auto_ptr<DBClientCursor> DBClientReplicaSet::query(const string &ns, Query query, int nToReturn, int nToSkip,
const BSONObj *fieldsToReturn, int queryOptions, int batchSize) {
if ( queryOptions & QueryOption_SlaveOk ) {
// we're ok sending to a slave
// we'll try 2 slaves before just using master
// checkSlave will try a different slave automatically after a failure
for ( int i=0; i<3; i++ ) {
try {
return checkSlaveQueryResult( checkSlave()->query(ns,query,nToReturn,nToSkip,fieldsToReturn,queryOptions,batchSize) );
}
catch ( DBException &e ) {
LOG(1) << "can't query replica set slave " << i << " : " << _slaveHost << causedBy( e ) << endl;
}
}
}
return checkMaster()->query(ns,query,nToReturn,nToSkip,fieldsToReturn,queryOptions,batchSize);
}
auto_ptr<DBClientCursor> DBClientReplicaSet::query(const string &ns,
Query query,
int nToReturn,
int nToSkip,
const BSONObj *fieldsToReturn,
int queryOptions,
int batchSize) {
shared_ptr<ReadPreferenceSetting> readPref( _extractReadPref( query.obj, queryOptions ) );
if ( _isSecondaryQuery( ns, query.obj, *readPref ) ) {
LOG( 3 ) << "dbclient_rs query using secondary or tagged node selection in "
<< _getMonitor()->getName() << ", read pref is "
<< readPref->toBSON() << " (primary : "
<< ( _master.get() != NULL ?
_master->getServerAddress() : "[not cached]" )
<< ", lastTagged : "
<< ( _lastSlaveOkConn.get() != NULL ?
_lastSlaveOkConn->getServerAddress() : "[not cached]" )
<< ")" << endl;
string lastNodeErrMsg;
for (size_t retry = 0; retry < MAX_RETRY; retry++) {
try {
DBClientConnection* conn = selectNodeUsingTags(readPref);
if (conn == NULL) {
break;
}
auto_ptr<DBClientCursor> cursor = conn->query(ns, query,
nToReturn, nToSkip, fieldsToReturn, queryOptions,
batchSize);
return checkSlaveQueryResult(cursor);
}
catch (const DBException &dbExcep) {
StringBuilder errMsgBuilder;
errMsgBuilder << "can't query replica set node "
<< _lastSlaveOkHost.toString() << ": " << causedBy( dbExcep );
lastNodeErrMsg = errMsgBuilder.str();
LOG(1) << lastNodeErrMsg << endl;
invalidateLastSlaveOkCache();
}
}
StringBuilder assertMsg;
assertMsg << "Failed to do query, no good nodes in " << _getMonitor()->getName();
if ( !lastNodeErrMsg.empty() ) {
assertMsg << ", last error: " << lastNodeErrMsg;
}
uasserted( 16370, assertMsg.str() );
}
LOG( 3 ) << "dbclient_rs query to primary node in " << _getMonitor()->getName() << endl;
return checkMaster()->query(ns, query, nToReturn, nToSkip, fieldsToReturn,
queryOptions, batchSize);
}
