Status _findAllCollections(const ConnectionString& configLoc,
bool optionalEpochs,
OwnedPointerMap<string, CollectionType>* collections)
{
scoped_ptr<ScopedDbConnection> connPtr;
try {
connPtr.reset(ScopedDbConnection::getInternalScopedDbConnection(configLoc, 30));
ScopedDbConnection& conn = *connPtr;
scoped_ptr<DBClientCursor> cursor(_safeCursor(conn->query(CollectionType::ConfigNS,
Query())));
while (cursor->more()) {
BSONObj collDoc = cursor->nextSafe();
CollectionType* coll = new CollectionType();
string errMsg;
coll->parseBSON(collDoc, &errMsg);
// Needed for the v3 to v4 upgrade
bool epochNotSet = !coll->isEpochSet() || !coll->getEpoch().isSet();
if (optionalEpochs && epochNotSet) {
// Set our epoch to something here, just to allow
coll->setEpoch(OID::gen());
}
if (errMsg != "" || !coll->isValid(&errMsg)) {
return Status(ErrorCodes::UnsupportedFormat,
stream() << "invalid collection " << collDoc
<< " read from the config server" << causedBy(errMsg));
}
if (coll->isDroppedSet() && coll->getDropped()) {
continue;
}
if (optionalEpochs && epochNotSet) {
coll->setEpoch(OID());
}
collections->mutableMap().insert(make_pair(coll->getNS(), coll));
}
}
catch (const DBException& e) {
return e.toStatus();
}
connPtr->done();
return Status::OK();
}
/**
* Stores ranges for a particular collection and shard starting from some version
*/
void storeCollectionRanges( const NamespaceString& nss,
const string& shardName,
const vector<KeyRange>& ranges,
const ChunkVersion& startVersion ) {
// Get key pattern from first range
ASSERT_GREATER_THAN( ranges.size(), 0u );
CollectionType coll;
coll.setNS( nss.ns() );
coll.setKeyPattern( ranges.begin()->keyPattern );
coll.setEpoch( startVersion.epoch() );
coll.setUpdatedAt( 1ULL );
string errMsg;
ASSERT( coll.isValid( &errMsg ) );
DBDirectClient client(&_txn);
client.update( CollectionType::ConfigNS,
BSON( CollectionType::ns( coll.getNS() ) ),
coll.toBSON(), true, false );
ChunkVersion nextVersion = startVersion;
for ( vector<KeyRange>::const_iterator it = ranges.begin(); it != ranges.end(); ++it ) {
ChunkType chunk;
// TODO: We should not rely on the serialized ns, minkey being unique in the future,
// causes problems since it links string serialization to correctness.
chunk.setName( Chunk::genID( nss, it->minKey ) );
chunk.setShard( shardName );
chunk.setNS( nss.ns() );
chunk.setVersion( nextVersion );
chunk.setMin( it->minKey );
chunk.setMax( it->maxKey );
nextVersion.incMajor();
client.insert( ChunkType::ConfigNS, chunk.toBSON() );
}
}
Status MetadataLoader::initCollection( const string& ns,
const string& shard,
CollectionMetadata* metadata )
{
//
// Bring collection entry from the config server.
//
BSONObj collObj;
{
try {
ScopedDbConnection conn( _configLoc.toString(), 30 );
collObj = conn->findOne( CollectionType::ConfigNS, QUERY(CollectionType::ns()<<ns));
conn.done();
}
catch ( const DBException& e ) {
string errMsg = str::stream() << "could not query collection metadata"
<< causedBy( e );
// We deliberately do not return conn to the pool, since it was involved
// with the error here.
return Status( ErrorCodes::HostUnreachable, errMsg );
}
}
CollectionType collDoc;
string errMsg;
if ( !collDoc.parseBSON( collObj, &errMsg ) || !collDoc.isValid( &errMsg ) ) {
return Status( ErrorCodes::FailedToParse, errMsg );
}
//
// Load or generate default chunks for collection config.
//
if ( collDoc.isKeyPatternSet() && !collDoc.getKeyPattern().isEmpty() ) {
metadata->_keyPattern = collDoc.getKeyPattern();
metadata->_shardVersion = ChunkVersion( 0, 0, collDoc.getEpoch() );
metadata->_collVersion = ChunkVersion( 0, 0, collDoc.getEpoch() );
return Status::OK();
}
else if ( collDoc.isPrimarySet() && collDoc.getPrimary() == shard ) {
if ( shard == "" ) {
warning() << "shard not verified, assuming collection " << ns
<< " is unsharded on this shard" << endl;
}
metadata->_keyPattern = BSONObj();
metadata->_shardVersion = ChunkVersion( 1, 0, collDoc.getEpoch() );
metadata->_collVersion = metadata->_shardVersion;
return Status::OK();
}
else {
errMsg = str::stream() << "collection " << ns << " does not have a shard key "
<< "and primary " << ( collDoc.isPrimarySet() ? collDoc.getPrimary() : "" )
<< " does not match this shard " << shard;
return Status( ErrorCodes::RemoteChangeDetected, errMsg );
}
}
bool MetadataLoader::initCollection(const string& ns,
const string& shard,
const CollectionManager* oldManager,
CollectionManager* manager,
string* errMsg) {
//
// Bring collection entry from the config server.
