function createRoom(){

};
function sendInvitation(){

};
function sendMessage(){

};
function chatRoomMessages(){

};
function index(){
    
};
function createRoom(){

};
function sendInvitation(){

};
function sendMessage(){

};
function chatRoomMessages(){

};
exports.index = index; 
exports.createRoom = createRoom;
exports.sendInvitation = sendInvitation;
exports.sendMessage = sendMessage;

Update chatroomsController.js