There is no such method. You will need to get all room IDs through getAllRooms(). Then you will need to iterate over each room Id and call getLiveRoomInfo() to get the name, properties, etc details about that room.
This is an intended behaviour because if there was such an API, that api would have resulted in huge amount of data transfer in result callbacks.
There is also an API called getRoomsWithProperty() which returns a list of rooms having a certain property that you would have passed as argument during calling.