/**
 * Format:
 * logicalTime: {
 *     clusterTime: <highest known valid LogicalTime_MEM>
 * }
 */
class LogicalTimeMetadata {
public:
    explicit LogicalTimeMetadata(SignedLogicalTime time);

    static StatusWith<LogicalTimeMetadata> readFromMetadata(const BSONElement& metadataElem);
    void writeToMetadata(BSONObjBuilder* metadataBuilder) const;

    SignedLogicalTime getTime();

private:
    SignedLogicalTime _clusterTime;
};