MongoDB C++ Driver  mongocxx-3.7.0
read_preference.hpp
1 // Copyright 2014 MongoDB Inc.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #pragma once
16 
17 #include <chrono>
18 #include <cstdint>
19 #include <memory>
20 #include <string>
21 
22 #include <bsoncxx/array/view_or_value.hpp>
23 #include <bsoncxx/document/view_or_value.hpp>
24 #include <bsoncxx/stdx/optional.hpp>
25 #include <mongocxx/options/transaction.hpp>
26 #include <mongocxx/stdx.hpp>
27 
28 #include <mongocxx/config/prelude.hpp>
29 
30 namespace mongocxx {
31 MONGOCXX_INLINE_NAMESPACE_BEGIN
32 
33 class client;
34 class collection;
35 class database;
36 class uri;
37 
38 namespace events {
39 class topology_description;
40 }
41 
63 class MONGOCXX_API read_preference {
64  public:
76  enum class read_mode : std::uint8_t {
80  k_primary,
81 
85  k_primary_preferred,
86 
90  k_secondary,
91 
95  k_secondary_preferred,
96 
100  k_nearest
101  };
102 
106  read_preference();
107 
108  struct deprecated_tag {};
109 
118  MONGOCXX_DEPRECATED read_preference(read_mode mode);
120 
133  MONGOCXX_DEPRECATED read_preference(read_mode mode, bsoncxx::document::view_or_value tags);
135 
140 
144  read_preference& operator=(const read_preference&);
145 
149  read_preference(read_preference&&) noexcept;
150 
154  read_preference& operator=(read_preference&&) noexcept;
155 
159  ~read_preference();
160 
171  read_preference& mode(read_mode mode);
172 
178  read_mode mode() const;
179 
192  read_preference& tags(bsoncxx::document::view_or_value tag_set_list);
193 
206  read_preference& tags(bsoncxx::array::view_or_value tag_set_list);
207 
215  stdx::optional<bsoncxx::document::view> tags() const;
216 
247  read_preference& max_staleness(std::chrono::seconds max_staleness);
248 
254  stdx::optional<std::chrono::seconds> max_staleness() const;
255 
274  read_preference& hedge(bsoncxx::document::view_or_value hedge);
275 
281  const stdx::optional<bsoncxx::document::view> hedge() const;
282 
283  private:
284  friend client;
285  friend collection;
286  friend database;
288  friend mongocxx::options::transaction;
290  friend mongocxx::events::topology_description;
291  friend uri;
292 
300  friend MONGOCXX_API bool MONGOCXX_CALL operator==(const read_preference&,
301  const read_preference&);
302  friend MONGOCXX_API bool MONGOCXX_CALL operator!=(const read_preference&,
303  const read_preference&);
307 
308  class MONGOCXX_PRIVATE impl;
309 
310  MONGOCXX_PRIVATE read_preference(std::unique_ptr<impl>&& implementation);
311 
312  std::unique_ptr<impl> _impl;
313 };
314 
315 MONGOCXX_INLINE_NAMESPACE_END
316 } // namespace mongocxx
317 
318 #include <mongocxx/config/postlude.hpp>
mongocxx
Top level namespace for the MongoDB C++ driver.
Definition: bulk_write.hpp:24
bsoncxx
Top level namespace for MongoDB C++ BSON functionality.
Definition: element.hpp:24
bsoncxx::view_or_value< document::view, document::value >
mongocxx::client
Class representing a client connection to MongoDB.
Definition: client.hpp:58
mongocxx::read_preference
Class representing a preference for how the driver routes read operations to members of a replica set...
Definition: read_preference.hpp:63
mongocxx::uri
Class representing a MongoDB connection string URI.
Definition: uri.hpp:43
mongocxx::read_preference::deprecated_tag
Definition: read_preference.hpp:108
mongocxx::read_preference::read_mode
read_mode
Determines which members in a replica set are acceptable to read from.
Definition: read_preference.hpp:76
mongocxx::database
Class representing a MongoDB database.
Definition: database.hpp:43
mongocxx::collection
Class representing server side document groupings within a MongoDB database.
Definition: collection.hpp:83