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
|
/**
* Copyright (C) 2016 MongoDB 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 <string>
#include "mongo/s/client/shard.h"
#include "mongo/base/disallow_copying.h"
#include "mongo/executor/task_executor.h"
#include "mongo/stdx/mutex.h"
namespace mongo {
/*
* Maintains the targeting and command execution logic for a single shard. Performs polling of
* the shard (if replica set).
*/
class ShardRemote : public Shard {
MONGO_DISALLOW_COPYING(ShardRemote);
public:
/**
* Instantiates a new shard connection management object for the specified shard.
*/
ShardRemote(const ShardId& id,
const ConnectionString& originalConnString,
std::unique_ptr<RemoteCommandTargeter> targeter);
~ShardRemote();
const ConnectionString getConnString() const override;
const ConnectionString originalConnString() const override {
return _originalConnString;
}
std::shared_ptr<RemoteCommandTargeter> getTargeter() const override {
return _targeter;
}
void updateReplSetMonitor(const HostAndPort& remoteHost,
const Status& remoteCommandStatus) override;
std::string toString() const override;
bool isRetriableError(ErrorCodes::Error code, RetryPolicy options) final;
Status createIndexOnConfig(OperationContext* opCtx,
const NamespaceString& ns,
const BSONObj& keys,
bool unique) override;
void updateLastCommittedOpTime(LogicalTime lastCommittedOpTime) final;
LogicalTime getLastCommittedOpTime() const final;
void runFireAndForgetCommand(OperationContext* opCtx,
const ReadPreferenceSetting& readPref,
const std::string& dbName,
const BSONObj& cmdObj) final;
private:
struct AsyncCmdHandle {
HostAndPort hostTargetted;
executor::TaskExecutor::CallbackHandle handle;
};
/**
* Returns the metadata that should be used when running commands against this shard with
* the given read preference.
*/
BSONObj _appendMetadataForCommand(OperationContext* opCtx,
const ReadPreferenceSetting& readPref);
StatusWith<Shard::CommandResponse> _runCommand(OperationContext* opCtx,
const ReadPreferenceSetting& readPref,
const std::string& dbname,
Milliseconds maxTimeMSOverride,
const BSONObj& cmdObj) final;
StatusWith<Shard::QueryResponse> _runExhaustiveCursorCommand(
OperationContext* opCtx,
const ReadPreferenceSetting& readPref,
const std::string& dbName,
Milliseconds maxTimeMSOverride,
const BSONObj& cmdObj) final;
StatusWith<QueryResponse> _exhaustiveFindOnConfig(
OperationContext* opCtx,
const ReadPreferenceSetting& readPref,
const repl::ReadConcernLevel& readConcernLevel,
const NamespaceString& nss,
const BSONObj& query,
const BSONObj& sort,
boost::optional<long long> limit) final;
StatusWith<AsyncCmdHandle> _scheduleCommand(
OperationContext* opCtx,
const ReadPreferenceSetting& readPref,
const std::string& dbName,
Milliseconds maxTimeMSOverride,
const BSONObj& cmdObj,
const executor::TaskExecutor::RemoteCommandCallbackFn& cb);
/**
* Protects _lastCommittedOpTime.
*/
mutable stdx::mutex _lastCommittedOpTimeMutex;
/**
* Logical time representing the latest opTime timestamp known to be in this shard's majority
* committed snapshot. Only the latest time is kept because lagged secondaries may return earlier
* times.
*/
LogicalTime _lastCommittedOpTime;
/**
* Connection string for the shard at the creation time.
*/
const ConnectionString _originalConnString;
/**
* Targeter for obtaining hosts from which to read or to which to write.
*/
const std::shared_ptr<RemoteCommandTargeter> _targeter;
};
} // namespace mongo
|
