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
|
// @file syncclusterconnection.h
/*
* Copyright 2010 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* 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 GNU Affero General 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 <boost/scoped_ptr.hpp>
#include "mongo/bson/bsonelement.h"
#include "mongo/bson/bsonobj.h"
#include "mongo/client/dbclientinterface.h"
#include "mongo/util/concurrency/mutex.h"
namespace mongo {
/**
* This is a connection to a cluster of servers that operate as one
* for super high durability.
*
* Write operations are two-phase. First, all nodes are asked to fsync. If successful
* everywhere, the write is sent everywhere and then followed by an fsync. There is no
* rollback if a problem occurs during the second phase. Naturally, with all these fsyncs,
* these operations will be quite slow -- use sparingly.
*
* Read operations are sent to a single random node.
*
* The class checks if a command is read or write style, and sends to a single
* node if a read lock command and to all in two phases with a write style command.
*/
class SyncClusterConnection : public DBClientBase {
public:
using DBClientBase::query;
using DBClientBase::update;
using DBClientBase::remove;
class QueryHandler;
/**
* @param commaSeparated should be 3 hosts comma separated
*/
SyncClusterConnection( const std::list<HostAndPort> &, double socketTimeout = 0);
SyncClusterConnection( std::string commaSeparated, double socketTimeout = 0);
SyncClusterConnection( const std::string& a,
const std::string& b,
const std::string& c,
double socketTimeout = 0 );
~SyncClusterConnection();
/**
* @return true if all servers are up and ready for writes
*/
bool prepare( std::string& errmsg );
// --- from DBClientInterface
virtual BSONObj findOne(const std::string &ns, const Query& query, const BSONObj *fieldsToReturn, int queryOptions);
virtual std::auto_ptr<DBClientCursor> query(const std::string &ns, Query query, int nToReturn, int nToSkip,
const BSONObj *fieldsToReturn, int queryOptions, int batchSize );
virtual std::auto_ptr<DBClientCursor> getMore( const std::string &ns, long long cursorId, int nToReturn, int options );
virtual void insert( const std::string &ns, BSONObj obj, int flags=0);
virtual void insert( const std::string &ns, const std::vector< BSONObj >& v, int flags=0);
virtual void remove( const std::string &ns , Query query, int flags );
virtual void update( const std::string &ns , Query query , BSONObj obj , int flags );
virtual bool call( Message &toSend, Message &response, bool assertOk , std::string * actualServer );
virtual void say( Message &toSend, bool isRetry = false , std::string * actualServer = 0 );
virtual void sayPiggyBack( Message &toSend );
virtual void killCursor( long long cursorID );
virtual std::string getServerAddress() const { return _address; }
virtual bool isFailed() const { return false; }
virtual bool isStillConnected();
virtual std::string toString() const { return _toString(); }
virtual BSONObj getLastErrorDetailed(const std::string& db,
bool fsync=false,
bool j=false,
int w=0,
int wtimeout=0);
virtual BSONObj getLastErrorDetailed(bool fsync=false, bool j=false, int w=0, int wtimeout=0);
virtual bool callRead( Message& toSend , Message& response );
virtual ConnectionString::ConnectionType type() const { return ConnectionString::SYNC; }
void setAllSoTimeouts( double socketTimeout );
double getSoTimeout() const { return _socketTimeout; }
virtual bool lazySupported() const { return false; }
// This override of runCommand intentionally calls findOne to construct a legacy
// OP_QUERY command. The reason for this is that delicate logic for targeting/locking
// config servers is in SyncClusterConnection::findOne, and refactoring that logic
// is both risky and of dubious value as we move to config server replica sets (CSRS).
virtual bool runCommand(const std::string& dbname,
const BSONObj& cmd,
BSONObj& info,
int options) final;
virtual void setRunCommandHook(DBClientWithCommands::RunCommandHookFunc func);
virtual void setPostRunCommandHook(DBClientWithCommands::PostRunCommandHookFunc func);
/**
* Allow custom query processing through an external (e.g. mongos-only) service.
*
* Takes ownership of attached handler.
*/
void attachQueryHandler( QueryHandler* handler );
protected:
virtual void _auth(const BSONObj& params);
private:
SyncClusterConnection( SyncClusterConnection& prev, double socketTimeout = 0 );
std::string _toString() const;
bool _commandOnActive(const std::string &dbname, const BSONObj& cmd, BSONObj &info, int options=0);
std::auto_ptr<DBClientCursor> _queryOnActive(const std::string &ns, Query query, int nToReturn, int nToSkip,
const BSONObj *fieldsToReturn, int queryOptions, int batchSize );
int _lockType( const std::string& name );
void _checkLast();
void _connect( const std::string& host );
std::string _address;
std::vector<std::string> _connAddresses;
std::vector<DBClientConnection*> _conns;
std::vector<BSONObj> _lastErrors;
// Optionally attached by user
boost::scoped_ptr<QueryHandler> _customQueryHandler;
mongo::mutex _mutex;
std::map<std::string,int> _lockTypes;
// End mutex
double _socketTimeout;
};
/**
* Interface for custom query processing for the SCC.
* Allows plugging different host query behaviors for different types of queries.
*/
class SyncClusterConnection::QueryHandler {
public:
virtual ~QueryHandler() {};
/**
* Returns true if the query can be processed using this handler.
*/
virtual bool canHandleQuery( const std::string& ns, Query query ) = 0;
/**
* Returns a cursor on one of the hosts with the desired results for the query.
* May throw or return an empty auto_ptr on failure.
*/
virtual std::auto_ptr<DBClientCursor> handleQuery( const std::vector<std::string>& hosts,
const std::string &ns,
Query query,
int nToReturn,
int nToSkip,
const BSONObj *fieldsToReturn,
int queryOptions,
int batchSize ) = 0;
};
class UpdateNotTheSame : public UserException {
public:
UpdateNotTheSame( int code , const std::string& msg , const std::vector<std::string>& addrs , const std::vector<BSONObj>& lastErrors )
: UserException( code , msg ) , _addrs( addrs ) , _lastErrors( lastErrors ) {
verify( _addrs.size() == _lastErrors.size() );
}
virtual ~UpdateNotTheSame() throw() {
}
unsigned size() const {
return _addrs.size();
}
std::pair<std::string,BSONObj> operator[](unsigned i) const {
return std::make_pair( _addrs[i] , _lastErrors[i] );
}
private:
std::vector<std::string> _addrs;
std::vector<BSONObj> _lastErrors;
};
};
|
