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
|
/**
* Copyright (C) 2008 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.
*/
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kReplication
#include "mongo/platform/basic.h"
#include "mongo/db/repl/sync.h"
#include <string>
#include "mongo/db/catalog/collection.h"
#include "mongo/db/catalog/database.h"
#include "mongo/db/client.h"
#include "mongo/db/jsobj.h"
#include "mongo/db/record_id.h"
#include "mongo/db/repl/oplogreader.h"
#include "mongo/util/assert_util.h"
#include "mongo/util/log.h"
namespace mongo {
using std::endl;
using std::string;
namespace repl {
void Sync::setHostname(const string& hostname) {
hn = hostname;
}
BSONObj Sync::getMissingDoc(OperationContext* txn, Database* db, const BSONObj& o) {
OplogReader missingObjReader; // why are we using OplogReader to run a non-oplog query?
const char *ns = o.getStringField("ns");
// capped collections
Collection* collection = db->getCollection(ns);
if ( collection && collection->isCapped() ) {
log() << "replication missing doc, but this is okay for a capped collection (" << ns << ")" << endl;
return BSONObj();
}
const int retryMax = 3;
for (int retryCount = 1; retryCount <= retryMax; ++retryCount) {
if (retryCount != 1) {
// if we are retrying, sleep a bit to let the network possibly recover
sleepsecs(retryCount * retryCount);
}
try {
bool ok = missingObjReader.connect(HostAndPort(hn));
if (!ok) {
warning() << "network problem detected while connecting to the "
<< "sync source, attempt " << retryCount << " of "
<< retryMax << endl;
continue; // try again
}
}
catch (const SocketException&) {
warning() << "network problem detected while connecting to the "
<< "sync source, attempt " << retryCount << " of "
<< retryMax << endl;
continue; // try again
}
// might be more than just _id in the update criteria
BSONObj query = BSONObjBuilder().append(o.getObjectField("o2")["_id"]).obj();
BSONObj missingObj;
try {
missingObj = missingObjReader.findOne(ns, query);
}
catch (const SocketException&) {
warning() << "network problem detected while fetching a missing document from the "
<< "sync source, attempt " << retryCount << " of "
<< retryMax << endl;
continue; // try again
}
catch (DBException& e) {
log() << "replication assertion fetching missing object: " << e.what() << endl;
throw;
}
// success!
return missingObj;
}
// retry count exceeded
msgasserted(15916,
str::stream() << "Can no longer connect to initial sync source: " << hn);
}
bool Sync::shouldRetry(OperationContext* txn, const BSONObj& o) {
const NamespaceString nss(o.getStringField("ns"));
// Take an X lock on the database in order to preclude other modifications. Also, the
// database might not exist yet, so create it.
AutoGetOrCreateDb autoDb(txn, nss.db(), MODE_X);
Database* const db = autoDb.getDb();
// we don't have the object yet, which is possible on initial sync. get it.
log() << "replication info adding missing object" << endl; // rare enough we can log
BSONObj missingObj = getMissingDoc(txn, db, o);
if( missingObj.isEmpty() ) {
log() << "replication missing object not found on source. presumably deleted later in oplog" << endl;
log() << "replication o2: " << o.getObjectField("o2").toString() << endl;
log() << "replication o firstfield: " << o.getObjectField("o").firstElementFieldName() << endl;
return false;
}
else {
WriteUnitOfWork wunit(txn);
Collection* const collection = db->getOrCreateCollection(txn, nss.toString());
invariant(collection);
StatusWith<RecordId> result = collection->insertDocument(txn, missingObj, true);
uassert(15917,
str::stream() << "failed to insert missing doc: " << result.toString(),
result.isOK() );
LOG(1) << "replication inserted missing doc: " << missingObj.toString() << endl;
wunit.commit();
return true;
}
}
} // namespace repl
} // namespace mongo
|
