a numeric value." << endl;
203 return false;
204 }
205 char* end = nullptr;
206 numericvalue = static_cast<T>(strtod(tmp.c_str(), &end));
207 } else {
208 cout << "bson iterator isn't or not contains a numeric value." << endl;
209 return false;
210 }
211 return true;
212}
213
214/*!
215 * \brief Get numeric value from `bson_t` according to a given key
216 * \param[in] bmeta Instance of `bson_t`
217 * \param[in] key
218 * \param[in,out] numericvalue The extracted value which can be `int`, `float`, or `double`
219 * \return true if succeed, otherwise false.
220 * \sa GetNumericFromBsonIterator()
221 */
222template <typename T>
223bool GetNumericFromBson(bson_t* bmeta, const char* key, T& numericvalue) {
224 bson_iter_t iter;
225 if (bson_iter_init(&iter, bmeta) && bson_iter_find(&iter, key)) {
226 return GetNumericFromBsonIterator(&iter, numericvalue);
227 }
228 StatusMessage(("WARNING: GetNumericFromBson, Failed in get value of: " + string(key) + "\n").c_str());
229 return false;
230}
231
232/*!
233 * \brief Get String from the iterator (`bson_iter_t`) of `bson_t`
234 * \param[in] iter Iterator of an instance of `bson_t`
235 * \return String of value if succeed, otherwise empty string ("").
236 */
237string GetStringFromBsonIterator(bson_iter_t* iter);
238
239/*!
240 * \brief Get String from `bson_t`
241 * \param[in] bmeta Instance of `bson_t`
242 * \param[in] key
243 * \return String of value if succeed, otherwise empty string ("").
244 * \sa GetStringFromBsonIterator()
245 */
246string GetStringFromBson(bson_t* bmeta, const char* key);
247
248/*!
249 * \brief Get Bool from the iterator (`bson_iter_t`) of `bson_t`
250 * \param[in] iter Iterator of an instance of `bson_t`
251 * \return true if succeed, otherwise false.
252 */
253bool GetBoolFromBsonIterator(bson_iter_t* iter);
254
255/*!
256 * \brief Get String from `bson_t`
257 * \param[in] bmeta Instance of `bson_t`
258 * \param[in] key
259 * \return true if succeed, otherwise false.]
260 * \sa GetBoolFromBsonIterator()
261 */
262bool GetBoolFromBson(bson_t* bmeta, const char* key);
263
264/*!
265 * \brief Get Datetime from the iterator (`bson_iter_t`) of `bson_t`
266 * \param[in] iter Iterator of an instance of `bson_t`
267 * \return float value (`time_t`) if succeed, otherwise -1.
268 */
269time_t GetDatetimeFromBsonIterator(bson_iter_t* iter);
270
271/*!
272 * \brief Get Datetime from `bson_t`
273 * \param[in] bmeta Instance of `bson_t`
274 * \param[in] key
275 * \return float value (`time_t`) if succeed, otherwise -1.
276 * \sa GetDatetimeFromBsonIterator()
277 */
278time_t GetDatetimeFromBson(bson_t* bmeta, const char* key);
279} /* namespace: db_mongoc */
280} /* namespace: ccgl */
281
282#endif /* USE_MONGODB */
283#endif /* CCGL_DB_MONGOC_H */
Basic definitions.
Base class for classes that cannot be copied.
Definition: basic.h:385
A simple wrapper of the class of MongoDB Client mongoc_client_t.
Definition: db_mongoc.h:46
MongoClient(mongoc_client_t *conn)
Constructor using mongoc_client_t*.
void GetDatabaseNames(vector< string > &dbnames)
Get existing database names.
mongoc_database_t * GetDatabase(string const &dbname)
Get existing or newly created mongoc_database_t instance.
mongoc_collection_t * GetCollection(string const &dbname, string const &collectionname)
Get mongoc_collection_t instance.
mongoc_client_t * GetConn()
Get mongoc_client_t instance.
Definition: db_mongoc.h:64
MongoClient(const char *host, vuint16_t port)
Constructor using IP address and port number.
void Destroy()
Destroy explicitly.
mongoc_gridfs_t * GetGridFs(string const &dbname, string const &gfsname)
Get mongoc_gridfs_t instance.
static MongoClient * Init(const char *host, vuint16_t port)
Initialization of MongoClient with the validation check of database.
void GetGridFsFileNames(string const &dbname, string const &gfsname, vector< string > &gfs_exists)
Get GridFs file names in MongoDB database.
