How to find text in json array - node.js

Question

Im making a game and one of its functions is to join/create private rooms. Private rooms are generated randomly, but before generating a room, I want to try to be sure that the room id don't exists.
var rooms = {
'ROOM ID GENERATED RANDOMLY':
Room {
id: 'ROOM ID GENERATED RANDOMLY',
players: [],
gameState: 'WAITING',
currentCard: 'g:2',
currentPlayerIndex: NaN,
currentDirection: 1,
cardsStack: [] },
'ROOM ID GENERATED RANDOMLY':
Room {
id: 'ROOM ID GENERATED RANDOMLY',
players: [ [Player] ],
gameState: 'WAITING',
currentCard: 'g:2',
currentPlayerIndex: 0,
currentDirection: 1,
cardsStack: [] },
...
}
Already tried
var SEARCH = 'x';
for (var i=0; i < rooms.length; i++) {
console.log(rooms[i])
if (rooms[i].Room.id === SEARCH) {
return rooms[i];
}
}

Answer 1

Try this function
function roomIdIsUnique (newKey) {
var roomKeys = Object.keys(rooms);
for (const key of roomKeys) {
if (key === newKey) return false;
}
return true;
}
var rooms = { /* Room objects */ }
var newRoomKey = /* Generate new room key code */
if (roomIdIsUnique(newRoomKey)) {
/* Continue */
} else {
/* Do something else */
}

Answer 2

This question is pretty vague, but I'll do my best to answer it.
You can use Object.keys() to get an array containing the keys, and then run the Array#indexOf function on that array. It will return -1 if the key is not in the array, else it will return the index
var rooms = { "key1": { property: "123" }, "key2": { property: "abc" } }
if(Object.keys(rooms).indexOf(SEARCH) != -1) {
alert("Room id exists");
} else {
alert("Room does not exist");
}