void DBClientCursor::dataReceived(bool& retry, string& host) {
// If this is a reply to our initial command request.
if (_isCommand && cursorId == 0) {
commandDataReceived();
return;
}
QueryResult::View qr = batch.m.singleData().view2ptr();
resultFlags = qr.getResultFlags();
if (qr.getResultFlags() & ResultFlag_ErrSet) {
wasError = true;
}
if (qr.getResultFlags() & ResultFlag_CursorNotFound) {
// cursor id no longer valid at the server.
invariant(qr.getCursorId() == 0);
if (!(opts & QueryOption_CursorTailable)) {
uasserted(13127,
str::stream() << "cursor id " << cursorId << " didn't exist on server.");
}
// 0 indicates no longer valid (dead)
cursorId = 0;
}
if (cursorId == 0 || !(opts & QueryOption_CursorTailable)) {
// only set initially: we don't want to kill it on end of data
// if it's a tailable cursor
cursorId = qr.getCursorId();
}
batch.nReturned = qr.getNReturned();
batch.pos = 0;
batch.data = qr.data();
batch.remainingBytes = qr.dataLen();
_client->checkResponse(batch.data, batch.nReturned, &retry, &host); // watches for "not master"
if (qr.getResultFlags() & ResultFlag_ShardConfigStale) {
BSONObj error;
verify(peekError(&error));
throw RecvStaleConfigException(
(string) "stale config on lazy receive" + causedBy(getErrField(error)), error);
}
/* this assert would fire the way we currently work:
verify( nReturned || cursorId == 0 );
*/
}
LegacyReply::LegacyReply(const Message* message) : _message(std::move(message)) {
invariant(message->operation() == opReply);
QueryResult::View qr = _message->singleData().view2ptr();
// should be checked by caller.
invariant(qr.msgdata().getNetworkOp() == opReply);
uassert(ErrorCodes::BadValue,
str::stream() << "Got legacy command reply with a bad cursorId field,"
<< " expected a value of 0 but got " << qr.getCursorId(),
qr.getCursorId() == 0);
uassert(ErrorCodes::BadValue,
str::stream() << "Got legacy command reply with a bad nReturned field,"
<< " expected a value of 1 but got " << qr.getNReturned(),
qr.getNReturned() == 1);
uassert(ErrorCodes::BadValue,
str::stream() << "Got legacy command reply with a bad startingFrom field,"
<< " expected a value of 0 but got " << qr.getStartingFrom(),
qr.getStartingFrom() == 0);
std::tie(_commandReply, _metadata) =
uassertStatusOK(rpc::upconvertReplyMetadata(BSONObj(qr.data())));
// Copy the bson array of documents from the message into
// a contiguous area of memory owned by _docBuffer so
// DocumentRange can be used to iterate over documents
auto cursorElem = _commandReply[LegacyReplyBuilder::kCursorTag];
if (cursorElem.eoo())
return;
BSONObj cursorObj = cursorElem.Obj();
auto firstBatchElem = cursorObj[LegacyReplyBuilder::kFirstBatchTag];
if (firstBatchElem.eoo())
return;
for (BSONObjIterator it(firstBatchElem.Obj()); it.more(); it.next()) {
invariant((*it).isABSONObj());
BSONObj doc = (*it).Obj();
doc.appendSelfToBufBuilder(_docBuffer);
}
const char* dataBegin = _docBuffer.buf();
const char* dataEnd = dataBegin + _docBuffer.len();
_outputDocs = DocumentRange(dataBegin, dataEnd);
return;
}
LegacyReply::LegacyReply(const Message* message) {
invariant(message->operation() == opReply);
QueryResult::View qr = message->singleData().view2ptr();
// should be checked by caller.
invariant(qr.msgdata().getNetworkOp() == opReply);
uassert(ErrorCodes::BadValue,
str::stream() << "Got legacy command reply with a bad cursorId field,"
<< " expected a value of 0 but got "
<< qr.getCursorId(),
qr.getCursorId() == 0);
uassert(ErrorCodes::BadValue,
str::stream() << "Got legacy command reply with a bad nReturned field,"
<< " expected a value of 1 but got "
<< qr.getNReturned(),
qr.getNReturned() == 1);
uassert(ErrorCodes::BadValue,
str::stream() << "Got legacy command reply with a bad startingFrom field,"
<< " expected a value of 0 but got "
<< qr.getStartingFrom(),
qr.getStartingFrom() == 0);
auto status = Validator<BSONObj>::validateLoad(qr.data(), qr.dataLen());
uassert(ErrorCodes::InvalidBSON,
str::stream() << "Got legacy command reply with invalid BSON in the metadata field"
<< causedBy(status),
status.isOK());
_commandReply = BSONObj(qr.data());
_commandReply.shareOwnershipWith(message->sharedBuffer());
if (_commandReply.firstElementFieldName() == "$err"_sd) {
// Upconvert legacy errors.
