Users loop in Meteor Js - mongodb

Question

For example I have 50 users and I have collection like
Rooms = new Mongo.Collection('rooms');
First I want to mix Users like if I have this [id1,id2,id3...] make it this [id52,id91241,id2...]
and after put in every Room 5 users like
for (i=0;i<countofmyusers;i=i+5)
crete new room and put 5 users // ?? how .. Rooms.insert(??)
{
users: [id1,id44,id2451,id921241,id23]
...
}
Any idea how to do it ?

Answer 1

Here's an example function that creates a set of rooms, each with a random sample of users:
var randomRooms = function(roomCount, sampleSize) {
// extract all of the user ids in the datbase
var userIds = _.pluck(Meteor.users.find({}, {fields: {_id: 1}}).fetch(), '_id');
// create roomCount rooms
_.times(roomCount, function() {
// insert a new room with a random sample of users of size sampleSize
Rooms.insert({users: _.sample(userIds, sampleSize)});
});
};
Here's a new version which enforces that user ids not be repeated across groups (i.e. each user will be assigned to one and only one group):
var randomRooms = function(userCountInEachRoom) {
// extract all of the user ids in the datbase
var userIds = _.pluck(Meteor.users.find({}, {fields: {_id: 1}}).fetch(), '_id');
// create a new array of randomly sorted user ids
var shuffledUserIds = _.shuffle(userIds);
// create a list of lists of user ids where each list has at most
// userCountInEachRoom ids - note that users will not be repeated in any lists
var userLists = [];
while (shuffledUserIds.length > 0)
userLists.push(shuffledUserIds.splice(0, userCountInEachRoom));
// insert a new group for each sub-array of user ids
_.each(userLists, function(users) {
Rooms.insert({users: users});
});
};
You'd call it like randomRooms(5) to place at most five users in each group. Note that the last group will have fewer than five users if the total user count is not a multiple of five.