ScopedCollectionMetadata MetadataManager::getActiveMetadata() {
stdx::lock_guard<stdx::mutex> scopedLock(_managerLock);
if (!_activeMetadataTracker) {
return ScopedCollectionMetadata();
}
return ScopedCollectionMetadata(this, _activeMetadataTracker.get());
}
boost::optional<ScopedCollectionMetadata> MetadataManager::getActiveMetadata(
std::shared_ptr<MetadataManager> self, const boost::optional<LogicalTime>& atClusterTime) {
stdx::lock_guard<stdx::mutex> lg(_managerLock);
if (_metadata.empty()) {
return boost::none;
}
auto activeMetadataTracker = _metadata.back();
const auto& activeMetadata = activeMetadataTracker->metadata;
// We don't keep routing history for unsharded collections, so if the collection is unsharded
// just return the active metadata
if (!atClusterTime || !activeMetadata.isSharded()) {
return ScopedCollectionMetadata(std::make_shared<RangePreserver>(
lg, std::move(self), std::move(activeMetadataTracker)));
}
auto chunkManager = activeMetadata.getChunkManager();
auto chunkManagerAtClusterTime = std::make_shared<ChunkManager>(
chunkManager->getRoutingHistory(), atClusterTime->asTimestamp());
class MetadataAtTimestamp : public ScopedCollectionMetadata::Impl {
public:
MetadataAtTimestamp(CollectionMetadata metadata) : _metadata(std::move(metadata)) {}
const CollectionMetadata& get() override {
return _metadata;
}
private:
CollectionMetadata _metadata;
};
return ScopedCollectionMetadata(std::make_shared<MetadataAtTimestamp>(
CollectionMetadata(chunkManagerAtClusterTime, activeMetadata.shardId())));
}