MongoGridFs * GridFs(string const &dbname, string const &gfsname)
Get MongoGridFs instance.
void GetCollectionNames(string const &dbname, vector< string > &collnames)
Get collection names in MongoDB database.
A simple wrapper of the class of MongoDB Collection mongoc_collection_t.
Definition: db_mongoc.h:120
mongoc_cursor_t * ExecuteQuery(const bson_t *b, const bson_t *opts=nullptr)
Execute query.
MongoCollection(mongoc_collection_t *coll)
Constructor by a mongoc_collection_t pointer.
vint QueryRecordsCount()
Query the records number.
A simple wrapper of the class of MongoDB database mongoc_database_t.
Definition: db_mongoc.h:97
MongoDatabase(mongoc_database_t *db)
Constructor by a mongoc_database_t pointer.
void GetCollectionNames(vector< string > &collnames)
Get collection names in current database.
MongoDatabase(mongoc_client_t *conn, string &dbname)
Constructor by mongodb client (mongoc_client_t pointer) and database name.
A simple wrapper of the class of MongoDB database mongoc_gridfs_t.
Definition: db_mongoc.h:141
void GetFileNames(vector< string > &files_existed, mongoc_gridfs_t *gfs=NULL)
Get GridFS file names.
bool RemoveFile(string const &gfilename, mongoc_gridfs_t *gfs=NULL, STRING_MAP opts=STRING_MAP())
Remove GridFS all matching files and their data chunks.
mongoc_gridfs_file_t * GetFile(string const &gfilename, mongoc_gridfs_t *gfs=NULL, const STRING_MAP &opts=STRING_MAP())
Get GridFS file by name.
MongoGridFs(mongoc_gridfs_t *gfs=NULL)
Constructor by a mongoc_gridfs_t pointer or NULL.
bool GetStreamData(string const &gfilename, char *&databuf, vint &datalength, mongoc_gridfs_t *gfs=NULL, const STRING_MAP *opts=nullptr)
Get stream data of a given GridFS file name.
bool WriteStreamData(const string &gfilename, char *&buf, vint length, const bson_t *p, mongoc_gridfs_t *gfs=NULL)
Write stream data to a GridFS file.
bson_t * GetFileMetadata(string const &gfilename, mongoc_gridfs_t *gfs=NULL, STRING_MAP opts=STRING_MAP())
Get metadata of a given GridFS file name, remember to destory bson_t after use.
mongoc_gridfs_t * GetGridFs()
Get the current instance of mongoc_gridfs_t
Definition: db_mongoc.h:150
bool GetNumericFromBson(bson_t *bmeta, const char *key, T &numericvalue)
Get numeric value from bson_t according to a given key.
Definition: db_mongoc.h:223
void AppendStringOptionsToBson(bson_t *bson_opts, const STRING_MAP &opts, const string &prefix=string())
Append options to bson_t
string GetStringFromBsonIterator(bson_iter_t *iter)
Get String from the iterator (bson_iter_t) of bson_t
bool GetBoolFromBsonIterator(bson_iter_t *iter)
Get Bool from the iterator (bson_iter_t) of bson_t
time_t GetDatetimeFromBsonIterator(bson_iter_t *iter)
Get Datetime from the iterator (bson_iter_t) of bson_t
string GetStringFromBson(bson_t *bmeta, const char *key)
Get String from bson_t
bool GetNumericFromBsonIterator(bson_iter_t *iter, T &numericvalue)
Get numeric value from the iterator (bson_iter_t) of bson_taccording to a given key.
Definition: db_mongoc.h:191
time_t GetDatetimeFromBson(bson_t *bmeta, const char *key)
Get Datetime from bson_t
bool GetBoolFromBson(bson_t *bmeta, const char *key)
Get String from bson_t
Common Cross-platform Geographic Library (CCGL)
std::map< string, string > STRING_MAP
Map of string key and string value.
Definition: basic.h:349
void StatusMessage(const char *msg)
Print status messages for Debug.