//
BSONObj collObj;
{
scoped_ptr<ScopedDbConnection> connPtr;
try {
connPtr.reset(
ScopedDbConnection::getInternalScopedDbConnection(_configLoc.toString(), 30));
ScopedDbConnection& conn = *connPtr;
collObj = conn->findOne(CollectionType::ConfigNS, QUERY(CollectionType::ns()<<ns));
}
catch (const DBException& e) {
*errMsg = str::stream() << "caught exception accessing the config servers "
<< causedBy(e);
// We deliberately do not return connPtr to the pool, since it was involved
// with the error here.
return false;
}
connPtr->done();
}
CollectionType collDoc;
if (!collDoc.parseBSON(collObj, errMsg) || !collDoc.isValid(errMsg)) {
return false;
}
//
// Load or generate default chunks for collection config.
//
if (!collDoc.getKeyPattern().isEmpty()) {
manager->_key = collDoc.getKeyPattern();
if(!initChunks(collDoc, ns, shard, oldManager, manager, errMsg)){
return false;
}
}
else if(collDoc.getPrimary() == shard) {
if (shard == "") {
warning() << "shard not verified, assuming collection "
<< ns << " is unsharded on this shard" << endl;
}
manager->_key = BSONObj();
manager->_maxShardVersion = ChunkVersion(1, 0, collDoc.getEpoch());
manager->_maxCollVersion = manager->_maxShardVersion;
}
else {
*errMsg = str::stream() << "collection " << ns << " does not have a shard key "
<< "and primary " << collDoc.getPrimary()
<< " does not match this shard " << shard;
return false;
}
return true;
}
Status MetadataLoader::initCollection( const string& ns,
const string& shard,
CollectionMetadata* metadata ) const
{
//
// Bring collection entry from the config server.
//
BSONObj collDoc;
{
try {
ScopedDbConnection conn( _configLoc.toString(), 30 );
collDoc = conn->findOne( CollectionType::ConfigNS, QUERY(CollectionType::ns()<<ns));
conn.done();
}
catch ( const DBException& e ) {
string errMsg = str::stream() << "could not query collection metadata"
<< causedBy( e );
// We deliberately do not return conn to the pool, since it was involved
// with the error here.
return Status( ErrorCodes::HostUnreachable, errMsg );
}
}
string errMsg;
if ( collDoc.isEmpty() ) {
errMsg = str::stream() << "could not load metadata, collection " << ns << " not found";
warning() << errMsg << endl;
return Status( ErrorCodes::NamespaceNotFound, errMsg );
}
CollectionType collInfo;
if ( !collInfo.parseBSON( collDoc, &errMsg ) || !collInfo.isValid( &errMsg ) ) {
errMsg = str::stream() << "could not parse metadata for collection " << ns
<< causedBy( errMsg );
warning() << errMsg << endl;
return Status( ErrorCodes::FailedToParse, errMsg );
}
if ( collInfo.isDroppedSet() && collInfo.getDropped() ) {
errMsg = str::stream() << "could not load metadata, collection " << ns
<< " was dropped";
warning() << errMsg << endl;
return Status( ErrorCodes::NamespaceNotFound, errMsg );
}
if ( collInfo.isKeyPatternSet() && !collInfo.getKeyPattern().isEmpty() ) {
// Sharded collection, need to load chunks
metadata->_keyPattern = collInfo.getKeyPattern();
metadata->_shardVersion = ChunkVersion( 0, 0, collInfo.getEpoch() );
metadata->_collVersion = ChunkVersion( 0, 0, collInfo.getEpoch() );
return Status::OK();
}
else if ( collInfo.isPrimarySet() && collInfo.getPrimary() == shard ) {
// A collection with a non-default primary
// Empty primary field not allowed if set
dassert( collInfo.getPrimary() != "" );
metadata->_keyPattern = BSONObj();
metadata->_shardVersion = ChunkVersion( 1, 0, collInfo.getEpoch() );
metadata->_collVersion = metadata->_shardVersion;
return Status::OK();
}
else {
// A collection with a primary that doesn't match this shard or is empty, the primary
// may have changed before we loaded.
errMsg = // br
str::stream() << "collection " << ns << " does not have a shard key "
<< "and primary "
<< ( collInfo.isPrimarySet() ? collInfo.getPrimary() : "" )
<< " does not match this shard " << shard;
warning() << errMsg << endl;
metadata->_collVersion = ChunkVersion( 0, 0, OID() );
return Status( ErrorCodes::RemoteChangeDetected, errMsg );
}
}