BSONObjBuilder bob;
bob.appendAs(_commandReply.firstElement(), "errmsg");
bob.append("ok", 0.0);
if (auto code = _commandReply["code"]) {
bob.append(code);
}
_commandReply = bob.obj();
}
return;
}
void DBClientCursor::dataReceived( bool& retry, string& host ) {
QueryResult::View qr = batch.m->singleData().view2ptr();
resultFlags = qr.getResultFlags();
if ( qr.getResultFlags() & ResultFlag_ErrSet ) {
wasError = true;
}
if ( qr.getResultFlags() & ResultFlag_CursorNotFound ) {
// cursor id no longer valid at the server.
verify( qr.getCursorId() == 0 );
cursorId = 0; // 0 indicates no longer valid (dead)
if ( ! ( opts & QueryOption_CursorTailable ) )
throw UserException( 13127 , "getMore: cursor didn't exist on server, possible restart or timeout?" );
}
if ( cursorId == 0 || ! ( opts & QueryOption_CursorTailable ) ) {
// only set initially: we don't want to kill it on end of data
// if it's a tailable cursor
cursorId = qr.getCursorId();
}
batch.nReturned = qr.getNReturned();
batch.pos = 0;
batch.data = qr.data();
_client->checkResponse( batch.data, batch.nReturned, &retry, &host ); // watches for "not master"
if( qr.getResultFlags() & ResultFlag_ShardConfigStale ) {
BSONObj error;
verify( peekError( &error ) );
throw RecvStaleConfigException( (string)"stale config on lazy receive" + causedBy( getErrField( error ) ), error );
}
/* this assert would fire the way we currently work:
verify( nReturned || cursorId == 0 );
*/
}
virtual void process(Message& m, AbstractMessagingPort* port) {
while (true) {
if (inShutdown()) {
log() << "got request after shutdown()" << endl;
break;
}
DbResponse dbresponse;
{
auto opCtx = getGlobalServiceContext()->makeOperationContext(&cc());
assembleResponse(opCtx.get(), m, dbresponse, port->remote());
// opCtx must go out of scope here so that the operation cannot show up in currentOp
// results after the response reaches the client
}
if (!dbresponse.response.empty()) {
port->reply(m, dbresponse.response, dbresponse.responseTo);
if (dbresponse.exhaustNS.size() > 0) {
MsgData::View header = dbresponse.response.header();
QueryResult::View qr = header.view2ptr();
long long cursorid = qr.getCursorId();
if (cursorid) {
verify(dbresponse.exhaustNS.size() && dbresponse.exhaustNS[0]);
string ns = dbresponse.exhaustNS; // before reset() free's it...
m.reset();
BufBuilder b(512);
b.appendNum((int)0 /*size set later in appendData()*/);
b.appendNum(header.getId());
b.appendNum(header.getResponseTo());
b.appendNum((int)dbGetMore);
b.appendNum((int)0);
b.appendStr(ns);
b.appendNum((int)0); // ntoreturn
b.appendNum(cursorid);
m.appendData(b.buf(), b.len());
b.decouple();
DEV log() << "exhaust=true sending more";
continue; // this goes back to top loop
}
}
}
break;
}
}
virtual void process( Message& m , AbstractMessagingPort* port , LastError * le) {
OperationContextImpl txn;
while ( true ) {
if ( inShutdown() ) {
log() << "got request after shutdown()" << endl;
break;
}
lastError.startRequest( m , le );
DbResponse dbresponse;
assembleResponse(&txn, m, dbresponse, port->remote());
if ( dbresponse.response ) {
port->reply(m, *dbresponse.response, dbresponse.responseTo);
if( dbresponse.exhaustNS.size() > 0 ) {
MsgData::View header = dbresponse.response->header();
QueryResult::View qr = header.view2ptr();
long long cursorid = qr.getCursorId();
if( cursorid ) {
verify( dbresponse.exhaustNS.size() && dbresponse.exhaustNS[0] );
string ns = dbresponse.exhaustNS; // before reset() free's it...
m.reset();
BufBuilder b(512);
b.appendNum((int) 0 /*size set later in appendData()*/);
b.appendNum(header.getId());
b.appendNum(header.getResponseTo());
b.appendNum((int) dbGetMore);
b.appendNum((int) 0);
b.appendStr(ns);
b.appendNum((int) 0); // ntoreturn
b.appendNum(cursorid);
m.appendData(b.buf(), b.len());
b.decouple();
DEV log() << "exhaust=true sending more" << endl;
continue; // this goes back to top loop
}
}
}
break;
}
}
void operator()() const {
DBClientConnection dest;
string errmsg;
Timer connectTimer;
while (!dest.connect(HostAndPort(mongoBridgeGlobalParams.destUri), errmsg)) {
// If we can't connect for the configured timeout, give up
//
if (connectTimer.seconds() >= mongoBridgeGlobalParams.connectTimeoutSec) {
cout << "Unable to establish connection from " << mp_.psock->remoteString()
<< " to " << mongoBridgeGlobalParams.destUri
<< " after " << connectTimer.seconds() << " seconds. Giving up." << endl;
mp_.shutdown();
return;
}
sleepmillis(500);
}
Message m;
while( 1 ) {
try {
m.reset();
if ( !mp_.recv( m ) ) {
cout << "end connection " << mp_.psock->remoteString() << endl;
mp_.shutdown();
break;
}
sleepmillis(mongoBridgeGlobalParams.delay);
int oldId = m.header().getId();
if ( m.operation() == dbQuery || m.operation() == dbMsg || m.operation() == dbGetMore ) {
bool exhaust = false;
if ( m.operation() == dbQuery ) {
DbMessage d( m );
QueryMessage q( d );
exhaust = q.queryOptions & QueryOption_Exhaust;
}
Message response;
dest.port().call( m, response );
// nothing to reply with?
if ( response.empty() ) cleanup(0);
mp_.reply( m, response, oldId );
while ( exhaust ) {
MsgData::View header = response.header();
QueryResult::View qr = header.view2ptr();
if ( qr.getCursorId() ) {
response.reset();
dest.port().recv( response );
mp_.reply( m, response ); // m argument is ignored anyway
}
else {
exhaust = false;
}
}
}
else {
dest.port().say( m, oldId );
}
}
catch ( ... ) {
log() << "caught exception in Forwarder, continuing" << endl;
}
}
}