virtual QList<BufferInfo> requestBuffers(UserId user, QDateTime since = QDateTime());
virtual bool removeBuffer(const UserId &user, const BufferId &bufferId);
virtual void setBufferLastSeen(UserId user, const BufferId &bufferId, const QDateTime &seenDate);
virtual QList<BufferInfo> requestBuffers(UserId user, QDateTime since = QDateTime());
virtual bool removeBuffer(const UserId &user, const BufferId &bufferId);
virtual void setBufferLastSeen(UserId user, const BufferId &bufferId, const QDateTime &seenDate);