const rooms = {}; function getOrCreateRoom(roomId) { let room = rooms[roomId]; if (!room) { room = { roomId: roomId, participants: [] }; rooms[roomId] = room; } return room; } function addParticipant(roomId, participantId, participantName) { let room = getOrCreateRoom(roomId); room.participants.push({ participantId, participantName, }); rooms[roomId] = room; } module.exports = {getOrCreateRoom, addParticipant}