1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
|
/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <string>
#include <vector>
#include "mongo/base/status.h"
#include "mongo/db/repl/member_id.h"
#include "mongo/db/repl/repl_set_tag.h"
#include "mongo/db/repl/split_horizon.h"
#include "mongo/util/net/hostandport.h"
#include "mongo/util/string_map.h"
#include "mongo/util/time_support.h"
namespace mongo {
class BSONObj;
namespace repl {
/**
* Representation of the configuration information about a particular member of a replica set.
*/
class MemberConfig {
public:
typedef std::vector<ReplSetTag>::const_iterator TagIterator;
static const std::string kIdFieldName;
static const std::string kVotesFieldName;
static const std::string kPriorityFieldName;
static const std::string kHostFieldName;
static const std::string kHiddenFieldName;
static const std::string kSlaveDelayFieldName;
static const std::string kArbiterOnlyFieldName;
static const std::string kBuildIndexesFieldName;
static const std::string kTagsFieldName;
static const std::string kHorizonsFieldName;
static const std::string kInternalVoterTagName;
static const std::string kInternalElectableTagName;
static const std::string kInternalAllTagName;
/**
* Construct a MemberConfig from the contents of "mcfg".
*
* If "mcfg" describes any tags, builds ReplSetTags for this
* configuration using "tagConfig" as the tag's namespace. This may
* have the effect of altering "tagConfig" when "mcfg" describes a
* tag not previously added to "tagConfig".
*/
MemberConfig(const BSONObj& mcfg, ReplSetTagConfig* tagConfig);
/**
* Performs basic consistency checks on the member configuration.
*/
Status validate() const;
/**
* Gets the identifier for this member, unique within a ReplSetConfig.
*/
MemberId getId() const {
return _id;
}
/**
* Gets the canonical name of this member, by which other members and clients
* will contact it.
*/
const HostAndPort& getHostAndPort(StringData horizon = SplitHorizon::kDefaultHorizon) const {
return _splitHorizon.getHostAndPort(horizon);
}
/**
* Gets the mapping of horizon names to `HostAndPort` for this replica set member.
*/
const auto& getHorizonMappings() const {
return _splitHorizon.getForwardMappings();
}
/**
* Gets the mapping of host names (not `HostAndPort`) to horizon names for this replica set
* member.
*/
const auto& getHorizonReverseHostMappings() const {
return _splitHorizon.getReverseHostMappings();
}
/**
* Gets the horizon name for which the parameters (captured during the first `isMaster`)
* correspond.
*/
StringData determineHorizon(const SplitHorizon::Parameters& params) const {
return _splitHorizon.determineHorizon(params);
}
/**
* Gets this member's priority. Higher means more likely to be elected
* primary.
*/
double getPriority() const {
return _priority;
}
/**
* Gets the amount of time behind the primary that this member will atempt to
* remain. Zero seconds means stay as caught up as possible.
*/
Seconds getSlaveDelay() const {
return _slaveDelay;
}
/**
* Returns true if this member may vote in elections.
*/
bool isVoter() const {
return _votes != 0;
}
/**
* Returns the number of votes that this member gets.
*/
int getNumVotes() const {
return isVoter() ? 1 : 0;
}
/**
* Returns true if this member is an arbiter (is not data-bearing).
*/
bool isArbiter() const {
return _arbiterOnly;
}
/**
* Returns true if this member is hidden (not reported by isMaster, not electable).
*/
bool isHidden() const {
return _hidden;
}
/**
* Returns true if this member should build secondary indexes.
*/
bool shouldBuildIndexes() const {
return _buildIndexes;
}
/**
* Gets the number of replica set tags, including internal '$' tags, for this member.
*/
size_t getNumTags() const {
return _tags.size();
}
/**
* Returns true if this MemberConfig has any non-internal tags, using "tagConfig" to
* determine the internal property of the tags.
*/
bool hasTags(const ReplSetTagConfig& tagConfig) const;
/**
* Gets a begin iterator over the tags for this member.
*/
TagIterator tagsBegin() const {
return _tags.begin();
}
/**
* Gets an end iterator over the tags for this member.
*/
TagIterator tagsEnd() const {
return _tags.end();
}
/**
* Returns true if this represents the configuration of an electable member.
*/
bool isElectable() const {
return !isArbiter() && getPriority() > 0;
}
/**
* Returns the member config as a BSONObj, using "tagConfig" to generate the tag subdoc.
*/
BSONObj toBSON(const ReplSetTagConfig& tagConfig) const;
private:
const HostAndPort& _host() const {
return getHostAndPort(SplitHorizon::kDefaultHorizon);
}
MemberId _id;
double _priority; // 0 means can never be primary
int _votes; // Can this member vote? Only 0 and 1 are valid. Default 1.
bool _arbiterOnly;
Seconds _slaveDelay;
bool _hidden; // if set, don't advertise to drivers in isMaster.
bool _buildIndexes; // if false, do not create any non-_id indexes
std::vector<ReplSetTag> _tags; // tagging for data center, rack, etc.
SplitHorizon _splitHorizon;
};
} // namespace repl
} // namespace mongo
|
