QList<Message> requestMsgs(UserId user, BufferId bufferId, MsgId first = -1, MsgId last = -1, int limit = -1) override;
QList<Message> requestAllMsgs(UserId user, MsgId first = -1, MsgId last = -1, int limit = -1) override;
QList<Message> requestMsgs(UserId user, BufferId bufferId, MsgId first = -1, MsgId last = -1, int limit = -1) override;
QList<Message> requestAllMsgs(UserId user, MsgId first = -1, MsgId last = -1, int limit = -1) override;